GS2K Module Power Measurement Application Note NT11603A Rev

Transcription

1 GS2K Module Power Measurement Application Note 80560NT11603A Rev

2 SPECIFICATIONS ARE SUBJECT TO CHANGE WITHOUT NOTICE NOTICE While reasonable efforts have been made to assure the accuracy of this document, Telit assumes no liability resulting from any inaccuracies or omissions in this document, or from use of the information obtained herein. The information in this document has been carefully checked and is believed to be reliable. However, no responsibility is assumed for inaccuracies or omissions. Telit reserves the right to make changes to any products described herein and reserves the right to revise this document and to make changes from time to time in content hereof with no obligation to notify any person of revisions or changes. Telit does not assume any liability arising out of the application or use of any product, software, or circuit described herein; neither does it convey license under its patent rights or the rights of others. It is possible that this publication may contain references to, or information about Telit products (machines and programs), programming, or services that are not announced in your country. Such references or information must not be construed to mean that Telit intends to announce such Telit products, programming, or services in your country. COPYRIGHTS This instruction manual and the Telit products described in this instruction manual may be, include or describe copyrighted Telit material, such as computer programs stored in semiconductor memories or other media. Laws in the Italy and other countries preserve for Telit and its licensors certain exclusive rights for copyrighted material, including the exclusive right to copy, reproduce in any form, distribute and make derivative works of the copyrighted material. Accordingly, any copyrighted material of Telit and its licensors contained herein or in the Telit products described in this instruction manual may not be copied, reproduced, distributed, merged or modified in any manner without the express written permission of Telit. Furthermore, the purchase of Telit products shall not be deemed to grant either directly or by implication, estoppel, or otherwise, any license under the copyrights, patents or patent applications of Telit, as arises by operation of law in the sale of a product. COMPUTER SOFTWARE COPYRIGHTS The Telit and 3rd Party supplied Software (SW) products described in this instruction manual may include copyrighted Telit and other 3rd Party supplied computer programs stored in semiconductor memories or other media. Laws in the Italy and other countries preserve for Telit and other 3rd Party supplied SW certain exclusive rights for copyrighted computer programs, including the exclusive right to copy or reproduce in any form the copyrighted computer program. Accordingly, any copyrighted Telit or other 3rd Party supplied SW computer programs contained in the Telit products described in this instruction manual may not be copied (reverse engineered) or reproduced in any manner without the express written permission of Telit or the 3rd Party SW supplier. Furthermore, the purchase of Telit products shall not be deemed to grant either directly or by implication, estoppel, or otherwise, any license under the copyrights, patents or patent applications of Telit or other 3rd Party supplied SW, except for the normal non-exclusive, royalty free license to use that arises by operation of law in the sale of a product NT11603A Rev. 1.1 Page 2 of

3 USAGE AND DISCLOSURE RESTRICTIONS I. License Agreements The software described in this document is the property of Telit and its licensors. It is furnished by express license agreement only and may be used only in accordance with the terms of such an agreement. II. III. Copyrighted Materials Software and documentation are copyrighted materials. Making unauthorized copies is prohibited by law. No part of the software or documentation may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language or computer language, in any form or by any means, without prior written permission of Telit IV. High Risk Materials Components, units, or third-party products used in the product described herein are NOT fault-tolerant and are NOT designed, manufactured, or intended for use as on-line control equipment in the following hazardous environments requiring fail-safe controls: the operation of Nuclear Facilities, Aircraft Navigation or Aircraft Communication Systems, Air Traffic Control, Life Support, or Weapons Systems (High Risk Activities"). Telit and its supplier(s) specifically disclaim any expressed or implied warranty of fitness for such High Risk Activities. Trademarks TELIT and the Stylized T Logo are registered in Trademark Office. All other product or service names are the property of their respective owners. V. Third Party Rights The software may include Third Party Right software. In this case you agree to comply with all terms and conditions imposed on you in respect of such separate software. In addition to Third Party Terms, the disclaimer of warranty and limitation of liability provisions in this License shall apply to the Third Party Right software. TELIT HEREBY DISCLAIMS ANY AND ALL WARRANTIES EXPRESS OR IMPLIED FROM ANY THIRD PARTIES REGARDING ANY SEPARATE FILES, ANY THIRD PARTY MATERIALS INCLUDED IN THE SOFTWARE, ANY THIRD PARTY MATERIALS FROM WHICH THE SOFTWARE IS DERIVED (COLLECTIVELY OTHER CODE ), AND THE USE OF ANY OR ALL THE OTHER CODE IN CONNECTION WITH THE SOFTWARE, INCLUDING (WITHOUT LIMITATION) ANY WARRANTIES OF SATISFACTORY QUALITY OR FITNESS FOR A PARTICULAR PURPOSE. NO THIRD PARTY LICENSORS OF OTHER CODE SHALL HAVE ANY LIABILITY FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING WITHOUT LIMITATION LOST PROFITS), HOWEVER CAUSED AND WHETHER MADE UNDER CONTRACT, TORT OR OTHER LEGAL THEORY, ARISING IN ANY WAY OUT OF THE USE OR DISTRIBUTION OF THE OTHER CODE OR THE EXERCISE OF ANY RIGHTS GRANTED UNDER EITHER OR BOTH THIS LICENSE AND THE LEGAL TERMS APPLICABLE TO ANY SEPARATE FILES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES NT11603A Rev. 1.1 Page 3 of

4 APPLICABILITY TABLE PRODUCT GS2K based Modules For EVB /SKB Note: The features described in the present document are provided by the products equipped with the software versions equal or higher than the versions shown in the table. See also the Revision History chapter NT11603A Rev. 1.1 Page 4 of

5 Revision History Version Date Remarks 1.0 November 2016 Initial release 1.1 February 2018 Removed sections: 2.2 Measuring Deep Sleep Power 3.8 Measuring Standby Current Modified sections: 2.1 Measuring Standby Power to Measuring Standby and Deep Sleep Power 3.7 Measuring Deep Sleep Current to Measuring Deep Sleep and Standby Current 80560NT11603A Rev. 1.1 Page 5 of

6 Table of Contents NOTICE... 2 COPYRIGHTS COMPUTER SOFTWARE COPYRIGHTS... 2 USAGE AND DISCLOSURE RESTRICTIONS... 3 APPLICABILITY TABLE... 4 CHAPTER 1 INTRODUCTION PURPOSE... 9 CHAPTER 2 POWER MANAGEMENT STATES FOR EVB MEASURING STANDBY AND DEEP SLEEP POWER Standby Power Deep Sleep Power MEASURING OPERATING POWER CHAPTER 3 POWER MANAGEMENT STATES FOR SKB POWER MEASUREMENT CIRCUITRY BATTERY GAUGE CIRCUIT SKB POWER STATES AND AVERAGE CURRENT CONFIGURING THE SKB FOR CURRENT MEASUREMENT Building the S2W Firmware using SDK Builder Programming the S2W Firmware into the SKB Jumper Settings for Current Measurement Connecting the Bench Supply and Digital Multi-Meter Configuring the Serial Port MEASURING TRANSMIT CURRENT MEASURING RECEIVE CURRENT MEASURING DEEP SLEEP AND STANDBY CURRENT MEASURING PS-POLL AVERAGE CURRENT PS-POLL with Standby Average Current Measurement PS-POLL with Deep Sleep Average Current Measurement APPENDIX A BUILDING THE S2W FIRMWARE USING SDK BUILDER APPENDIX B PROGRAMMING SKB WITH GAINSPAN FIRMWARE APPENDIX C CONFIGURING SERIAL PORT FOR POWER MEASUREMENT NT11603A Rev. 1.1 Page 6 of

7 List of Figures Figure 1: Experimental Setup for Measuring GS2200M EVB3 REV1.0 Board Standby Power 11 Figure 2: Experimental Setup for Measuring GS2200M EVB3 REV1.0 Board Deep Sleep Power Figure 3: Tera Term VT COM Port Settings - Standby Mode Figure 4: Serial-to-Wi-Fi APP Message Within Tera Term Window Figure 5: Setting Standby Mode in Milliseconds Standby Mode Figure 6: Setting Module into Deep Sleep Mode Figure 7: Experimental Setup for Measuring EVB3.0 Board Operating Power Figure 8: GS2200MIZ Associated to AP in PS-Poll Mode with DTIM= Figure 9:Power Measurement Circuit Figure 10: Power Measurement Mode Switch Figure 11: Battery Gauge Circuit Figure 12: Current Profile in using PS-Polling with Standby between Beacons Figure 13: Current Profile using PS-Polling with Deep Sleep between Beacons Figure 14: SDK Builder Configuration Figure 15: SDK Builder Configuration Figure 16: SDK Builder Configuration Figure 17: Program Mode and GainSpan Flash Programmer Figure 18: Status of Firmware Programming Figure 19: Serial Port Settings Figure 20: Serial Port Output NT11603A Rev. 1.1 Page 7 of

8 List of Tables Table 1: Standby and Deep Sleep Mode Jumper Settings for EVB Table 2: Operating Power Measurement Jumper Settings for EVB Table 3: Power States Table 4: Recommended Jumper Settings for Power Measurements Table 5: Power Source Selection Table 6: AT Commands and Comments NT11603A Rev. 1.1 Page 8 of

9 Chapter 1 Introduction 1.1 PURPOSE This document describes a method for measuring the typical power consumption of a Sensor Node based on the GainSpan System-on-Chip (SoC), currently exemplified by the GS2000. All measurements described by this document can be performed with the GainSpan GS2011 Evaluation Boards (EVB) of the GS2011M EVB3 REV2.0 (noted by GS2xxxM EVB3 REV2.0 marking on PCB of evaluation board and a GS2011MIE, GS2011MIZ, or GS2011MIES and GS2200MIZ EVB3-REV1_0 marking on the label of the shield of the GainSpan module on the board). These boards are GainSpan SoC reference designs that can be powered by either a lab power supply or a standard USB power supply. They include all the peripheral circuitry required to power and clock the SoC, as well as on-board light and temperature sensors. Using any of the above evaluation boards and the Serial-to-Wi-Fi reference firmware applications as described by this document simplifies measurement of both Standby, Deep Sleep, and Operating power consumption. NOTE: The power measurement instructions in this document is based on the GS2200M EVB NT11603A Rev. 1.1 Page 9 of

10 Chapter 2 Power Management States for EVB3.0 The power consumption of the EVB boards is dominated by the GainSpan SoC itself. The power consumed by the SoC depends on the operations of its various system components. Note that the SoC Standby and Deep Sleep states are distinguished from other states by the deactivation of the high-speed 40 MHz crystal and 80 MHz RC oscillators, which both saves power in the clock oscillator and terminates high-speed switching in the remainder of the chip. In the Standby state, only the low-frequency ( khz) RTC module and associated circuitry are operating, and power consumption is greatly reduced. Power consumption is computed by multiplying measured voltage and power. Power consumption is typically measured by placing a small power measuring resistor in series with the power supply. This resistor must be scaled appropriately to provide enough gain to measure the power with sufficient accuracy, while at the same time, not dropping enough voltage to affect the experiment. The power consumption of the GainSpan GS2200 SoC varies over five orders of magnitude (from 4 μa to 300 ma) since different methods are being used for measuring Standby, Deep Sleep, and operating power. The methods to be used for performing measurements of each of these power draws are provided by the following sections of this document. 2.1 MEASURING STANDBY AND DEEP SLEEP POWER Standby Power Measurement The following procedure to measure standby power can be used with the modules GS2011 and GS2200M with shield markings GS2011M EVB3 and GS2200M EVB3 respectively on the evaluation boards. These boards incorporate modules GS2011MIE, GS2011MIZ, or GS2011MIES. To measure standby power, a 3.3 Volt DC power supply is connected to test points TP3 (+) and TP6 (GND) of the EVB3.0 board (TP3 is a yellow loop connector labeled BENCH 3V3, while TP6 is a brown loop connector labeled POWER MEAS SUPPLY GND) and an ammeter is connected to the two pins of J23 (after removing the jumper from this connector). The GS2200 module under test is then placed into standby mode. The ammeter measures the power drawn through the module VRTC supply which supplies the power to RTC (Real Time Clock) block. This is the only part of the module in operation while the module is in standby mode. The connections to be done on the GS2200 EVB 3 REV 1.0 board are as shown in Figure NT11603A Rev. 1.1 Page 10 of

11 Figure 1: Experimental Setup for Measuring GS2200M EVB3 REV1.0 Board Standby Power Deep Sleep Power Measurement The following procedure to measure deep sleep power can be used with the module GS2200M with shield marking GS2200M EVB3 REV 1.0 on evaluation board. To measure Deep Sleep power, a 3.3 Volt DC power supply is connected to test points TP3 (+) and TP6 (GND) of the EVB board (TP3 is a yellow loop connector labeled BENCH 3V3, while TP6 is a brown loop connector labeled POWER MEAS SUPPLY GND) and a voltmeter is connected to the two pins of J14, which have the voltmeter measure the voltage across the 1 Ohm R25 resistor which is placed in series to the GS2200 module on the EVB. The voltmeter is left connected to the two pins of this connector while the jumper for this connector is still left connected shorting those two pins. The GS2200 module under test is then placed into deep sleep mode by issuing the proper Serial to Wi-Fi command and the jumper is removed from J14. The voltmeter will then measure the voltage across the 1 Ohm resistor and this measured voltage is then equal to the power consumed by the GS2200 module while it is in deep sleep mode (as the voltage being measured is across a 1 Ohm resistor in series to the GS2200 module). The connections to be done on the GS2200 EVB 3 REV1.0 board as shown in Figure NT11603A Rev. 1.1 Page 11 of

12 Figure 2: Experimental Setup for Measuring GS2200M EVB3 REV1.0 Board Deep Sleep Power To perform the above experiments, set up the experimental apparatus as follows: 1. Configure the EVB3.0 Board with GainSpan Serial-to-Wi-Fi Application Firmware (AFW), as provided with the Evaluation Kit. Loading of the Serial-to-Wi-Fi firmware can be done under USB power. 2. Set the DC supply output voltage to 3.3V. Set the power limit to 500 ma. 3. Turn OFF the DC supply. 4. Set the jumpers and connectors of the EVB3 REV1.0 board (see Table 1) NT11603A Rev. 1.1 Page 12 of

13 Table 1: Standby and Deep Sleep Mode Jumper Settings for EVB3.0 Jumper Setting Description J1 Leave all pins of J1 disconnected (do not place any jumpers on J1) N/A J2 Leave all pins of J2 disconnected (do not place any jumpers on J2) N/A J4 J13 J14 Leave all jumpers connected for J4 with the exception of the following two jumpers: - Remove the jumper placed between pins 1 and 2 (far left of J4 labeled V_LED) - Remove the jumper placed between pins 37 and 38 (second jumper from right to left of J4 labeled VFLASH) - Remove the jumper placed between pins 11 and 12 (labeled VIN_3V3_LED) - Removes the jumper placed between pins 13 and 14 (labeled 3V3_LED) - Remove the jumper placed between pins 39 and 40 (labeled SEN_PWR). Leave jumper in place between pins 1 and 2 for J13 at start of test. For Standby: Leave jumper in place between pins 1 and 2 for J14 at start of test. For Deep Sleep: Connect GND terminal of voltmeter to left pin of connector J14 and connect positive (+) terminal of voltmeter to right pin of connector J14. - Removing the V_LED jumper will remove power from the EVB board s LEDs. - Removing the VFLASH jumper will remove power from the EVB board s flash memory as well as from the apple authentication chip (the second is only valid for EVB boards that include this chip). - Removing the VIN_3V3_LED and 3V3_LED jumper disconnects LEDs D8 and D9. - Removing the SEN_PWR jumper disconnects the power to the sensors. Leaves GPIO25/UART0_RTS connected. Shorts 1 Ohm resistor used to measure active mode power consumption. Connects voltmeter to measure voltage across 1 Ohm resistor after placing module in deep sleep. J15 Leave jumper in place between pins 1 and 2 for J15 at start of test. Shorts 100 Ohm resistor used to measure deep sleep power consumption NT11603A Rev. 1.1 Page 13 of

14 Jumper Setting Description J23 J24 J29 J30 J31 For Standby: Connect leftmost pin of J23 to GND terminal of ammeter and rightmost pin of J23 to positive (+) terminal of ammeter. For Deep Sleep: Leave jumper in place between pins 1 and 2 for J23 at start of test. Leave J24 pins disconnected (remove jumper if one is present). Leave jumper between pins 1 and 2 (closer to module on evaluation board). Place jumper between pins 1 and 2 (Logic High 3.3 V). Place jumper between pins 2 and 3 (pins marked as Bench 3V3). Connects Ammeter in line between 3V3 and GS2011 VRTC power supply pin for standby power measurement. Connects module VRTC pin to 3V3. Leaves GPIO25 Program select input in Disconnects GPIO8/I2C_DATA. N/A Sets the voltage for logic high for the module. Leaving the pins between 2 and 3 (Logic High 1.8 V) does not have any impact on the power measurement. Selects a lab power supply (through test points TP2 and TP16) instead of USB connector as the power supply. J32 J33 Leave jumper placed between pins 2 and 3 of J32 (pins marked as STANDBY for J32 on evaluation board). Leave J33 pins disconnected (remove jumper if one is present). Enables module to operate in standby mode when needed (instead of setting it to operate in always on mode as selected by placing a jumper between pins 1 and 2 on J32). Disconnect GPIO9/I2C_CLK disconnected. J34 Leave jumper between pins 1 and 2. N/A The VREG jumper decides the input power to the module. J35 Choose one of the two options for the jumper position: - Place jumper between pins 1 and 2 - Place jumper between pins 2 and 3. - If the jumper is placed between pins 1 and 2, the on-board regulator is bypassed and the input to the module is 3.3 V - If the jumper is placed between pins 2 and 3, the on-board regulator is used and the input is 1.8 V NT11603A Rev. 1.1 Page 14 of

15 Jumper Setting Description Measure power on both settings to decide whether to use an on-board regulator for the design. J36 Leave J36 pins disconnected (remove jumper if one is present). N/A J37 Leave jumper between pins 2 and 3. N/A 5. After connecting the power supply, voltmeter/ammeter, and configuring the EVB jumpers as described by the table above, continue with the steps below: 6. Set the SW6 switch on the Eval board to OFF position. 7. Connect the USB0 port on your EVB3.0 board to your computer through a USB cable. 8. Start a terminal program such as Tera Term VT, HyperTerminal, or Putty and configure it to connect to the evaluation board you are testing according to the serial port settings specified by the firmware that was loaded onto the module on the EVB3.0 board. As a reference, GainSpan s default Serial-to-Wi-Fi UART settings are 9600 bps, N/8/1 so for firmware with those settings, you should set your terminal program to the serial port settings (see Figure 3). Figure 3: Tera Term VT COM Port Settings - Standby Mode 80560NT11603A Rev. 1.1 Page 15 of

16 9. Turn ON the DC supply and set switch SW6 on the EVB 3.0 board to the ON position. The following message is displayed on your serial terminal (see Figure 4). Figure 4: Serial-to-Wi-Fi APP Message Within Tera Term Window 10. For Standby mode: Through the serial terminal program, issue the following command to the Serial-to-Wi- Fi firmware on the board. AT+PSSTBY= This will set the board into standby mode for a period of 99,999,999 milliseconds, which provides enough time for a voltmeter measurement to be completed. The following command is issued (see Figure 5) NT11603A Rev. 1.1 Page 16 of

17 Figure 5: Setting Standby Mode in Milliseconds Standby Mode Once the above command has been issued, and while the board is still in standby mode (the message Out of StandBy-Timer is not received from the board on the serial terminal) measure the observed power on the ammeter. This power will be the module s standby power. Measured standby power consumption for a GS2200MIZ 3.3 module EVB3.0 board running standard release candidate firmware (obtained from GainSpan s website SDK Builder tool) when powered from a 3.3V DC supply was ~8 μa. For Deep Sleep Mode: Through the serial terminal program issue the following command to the Serial-to-Wi-Fi firmware on the board. AT+PSDPSLEEP This will set the board into deep sleep mode (see Figure 6) NT11603A Rev. 1.1 Page 17 of

18 Figure 6: Setting Module into Deep Sleep Mode Once the above command has been issued, and while the board is still in deep sleep mode (the message Out of Deep Sleep is not received from the board on the serial terminal) measure the observed voltage on the voltmeter. This voltage will be equivalent to the module s deep sleep power, as the voltage is being measured across the R25 1 Ohm resistor which is placed in line between the power supply and the GS2200 module in the EVB board. Measured deep sleep power consumption for a GS2200MIZ 3.3 module EVB3.0 board running standard GA firmware (obtained from GainSpan website SDK Builder tool) when powered from a 3.3V DC supply was 485 μa (the voltage measured by the voltmeter following the above procedure was 485 μvolts). Note: - Ensure that you use a voltmeter with enough decimal digits to carry out the measurement. In general, a voltmeter that measures voltages with three-digit precision in millivolts is sufficient to conduct this measurement. - This measurement can also be carried out with a Voltmeter measuring the voltage across the J15 DP_SLP resistor in the EVB board which is a 100 Ohm resistor. Doing the measurement using this resistor provides better precision (due to the measured voltage multiplying the observed power by 100 Ohms), however, it must be noted that with standard Serial to Wi-Fi firmware, the firmware will periodically wake up from deep sleep mode to perform network maintenance tasks and, by waking up from this state and powering on the system s CPUs, this will increase the power draw seen from the GS2200 module, which may result in a larger voltage drop across the 100 Ohm resistor and can, in turn cause the system to reset due to an under voltage condition. Thus, for 80560NT11603A Rev. 1.1 Page 18 of

19 general measurements, use of the J14 ACTIVE resistor as stated in the procedure above is recommended. 2.2 MEASURING OPERATING POWER The following procedure to measure the power consumption of a GainSpan module in active operating mode can be used with the GS2200 EVB3 boards (noted by GS2200M-EVB3 REV 1.0 marking on PCB of evaluation board and a GS2200 MIZ marking on the label on the shield of the GainSpan module on the board). The procedure is very similar to the static measurements of deep sleep mode shown in the previous section of this document, with very similar jumper and connection settings to those used in the previous section with the main differences being that instead of using a voltmeter as in the deep sleep power measurement procedure of the previous section, an oscilloscope will be used to measure the power consumption of the module while it switches between operating modes (standby, deep sleep, processor(s) enabled or processors + radio enabled). The oscilloscope will be used to provide a graphic trace of the power consumption of the module while it performs any given action (for example, associating to an access point, transmitting data, staying associated to an access point in PS-Poll mode, and so on) and, while doing so switching between its operating modes (standby, deep sleep, processor(s) on, radio on, etc.). The setup for the active operating power measurement (see Figure 7). Figure 7: Experimental Setup for Measuring EVB3.0 Board Operating Power 80560NT11603A Rev. 1.1 Page 19 of

20 The setup looks as follows: To perform this experiment, set up the experimental apparatus as follows: 1. Configure the EVB3.0 Board with the desired firmware. 2. Set the DC supply output voltage to 3.3V. Set the power limit to 500 ma. 3. Turn OFF the DC supply. 4. Set the jumpers and connectors of the EVB3.0 board (see Table 2) NT11603A Rev. 1.1 Page 20 of

21 Table 2: Operating Power Measurement Jumper Settings for EVB3.0 Jumper Setting Description J1 Leave all pins of J1 disconnected (do not place any jumpers on J1) N/A J2 Leave all pins of J2 disconnected (do not place any jumpers on J2) N/A J4 J13 J14 J15 J23 J24 Leave all jumpers connected for J4 with the exception of the following two jumpers: - Remove the jumper placed between pins 1 and 2 (far left of J4 labeled V_LED) - Remove the jumper placed between pins 37 and 38 (second jumper from right to left of J4 labeled VFLASH) - Remove the jumper placed between pins 11 and 12 (labeled VIN_3V3_LED) - Removes the jumper placed between pins 13 and 14 (labeled 3V3_LED) - Remove the jumper placed between pins 39 and 40 (labeled SEN_PWR) Leave jumper in place between pins 1 and 2 for J13 at start of test. Connect GND terminal of voltmeter to left pin of connector J14, connect positive (+) terminal of voltmeter to right pin of connector J14. Leave jumper in place between pins 1 and 2 for J15 at start of test. Connect leftmost pin of J23 to GND terminal of ammeter and rightmost pin of J23 to + terminal of ammeter. Leave J24 pins disconnected (remove jumper if one is present). - Removing the V_LED jumper will remove power from the EVB board s LEDs. - Removing the VFLASH jumper will remove power from the EVB board s flash memory as well as from the apple authentication chip (the second is only valid for EVB boards that include this chip). - Removing the VIN_3V3_LED and 3V3_LED jumper disconnects LEDs D8 and D9. - Removing the SEN_PWR jumper disconnects the power to the sensors. Leaves GPIO25/UART0_RTS connected. Connects voltmeter to measure voltage across 1 Ohm resistor after placing module in deep sleep Shorts 100 Ohm resistor used to measure deep sleep power consumption. Connects Ammeter in line between 3V3 and GS2011 VRTC power supply pin for standby power measurement Leaves GPIO25 Program select input in Disconnects GPIO8/I2C_DATA 80560NT11603A Rev. 1.1 Page 21 of

22 J29 J30 J31 Leave jumper between pins 1 and 2 (closer to module on evaluation board). Leave jumper between pins 1 and 2 (Logic High 3.3 V) Place jumper between pins 2 and 3 (pins marked as Bench 3V3 and closer to module on evaluation board). N/A Sets the voltage for logic high for the module. Leaving the pins between 2 and 3 (Logic High 1.8 V) does not have any impact on the power measurement. Selects a lab power supply (through test points TP2 and TP16) instead of USB connector as the power supply. J32 J33 Leave jumper placed between pins 2 and 3 of J32 (pins marked as STANDBY for J32 on evaluation board). Leave J33 pins disconnected (remove jumper if one is present). Enables module to operate in standby mode when needed (instead of setting it to operate in always on mode as selected by placing a jumper between pins 1 and 2 on J32). Disconnect GPIO9/I2C_CLK disconnected. J34 Leave jumper between pins 1 and 2 N/A The VREG jumper decides the input power to the module. J35 J36 Choose one of the two options for the jumper position: - Place jumper between pins 1 and 2 - Place jumper between pins 2 and 3. Leave J36 pins disconnected (remove jumper if one is present) - If the jumper is placed between pins 1 and 2, the on-board regulator is bypassed and the input to the module is 3.3 V. - If the jumper is placed between pins 2 and 3, the on-board regulator is used and the imput is 1.8 V. Measure power on both settings to decide whether to use an on-board regulator for the design. N/A J37 Leave jumper between pins 2 and 3 N/A 5. Either leave the oscilloscope free-running with a long capture period (5 seconds per division will be a good selection for this purpose), or configure the oscilloscope trigger as needed for the test in question (for example, if you want to start capturing when the radio is turned on, set the trigger to rising edge and trigger threshold that is above 50 milliamperes but below 100 milliamperes) so that it will start capturing at the moment the GainSpan chip reaches the desired state NT11603A Rev. 1.1 Page 22 of

23 6. It is also recommended to set the Oscilloscope to 50 mv per division, as that will give enough resolution to observe all operating modes, but if zooming into a mode is desired, a different amplitude setting may be selected for the oscilloscope as desired. 7. If a serial connection is needed to the EVB to measure the state of interest (for example, if you need to issue Serial-to-Wi-Fi commands to ask the module to associate to an access point) Connect the USB0 port on your EVB board to your computer through a USB cable. 8. Power on the DC supply and perform any needed setup to reach the desired operating state (whether that is issuing Serial to Wi-Fi commands via a serial terminal or any other actions on other devices - access points, other Wi-Fi clients, any network servers, and so on). 9. As a final step before measuring the power consumption on the scope, make sure that if you have a USB cable connected to either the USB0 or USB1 ports on the EVB board those are disconnected prior to conducting the measurement on the oscilloscope, as depending on what is connected to these ports, they can create an alternate ground that can impact the performed measurement. 10. The instantaneous power consumption will be observed on the oscilloscope as I = Oscilloscope Voltage Measurement / J14 Active Resistance = I = Oscilloscope Voltage Measurement / 1, in other words, the voltage seen in the oscilloscope will directly be the module s instantaneous power consumption. As a reference, the trace provided (see Figure 8) was obtained by associating a GS2200MIZ module to an access point and operating in PS-Poll mode with DTIM=1 periodicity with the above procedure and the following equipment: Oscilloscope: Agilent MS06034A Access Point: Linksys E1000 V2 with firmware version GainSpan Evaluation Board: GS2200MIE-EVB3 GainSpan Wireless Firmware: RC GainSpan Application software: RC Serial-to-Wi-Fi 80560NT11603A Rev. 1.1 Page 23 of

24 Figure 8: GS2200MIZ Associated to AP in PS-Poll Mode with DTIM= NT11603A Rev. 1.1 Page 24 of

25 Chapter 3 Power Management States for SKB The GS2200M Starter Kit Board (SKB) is an easy to use evaluation and development platform for GS2200M module-based products. It includes built-in power measurement features to facilitate estimated power consumption and battery life of the product. Power consumption is computed by multiplying measured voltage and current. This document specifies the current measurement aspects of the GS2200M Starter Kit Board (SKB). The GS2200M module s supply voltage is constant ~3.3V and the Current consumption varies with time. This document describes how to measure current consumption of the GS2200M module using various features of the GS2200M SKB. These techniques may be used to estimate power consumption and battery life of a product that will utilize the GS2200M. 3.1 POWER MEASUREMENT CIRCUITRY The power measurement feature provides measuring the power drawn by the GS2200M and the external 1.8V regulator. It excludes the power consumed by the sensors, other peripherals and regulators. The power measurement circuitry as shown in Figure 9, consists of two shunt resistor options, selectable by switch SW6. These are in series with the GS2200M, after the sensor and peripheral load is excluded from power measurements. A current measuring amplifier amplifies the voltage drop over the selected shunt resistor to generate the power measurement signal. Power measurement at the bench supply source will not be accurate because they include power consumed by the other components on the board including LEDs, sensors, and the power measurement circuit. Hence bench supply source for measuring the power is not used. Figure 9:Power Measurement Circuit 80560NT11603A Rev. 1.1 Page 25 of

26 Figure 10: Power Measurement Mode Switch The power measurement mode switch (SW6), as shown in Figure 10, selects between the two shunt resistors for Active (coarse - 100mA/V) and Sleep (fine - 125uA/V) measurement. This yields measurement ranges of 0 ~400mA or 0 ~500uA, respectively. The switch is makebefore-break such that it can be switched from Active to Sleep position after the GS2200M has entered deep-sleep, standby or hibernate without causing a brownout. The output of the amplifier is routed to the PMEAS test point (TP2). Use the PMEAS Test Point and the GND Test Point (TP3) to attach an oscilloscope or digital multi-meter. 3.2 BATTERY GAUGE CIRCUIT The battery gauge circuit provides for measuring battery voltage under load. This may be used to estimate the remaining battery life in the Figure 11, the measurement circuit is controlled by GPIO10. ADC0 is used to measure the voltage. Setting GPIO10 high enables measurement mode by switching on a load (resistor to ground) on the battery and switching on the connection to ADC0. Jumper J11 enables or disables the battery gauge. Removing the jumper allows GPIO10 and ADC0 to be used for other purposes. Figure 11: Battery Gauge Circuit NOTE: ADC inputs to GS2200M may not be driven when GS2200M is in standby, therefore the ADC0 connection must be turned off when the GS2200M s VDDIO supply is not powered. This is assured by using a GPIO to turn ON the ADC input NT11603A Rev. 1.1 Page 26 of

27 3.3 SKB POWER STATES AND AVERAGE CURRENT GS2200M module used in SKB, supports the following power states/modes as described in Table 3. Each mode consumes different amount of current. Typical average current consumption for each mode is given below: Table 3: Power States Power State Typical Average Current Comments Hibernate 260 na SKB does not support this measurement Standby 4-8 µa Deep Sleep µa RX - Active TX - Active 85 ma 250 ma NOTE: Average current can vary from module to module. It can also depend on the software version. Please refer to the GS2200M Data Sheet for more information on the power states. The above mentioned average current consumption is based on GEPS software. 3.4 CONFIGURING THE SKB FOR CURRENT MEASUREMENT In order to measure current, SKB should be loaded with an appropriate firmware. The SKB hardware jumpers must be configured to select the proper power source as well as the power measurement mode. The following sections gives these configurations: Building the S2W Firmware using SDK Builder Please refer to Appendix A for instructions on how to build the S2W firmware using GainSpan SDK Builder Programming the S2W Firmware into the SKB Please refer to Appendix B for instructions on how to program the S2W firmware using GS Flash Programming tool Jumper Settings for Current Measurement The recommended settings for other jumpers for power measurement is described in Table 4. Once the power source is selected for measuring the current, review the settings using the below table: 80560NT11603A Rev. 1.1 Page 27 of

28 Table 4: Recommended Jumper Settings for Power Measurements Header Jumper Settings Comments J18 [1-2] and [7-8] Others: Do not care Enable USB serial port connections to UART0 TX and RX signals J20 Do not care SPI master/slave jumpers J11 Do not care Battery Gauge enable jumper J14 1.8V [2-3] VREG power source. Select 1.8V [2-3] for lowest power. Select 3.3V [1-2] if omitting external 1.8V regulator from end product design. J15 Do not care Power source for the sensors J16 Do not care Power LED enable jumper Connecting the Bench Supply and Digital Multi - Meter 1. Set power source jumpers to Bench Supply, as per the below table: Table 5: Power Source Selection Power Source J19 J12 J13 Bench Supply Don t Care Don t Care BENCH [1-2] Battery Don t Care BATT [2-3] [2-3] USB USB [1-2] [1-2] [2-3] Arduino +5V [J3 pin 5] +5V [2-3] [1-2] [2-3] 2. Set the DC supply output voltage to 3.3V and set the current limit to 500 ma. 3. Turn OFF the DC supply. 4. Connect the positive terminal of bench supply to the 3.3V Test Point [TP4] and the negative terminal to GND Test Point [TP5] on the SKB. 5. Connect the Digital Multimeter s (DMM) positive terminal to the PMEAS Test Point [TP2] and the negative COM terminal to the GND Test Point [TP3] NT11603A Rev. 1.1 Page 28 of

29 Make sure that the power measurement mode switch [SW6] is set to the ACTIVE position Configuring the Serial Port Please refer to Appendix C for instructions on how to configure the serial port. 3.5 MEASURING TRANSMIT CURRENT Following steps are used to measure the transmit power current of b/g/n base mode that is 1Mbps/6Mbps/6.5Mbps transmit date rates. 1. Set the power measurement mode switch [SW6] to the ACTIVE position. 2. Power cycle the SKB using the switch on the bench supply or, if bench supply is not used, SKB s power switch [SW5] can be used instead. 3. Issue the following AT commands to the SKB using the serial terminal program. (These commands will generate a continuous b transmit signal at 1Mbps.) 4. The DMM will display the average transmit current. Table 6: AT Commands and Comments AT Commands at+wrfteststart at+wtx100test=6,0,15,0,0,0,0,1,1,0,0,0,0,1 AT+WRFTESTSTOP AT+WRFTESTSTART at+wtx100test=6,0,21,0,0,0,0,1,0,0,0,1,3,0 AT+WRFTESTSTOP AT+WRFTESTSTART at+wtx100test=6,0,21,0,0,0,0,1,0,0,0,1,0,2 Comments b transmit signal at 1Mbps Expected Average TX current - ~215 ma g transmit signal at 6Mbps Expected Average TX current - ~265 ma n transmit signal at MCS0 Expected Average TX current - ~265 ma NOTE: Please refer GS2200M S2W Adapter Command Reference Guide for details on the above AT commands as well as generating signals at various data rates. 3.6 MEASURING RECEIVE CURRENT Following are the steps used to measure Receive Current: 1. Set the power measurement mode switch [SW6] to the ACTIVE position. 2. Power cycle the SKB NT11603A Rev. 1.1 Page 29 of

30 3. Issue the following AT commands to the SKB using the serial terminal program. (These commands will turn the receiver ON and enable asynchronous frame reception) 4. DMM will display the average receive current. AT Commands at+wrfteststart at+wrxtest=6,0, ,00:00:00:00:00:00,0 Comments Expected Average TX current - ~85 ma NOTE: Please refer to the GS2200M S2W Adapter Command Reference Guide for details on the above AT commands. 3.7 MEASURING DEEP SLEEP AND STANDBY CURRENT Following are the steps used to measure Deep Sleep/Standby current for GS2200M SKB. 1. Set the power measurement mode switch [SW6] to the ACTIVE position. 2. Power cycle the SKB. 3. Issue the following AT commands to the SKB using the serial terminal program. (This command will put the module into Deep Sleep/Standby Mode.) 4. Set the power measurement mode switch [SW6] to the SLEEP position. 5. Measure the voltage, V0 across test points TP2 and TP3 using DMM. Sleep Mode AT Commands Comments Deep Sleep at+psdpsleep= ,1,1 Expected Deep Sleep Current - ~600 µa Standby at+psstby= ,1,1 Expected Standby Current - ~8 µa NOTE: Please refer to the GS2200M S2W Adapter Command Reference Guide for details on the above AT commands. Use the following equation to calculate the Deep Sleep/Standby current: Where: I = (K Vo) Ios 80560NT11603A Rev. 1.1 Page 30 of

31 I Current Vo - Measured voltage K - Scale factor (based on SW6 position, which is 100mA/V for ACTIVE and 125µA/V for SLEEP) Ios - Offset current that flows into the -IN pin of the amplifier (approximately 14µA). This can be calculated by measuring the voltage drop across R25 on SKB. Example: STANDBY current: I = (125µA/V * 175.5mV) - 14µA I = µA - 14µA I = 7.93µA Example: DEEP SLEEP current: I = (125µA/V * 3.487V) - 14µA I = µA - 14µA I = µA 3.8 MEASURING PS-POLL AVERAGE CURRENT During PS-POLL the current can vary from few µa to 100 ma very rapidly. To capture these variations an instrument with very high sampling rate and dynamic range is required. Usage of DMM or scope that can sample at high frequency, over a large dynamic range and average over a long period is suggested. This could be connected to PMEAS to integrate the power curve over a long period. Another option is using the 6705B DC Power Analyzer from Key Sight or other instruments with similar capabilities for accurate average current measurements. However, scope to measure the average current and a bench supply to power the SKB is used, as in previous sections PS-POLL with Standby Average Current Measurement 1. Power cycle the SKB. 2. Set the power measurement mode switch [SW6] to the ACTIVE position. 3. Issue the following AT commands to the SKB using the serial terminal program. (These commands will put the module into PS-POLL mode and Standby in between.) 4. Use an oscilloscope to capture the current profile similar to the one shown in Figure NT11603A Rev. 1.1 Page 31 of

32 AT Commands at+wrxactive=0 at+wrxps=0 at+wkeepalive=0 at+wieeepspoll=2,,2,5 at+wieeepspoll=1 Comments Standby between PS-POLL & DTIM interval 5 Note You can try different DTIM intervals by changing the value 5 to desired DTIM interval. For example at+wieeepspoll=2,,2,3 will use DTIM interval of 3 at+ndhcp=1 at+wa=appleextreme at+psstbybwbeaconconf=0,1 at+psstbybwbeacon=1 Expected Average Current for DTIM 5 - ~1 ma NOTE: Please refer to the GS2200M S2W Adapter Command Reference Guide for details on the above AT commands. Based on the above AT commands, the SKB exits from standby every 510ms (5 th Beacon based on beacon interval of 102ms). As shown in Figure 12, the GS2200M wakes up from standby at P1 to turn the receiver ON and receive the beacon, then goes back into standby at P2. In order to calculate the average current drawn, the average current from time P1 through time P2 is accounted. Based on previous measurements, we know the GS2200M consumes 5-8 µa in standby mode. This data can be used and collected while the GS2200M is active to calculate the average current consumed over the entire polling cycle from the start of the cycle to the start of the next polling cycle. Based on polling every 510ms, the time in standby will be 510 (P2 P1) ms. Average current consumed over one polling cycle is calculated using the following steps. 1. Export the data from your oscilloscope to a CSV file. 2. Import the CSV data into a spreadsheet program. 3. Scan the data and record the times P1 (where measured voltage first rises from the standby level) and P2 (where measured voltage returns to the standby level). 4. Use the spreadsheet to calculate the average of measurements taken between times P1 and P2. Define this value as Vactive, the average voltage while the GS2200M is active. 5. Calculate the average current over an entire polling cycle using the following formulas: Iavg = (Tactive * Iactive + Tstby * Istby) / (Tactive + Tstby) or Iavg = ((P2 P1)ms * (Vactive * 100mA/V) + (510ms (P2 P1)ms) IstbymA) / 510ms 80560NT11603A Rev. 1.1 Page 32 of

33 Figure 12: Current Profile in using PS-Polling with Standby between Beacons PS-POLL with Deep Sleep Average Current Measurement 1. Power cycle the SKB. 2. Issue the following AT commands to the SKB using the serial terminal program. (These commands will put the module into PS-POLL mode and Standby in between.) 3. Use a power analyzer or DMM or Oscilloscope to measure measurement. AT Commands Comments at+wrxactive=0 at+wrxps=0 at+wieeepspoll=2,,2,1 at+wieeepspoll=1 at+wkeepalive=0 at+ndhcp=1 at+wa=appleextreme Deep Sleep between PS-POLL and DTIM interval 1 Custom wake up independent of AP DTIM setting. Note You can try different DTIM intervals by changing the value 1 to desired DTIM interval. For example at+wieeepspoll=2,,2,3 will use DTIM interval of 3. Expected Deep Sleep Current for DTIM 1 - ~3.5 ma at+psdpsleep= ,1,1,1 NOTE: Please refer to the GS2200M S2W Adapter Command Reference Guide for details on the above AT commands. Based on the above set of AT commands, SKB exits from Deep Sleep every 102ms (beacon interval is 102ms). As shown in Figure 13, the SKB turns ON the receiver to receive the Beacon and at P2, it goes back into Deep Sleep. In order to calculate the average current drawn, average 80560NT11603A Rev. 1.1 Page 33 of

34 current from P1 through P2 is accounted. Based on previous measurements, GS2200M consumes ~400 µa in standby mode. This data can be used and collected while the GS2200M is active to calculate the average current consumed over the entire polling cycle from the beginning of on cycle to the beginning of the next polling cycle. Based on polling every 102ms, the time in standby is 102 (P2 P1) ms. Figure 13: Current Profile using PS-Polling with Deep Sleep between Beacons To calculate the average current consumed over one polling cycle use the following steps. 1. Export the data from the oscilloscope to a CSV file. 2. Import the CSV data into a spreadsheet program. 3. Scan the data and record the times P1 (where measured voltage first rises from the standby level) and P2 (where measured voltage returns to the standby level). 4. Use the spreadsheet to calculate the average of measurements taken between times P1 and P2. Name tis value as Vactive, the average voltage while the GS2200M is active. 5. Calculate the average current over an entire polling cycle using the following formulas: Iavg = (Tactive * Iactive + TDeep Sleep * IDeep Sleep) / (Tactive + TDeep Sleep) or Iavg = ((P2 P1)ms * (Vactive * 100mA/V) + (102ms (P2 P1)ms) IDeep SleepmA) / 102ms 80560NT11603A Rev. 1.1 Page 34 of

35 Appendix A Building the S2W Firmware using SDK Builder To build S2W, login to GainSpan customer portal and build the firmware. Please refer to the SDK Builder User Guide for detailed instructions. While building the S2W application, ensure the following features are selected, as shown in Figure 14, Figure 15, and Figure 16. Figure 14: SDK Builder Configuration Figure 15: SDK Builder Configuration 80560NT11603A Rev. 1.1 Page 35 of

36 Figure 16: SDK Builder Configuration 80560NT11603A Rev. 1.1 Page 36 of

37 Appendix B Programming SKB with GainSpan Firmware Once the S2W firmware is built, as described in Appendix A, program the SKB with the firmware provided in gs2200_s2w_5.3.0.bin. Connect the mini-usb cable to the UART port on the SKB and another end to the PC. Turn ON the SKB through USB. In that case, J19 jumper should be set to USB as a source of power and SW6 switch must be set to ACTIVE. Turn the SKB ON by setting SW5 switch to ON position. Once the USB port is enumerated (if using for the first time), then program the SKB. Launch the GainSpan Serial Flash Programmer application from \Tools\GS_programming_tool. Select UART to select interface and select the appropriate UART port. If baud rate is chosen, as shown in the Figure 14, press and hold both PROGRAM [SW2] switch and RESET [SW4] switch, then release PROGRAM SW4 switch. Alternatively, if baud rate is chosen, press and hold both PROGRAM and RESTORE [SW1] then release the RESET button. Figure 17: Program Mode and GainSpan Flash Programmer Once the SKB is detected successfully by the GainSpan Flash Programmer, select the superblock to be used Super Block, and then select the SKB firmware under Current FW Version. Serial Flash Programmer displays, if a valid superblock and firmware is selected. Now 80560NT11603A Rev. 1.1 Page 37 of

38 click Erase and Program to program the SKB with selected firmware. After successful programming Finished Programming Module Flash message is displayed as shown in Figure 18. Figure 18: Status of Firmware Programming 80560NT11603A Rev. 1.1 Page 38 of

39 Appendix C Configuring Serial Port for Power Measurement 1. Connect the USB port on the SKB board to the computer through a USB cable. 2. Start a terminal program (Tera Term VT, HyperTerminal, or Putty). 3. Configure the terminal to connect to the SKB per the serial port settings specified by the firmware which is loaded onto the module on the SKB. As a reference, GainSpan s default Serial-to-Wi-Fi UART settings is 9600 bps, N/8/1 as shown in Figure 19. Figure 19: Serial Port Settings Turn ON the bench supply. (if power source other than a bench supply is used, turn it ON by switching the power switch [SW5] to the ON position). The following message is displayed on the serial terminal after switching ON the power (see Figure 20) NT11603A Rev. 1.1 Page 39 of