EVALUATION BOARD DATA SHEET EV142

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1 EV2 Evaluation Board for the AAT272. A Step-Up Current Regulator Introduction The AAT272 EVAL board demonstrates the functionality of the AAT272 and its application as a high current white LED flash driver. The device provides excellent efficiency for both flash and movie modes. Two LED channels are provided with excellent current matching. By utilizing the two LED channels, better light efficiency can be achieved and delivered for combined drive current of 00mA (70mA on each channel). Conversely, one flash LED may be driven with 00mA by combining the two flash currents sinks to drive a single LED. Through the I 2 C interface, the AAT272 can be programmed with different movie mode currents, safety timer, individual channel On/Off and flash mode to movie mode ratio. This document describes the evaluation board and its accompanying user interface. In addition, a brief Getting Started section has been included to help the user begin operating the evaluation board. A schematic of the complete circuit is shown in Figures and. The actual board layout is also provided in Figures 6 and 7. For additional operation device details and I 2 C programming information, please consult the AAT272 product datasheet. Getting Started Power and IC Enable Connect an external power source (.0V-.2V, typical battery operating range) to the VIN and GND terminals. A jumper labeled JP7 is inline with the terminal VIN to turn power ON/OFF, place the jumper on JP7 to the ON position. The red LED should illuminate, indicating that power has been applied to the circuit. There is an additional jumper labeled JP that enables the AAT272. Once the AAT272 is enabled, the LEDs will turn on as movie mode. To turn off the LEDs, press all three buttons (SW, SW2 and SW) together. Preliminary Board Set-Up LED Drive Current The AAT272 has been set up and tested to provide 70mA maximum current for each current sink FLA and FLB. The maximum current sink current is set by R and has been set to 07kΩ for a maximum LED drive current of 70mA. For maximum drive current level below 70mA, R may be adjusted to a higher resistance value. Refer to the AAT272 datasheet for a table of set resistor values to program a desired flash current other than 00mA. The two current sinks can be operated independently to provide up to 70mA of LED drive control. The two current sinks may also be connected in parallel to sum the maximum LED drive current up to 00mA for one flash LED. Flash Timer The maximum flash duration is set by the capacitor C. The maximum flash time has been set to 20ms using a nf ceramic capacitor. C may be adjusted to increase or decrease the maximum full current flash time. The approximate flash time can be set by the following capacitor values: C =.7nF: 7.ms C = nf: 20ms C = 7nF: 7ms C = 7nF: 600ms Since the timeout timer is a function of input voltage, the maximum timeout time can vary over the specified 2.7V to.v input voltage range. As input voltage increases, the timeout function will decrease. Skyworks Solutions, Inc. Phone [78] Fax [78] sales@skyworksinc.com B Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. August 7, 202

2 Current and Voltage Measurement EVALUATION BOARD DATA SHEET EV2 Evaluation Board for the AAT272. A Step-Up Current Regulator The AAT272 evaluation board has been designed with several jumpers which may be removed to measure system input and LED drive currents. The use of an oscilloscope and current probes are strongly suggested for measuring LED flash current due to the transient nature of this measurement and to reduce measurement errors that would be induced by placing an ammeter in the circuit. Jumpers JP and JP2: LED current measurement point. To measure LED current, remove the 0Ω jumpers and replace with a short loop of wire that is large enough in diameter to connect an oscilloscope current probe. If two current probes are available, the LED flash current for FL and FL2 can be observed simultaneously. Jumper JP8: Input supply voltage and current can be monitored at JP8. Due to the transient nature of circuit operation, it is suggested to use a current probe to observe the circuit input current. To measure the input current, remove the 0Ω jumper at JP8 and replace with a short wire loop to connect an oscilloscope current probe. The Input supply voltage may be probed at JP8 with either an oscilloscope or multimeter. Jumpers JP and JP2: Remove and replace with a short loop of wire to measure LED current with a current probe Jumper JP8: Remove and replace with a short loop of wire to measure input current with a current probe Figure : Current and Voltage Measurement Points. I 2 C Interface and Control JP and JP6 allow probing and connection to the two I 2 C interface data lines, JP for and JP6 for. I 2 C interface data is programmed by the microcontroller U2 and its associated push button function switches SW, SW2 and SW. One may bypass the on-board controller and insert externally generated I 2 C commands by removing the jumpers on JP and JP6 and connecting the respective external and signals to the center contacts of JP and JP6. Connect to the external I 2 C host controller ground Connect to the external I 2 C host controller and. Figure 2: Connecting to External I 2 C Host Controller. 2 Skyworks Solutions, Inc. Phone [78] Fax [78] sales@skyworksinc.com B Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. August 7, 202

3 EV2 Evaluation Board for the AAT272. A Step-Up Current Regulator Driving Flash LEDs The AAT272 evaluation board is initially set up to drive two flash LEDs with a maximum 70mA current pulse. Since the AAT272 s integrated current sinks operate with independent reference circuits, they may be used separately to drive two flash LEDs or they may be combined to power a single LED with up to 00mA of current. To drive a single flash LED with A, remove either JP2 or FL2. Place the single flash LED to be driven in the FL position on the PCB. Connect the two AAT272 current sink inputs in parallel by a short jumper wire soldered between the two PCB cathode pads of FL and FL2. Remove JP2 Solder in place a jumper wire to connect FL and FL2 current sinks in parallel Figure : Connecting Current Sinks in Parallel to Drive One Flash LED at High Current Levels. AAT272 Evaluation Board User Interface Functionality The user interface is provided by four pushbuttons: MMC, ST, A/B and. A summary of operational modes for each button is outlined in Table. Definition of Each Control MMC Movie Mode Control (SW): Sets movie mode current. Each switch closure will incrementally decrease the movie mode current stating at 00% to 0% (off) in 6 steps. Refer to the AAT272 datasheet for detailed explanations of movie mode operation. ST Set Time (SW2): Generates a single flash pulse for the duration set by the IC default safety timer for the current revision of controller firmware. A/B Flash A/B select (SW): Toggles on/off each LED channel (FL, FL2, both, or Off) for movie / torch mode operation. Manual Flash Enable (SW): Initiates a flash from movie mode or an off state, then reverts back to movie mode when the AAT272 flash timeout time has been reached. The movie mode in this state may be shut off by cycling MMC to the off state, by toggling A/B to the off state or by a master system Reset (pressing SW, SW2 and SW simultaneously). Reset all data to the AAT272: Pressing and releasing SW, SW2 and SW simultaneously will reset all the registers of the AAT272 and turn off the LEDs regardless of the present operational mode. Skyworks Solutions, Inc. Phone [78] Fax [78] sales@skyworksinc.com B Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. August 7, 202

4 EV2 Evaluation Board for the AAT272. A Step-Up Current Regulator Button(s) Pushed Description [Push/Release once per step] Movie mode LED current dimming control. Each switch closure will issue an I 2 C SW (MMC) command to increment the data of the movie mode current register bits There are 6 steps in this register to step movie mode current from full scale to off (refer to the AAT272 product datasheet for additional information). SW2 (ST) [Push/Release once] Turning on the flash movie LEDs with default safety timer set by C. SW (A/B) [Push/Release once] Movie mode LED on/off control. Increments the data of the enable register bits to select FL, FL2, both or off. SW () [Push/Release once] Flash enable. Manually enables the AAT272 boost converter, initiates a single flash pulse and starts the flash timer. SW + SW [Push/Release once] Increment the data of flash to movie mode current ratio register bits, but the flash to movie mode current ratio is decreased (refer to the AAT272 product datasheet for additional information). SW + SW2 + SW [Push/Release once] Reset all registers to default. Table : User Interface Functionality (Interface Between AAT272 and the Microcontroller). VOUT R2 0k Enable JP 0 JP2 0 VCC JP L C 2.2µF µh C* 7nF U CT 2 EN AGND IN 6 SW 7 PGND AAT272 RSET FLA FLGND FLB OUT TDFN R 07k D D2 C2 2.2µF *: C may choose different values to increase or decrease the maximum flash time. Figure : AAT272 Evaluation Board Schematic. Skyworks Solutions, Inc. Phone [78] Fax [78] sales@skyworksinc.com B Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. August 7, 202

0K R6 0K R7 0K 2 U2 VDD GP GP GP PIC2F67 VSS 8 GP0 7 GP 6 GP2 C µf R 0 LED2 GRN 0 R 0 LED RED R8 0k SW R9

Figure 6: AAT272 Evaluation Board Top Layer.

5 EV2 Evaluation Board for the AAT272. A Step-Up Current Regulator DC+ DC+ JP7 MCU JP8 VCC Movie Mode Control Safety Timer A/B Control SW SW2 SW R 0K R6 0K R7 0K 2 U2 VDD GP GP GP PIC2F67 VSS 8 GP0 7 GP 6 GP2 C µf R 0 LED2 GRN 0 R 0 LED RED R8 0k SW R9 00k JP R0 0k R 0k JP JP6 Figure : AAT272 Microcontroller Section Schematic. Figure 6: AAT272 Evaluation Board Top Layer. Figure 7: AAT272 Evaluation Board Bottom Layer Skyworks Solutions, Inc. Phone [78] Fax [78] sales@skyworksinc.com B Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. August 7, 202

6 EV2 Evaluation Board for the AAT272. A Step-Up Current Regulator AAT272 Evaluation Board Bill of Materials Component Part Number Description Manufacturer U AAT272IWO.A Step-Up Current Regulator for Flash LEDs; TDFN- Package Skyworks U2 PIC2F67 8-bit CMOS, Flash-based μc; 8-pin PDIP Package Microchip SW-SW PTS6TL0 Switch Tact, SPST, mm ITT Industries R Chip Resistor 07kΩ, %, /W; 002 Vishay R9 Chip Resistor 00kΩ, %, /W; 060 Vishay R2, R-R8, R0, R Chip Resistor 0kΩ, %, /W; 060 Vishay R, R Chip Resistor 0Ω, %, /W; 060 Vishay JP, JP2, JP8 Chip Resistor 0Ω, % Vishay C, C2 GRM88R7A22KE 2.2µF, 0V, X7R, 060 Murata C GRMR7A7KA0 7nF, 0V, X7R, 002 Murata C GRM26R6A0KA0 µf, 0V, XR, 080 Murata L LQM2HPNR0MG0 Multilayer, µh,.6a, mw Murata D-D2 GMBW700A White Flash LED Sharp LED CMD-2SRC/TR8 Red LED; 206 Chicago Miniature Lamp LED2 CMD-2VGC/TR8 Green LED; 206 Chicago Miniature Lamp JP, JP, JP, JP6, JP7 PRPN0PAEN Conn. Header, 2mm Zip Sullins Electronics Table 2: AAT272 Evaluation Board Component Listing. Copyright 202 Skyworks Solutions, Inc. All Rights Reserved. Information in this document is provided in connection with Skyworks Solutions, Inc. ( Skyworks ) products or services. These materials, including the information contained herein, are provided by Skyworks as a service to its customers and may be used for informational purposes only by the customer. Skyworks assumes no responsibility for errors or omissions in these materials or the information contained herein. Skyworks may change its documentation, products, services, specifications or product descriptions at any time, without notice. Skyworks makes no commitment to update the materials or information and shall have no responsibility whatsoever for conflicts, incompatibilities, or other difficulties arising from any future changes. No license, whether express, implied, by estoppel or otherwise, is granted to any intellectual property rights by this document. Skyworks assumes no liability for any materials, products or information provided hereunder, including the sale, distribution, reproduction or use of Skyworks products, information or materials, except as may be provided in Skyworks Terms and Conditions of Sale. THE MATERIALS, PRODUCTS AND INFORMATION ARE PROVIDED AS IS WITHOUT WARRANTY OF ANY KIND, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE, INCLUDING FITNESS FOR A PARTICULAR PURPOSE OR USE, MERCHANTABILITY, PERFORMANCE, QUALITY OR NON-INFRINGEMENT OF ANY INTELLECTUAL PROPERTY RIGHT; ALL SUCH WARRANTIES ARE HEREBY EXPRESSLY DIAIMED. SKYWORKS DOES NOT WARRANT THE ACCURACY OR COMPLETENESS OF THE INFORMATION, TEXT, GRAPHICS OR OTHER ITEMS CONTAINED WITHIN THESE MATERIALS. SKYWORKS SHALL NOT BE LIABLE FOR ANY DAMAGES, IN- CLUDING BUT NOT LIMITED TO ANY SPECIAL, INDIRECT, INCIDENTAL, STATUTORY, OR CONSEQUENTIAL DAMAGES, INCLUDING WITHOUT LIMITATION, LOST REVENUES OR LOST PROFITS THAT MAY RESULT FROM THE USE OF THE MATERIALS OR INFORMATION, WHETHER OR NOT THE RECIPIENT OF MATERIALS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. Skyworks products are not intended for use in medical, lifesaving or life-sustaining applications, or other equipment in which the failure of the Skyworks products could lead to personal injury, death, physical or environmental damage. Skyworks customers using or selling Skyworks products for use in such applications do so at their own risk and agree to fully indemnify Skyworks for any damages resulting from such improper use or sale. Customers are responsible for their products and applications using Skyworks products, which may deviate from published specifications as a result of design defects, errors, or operation of products outside of published parameters or design specifications. Customers should include design and operating safeguards to minimize these and other risks. Skyworks assumes no liability for applications assistance, customer product design, or damage to any equipment resulting from the use of Skyworks products outside of stated published specifications or parameters. Skyworks, the Skyworks symbol, and Breakthrough Simplicity are trademarks or registered trademarks of Skyworks Solutions, Inc., in the United States and other countries. Third-party brands and names are for identification purposes only, and are the property of their respective owners. Additional information, including relevant terms and conditions, posted at are incorporated by reference. 6 Skyworks Solutions, Inc. Phone [78] Fax [78] sales@skyworksinc.com B Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. August 7, 202

Evaluation Board for the AAT1282 2A Driver for High Intensity LED Camera Flash

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