DS1870 LDMOS BIAS CONTROLLER EV KIT

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1 GENERAL DESCRIPTION The DS1870 EV Kit provides hardware and Window s compatible software to simplify the evaluation of the DS1870 LDMOS Bias Controller. FEATURES Includes test socket for solderless connectivity during evaluation Test points and headers are provided for connection to external circuitry and test equipment Windows compatible software Software can in-circuit program DS1870 s for in-depth evaluations Software supports programming DS1870 s from a configuration file for fast and consistent programming. KIT CONTENTS DS1870 EV Board DS3900 Communications Module Software on a 3.5 floppy disk Instructions EQUIPMENT REQUIRED PC with Windows OS (Win95/Win 4.0 or later) 9-pin Serial cable (See Table 1) 5V power supply Table 1 - Serial Cable Vendors Vendor Radio Shack radioshack.com & local stores DigiKey digikey.com AE1020-ND Part Number GETTING STARTED 1. Copy the executable file (DS1870K.exe) from the floppy disk to the PC s hard drive. 2. Install the DS3900 on the board as shown in Figure Ensure the DS3900 s switches are pushed to the side labeled ON CTS. 4. Connect the serial cable from the PC to the DS Check to see if all the address jumpers are on the GND side. If they are not, the default software I 2 C address will have to be changed to communicate with the part (See 2-Wire Page). 6. Connect the 5.0V power supply to the EV board. 7. Start the DS1870K application software 8. See the Using the Software section for more detail on software operation. HARDWARE USE The DS1870K hardware was designed with 2 primary functions in mind. The first is to provide easy connectivity to the DS1870 IC that comes in a small TSSOP package. The second objective is to make the evaluation kit so it is easy to use as an in-circuit programming board. This allows DS1870's to be programmed and tested in typical application circuits. 01/30/04

2 Using the PCB for Evaluating the DS1870K The EV board comes with a TSSOP socket to allow multiple DS1870s to be tested/programmed quickly, a DS3900 communications module for communicating with the DS1870 from a PC, supply decoupling capacitors, power connectors, and header connectors and testpoints for connecting the device to external circuitry and test equipment. Additionally, the fault output has a 4.7kΩ pull-up resistor to facilitate high logic level outputs since that pin is an open collector output. The I 2 C address inputs (A2, A1, A0) have jumpers that allow the 2-wire address to be modified if required. They should initially be jumpered to GND so the DS1870's I 2 C slave address will match the software's default value of A0h. In addition to the basics, several resistor and capacitor footprints have been provided on the bottom of the PCB for connecting external resistors and capacitors to the potentiometers to modify the output voltage range of the DS1870. See the schematic in Appendix A for details. Figure 1. DS1870 Evaluation Kit Hardware Using the PCB for in-circuit Programming DS1870's The DS1870K Evaluation Kit can be used to in-circuit program devices for evaluating the DS1870 in a typical application. To do this, the in-circuit DS1870 must have its own pull-ups on the application board to prevent SDA and SCL from floating during normal operation. Connect the SDA and SCL testpoints on the evaluation PCB to the SDA and SCL connections available on the application board. The kit PCB should be powered to the same voltage level as the application board and the two boards should share a common ground connection. Ensure no devices are installed in the kit board's sockets because they may cause a 2-wire addressing conflict if present. When the software is started it should be able to program the DS1870 exactly as it would if the device was in the kit's test socket. See Figure 2 for the hardware connections and the software section for information related to using the software. 01/30/04 2 of 9

3 Figure 2. In-circuit Programming with the Evaluation Kit Software USING THE SOFTWARE The DS1870 software is composed of 5-tabbed pages of functions called the General, Manual Pot Control, Memory, 2-Wire, and File pages. The following sections describe each page s functions. General Page The General Page (see Figure 3) is the first tab of the software. It includes the ability to read all the status and ADC registers of the DS1870 with a single click. It can also continuously read the DS1870 status/adc registers and write the DS1870 s write protection Password Entry byte (PWE). The Read Once button reads all the ADC register values and displays them in the Value (hex) section. It then multiplies each digital value by the Weight parameter, and displays the value in volts. The default weights shown work for the factory calibrated ADC gain and offset values. If device is calibrated with a different gain than the default, the user can compensate by adjusting the weight value. Although the DS1870 can also modify the result's offset, the software does provide any support for that feature. For non-zero offsets the voltage value displayed will be incorrect. The user will have to refer to the hexadecimal values and calculate what that means in terms of volts or their real world units. In addition to the ADC values, the status registers and potentiometer positions are read to provide a good summary of the parts current state. The Read Continuous button performs all of the Read Once button's functions with a 3Hz refresh rate. This allows the user to continuously monitor the state of the DS1870 without having to continuously click the Read Once button. This mode is exited by clicking the Stop button (same button as Read Continuous) or by exiting the general page. The Write PWE button writes the password value in the edit box to the PWE register. This is provided on the general page to make it easy for users to disable the write protection circuitry before they begin adjusting registers with subsequent functions of the software. The read buttons on the general page of the software do not require write access, so they do not require the password to be entered for proper operation. The I 2 C Address box displays the software's current I 2 C address setting. This setting must match the address set by the DS1870's address pin states to establish communication. This setting can be changed using the change button on the 2-wire page. 01/30/04 3 of 9

4 Figure 3. The General Page Manual Potentiometer Control Page The Manual Pot Control Page (see Figure 4) is used to enable or disable the potentiometer s automated LUT control sequence. Once the automated control sequence has been disabled, the manual control page can be used to force the base and offset values of each potentiometer to a particular value for evaluation, or it can be used to force the table indexes to a particular value to test the indexing functionality. Figure 4. The Manual Pot Control Page 01/30/04 4 of 9

5 The B/O_en bit, shown as a check box at the top of the Manual Pot Control page, is used to enable or disable the part's ability to update the potentiometer's base and offset values from the LUT values. The Index_en bit enable/disables the DS1870's ability to determine the index byte values from the ADC results. On power-up, the DS1870 will have both of these bits set, which enables the device to function in its normal automated mode. Because the part will automatically write over the values written to the potentiometer with values determined by the LUTs and the current ADC values, the software prevents writing to these registers. Once a check box is unchecked, the software allows the corresponding registers to be manually controlled. This can be used to force the potentiometer to a particular value, or to check that the indexing is working as expected. Each time the Manual Pot Control page is entered the software will read the Man DAC register and update the B/O_en and the Index_en bits on the screen to ensure they are accurately represented. Memory Page The Memory Page (see Figure 5) can be used to read and write the DS1870 s registers to configure and test the device. It provides three different ways of reading and four different ways to write to the device, each being very useful in its own way. This page is very easy to use because it handles all the start and stop conditions, device addressing, and acknowledgement required for the communicating as specified in the datasheet. The device address used by default is A0h, but this can be changed to match the current device s address on the 2-wire page if it is not equal to the default value. In addition to the general read and write tools, the table select byte has its own section with its memory address (7Fh) pre-coded because of the frequency of its modification and verification. Figure 5. The Memory Page The Table Select Byte (TSB) section allows the user to read or write the TSB with a single click. Data in the table select edit box is written to address 7Fh whenever the Write button in this section is clicked. When the TSB Read button is clicked, the device s TSB is read from address 7Fh, and the table select edit box is updated to reflect the present value in the device s register. To help ensure the software and the user are both aware of the devices present TSB value, the TSB is read from the part each time the Memory page is accessed to ensure the TSB displayed by the software matches the device s current status. The TSB can be written to a new value by simply typing the new value and pressing enter. The Single and Two byte write tools allow one or two bytes of data to be written to or read from the device at the user s specified memory address (ADDR) with a single click. To write byte(s), type both the address and data into their designated edit boxes in hexadecimal and click the corresponding Write button or press enter. To read byte(s), type in the memory address and click the corresponding Read button. Two byte I 2 C reads and writes are performed most significant byte (MSB) first, which is the lower of the 01/30/04 5 of 9

6 two memory addresses. So when a two byte read is performed at address 00h, the data at memory location 00h would be the MSB, and the data at memory location 01h would be the LSB. The Memory Row Read and Write buttons are used to read and write whole 8-byte pages of memory. The row# is the hexadecimal memory address of the first byte in the row that will be read or modified. Memory page reads and writes are always done on modulus 8 memory boundaries to ensure writes to not cross page boundaries. Because of this, the second nibble of the row# s address will always be either zero or eight. Failure to enter a proper row# will generate an error. The Memory Fill Tool can be used to fill an entire range of memory with the same data. The memory between the starting and stopping memory addresses will be written to the new data value. This is particularly useful when the need arises to fill an entire LUT to a constant value to ensure that the potentiometer values will not change position when the part is in automated mode. 2-Wire Page The 2-wire page (see Figure 6) is used to change the 2-wire device address, and as a flexible tool to communicate with any 2-wire device. Clicking on a 2-wire control immediately performs the corresponding function. A list of 2-wire functions is shown in Table 2. The 2-wire page's status box tracks all of the actions that have been recently performed. The status box automatically scrolls to allow the user to see an entire transaction. Figure 6. The 2-Wire Page 01/30/04 6 of 9

7 Table 2. 2-Wire Page Function Descriptions Function Send Start Send Write Send Read Send Byte Read w/ack Read w/nack Send Stop Reset Find Change Description Performs I 2 C start and repeated start functions. Writes the device address (R/W=0) listed in the Software I2C Address section over the I 2 C bus. Writes the device address (R/W=1) listed in the Software I2C Address section over the I 2 C bus. Sends the hexadecimal byte in the edit box located immediately to the right of the send byte button over the I 2 C bus. Three send byte buttons are provided for the user's convenience. Reads one byte and acknowledges (ACK) the data transfer. Reads one byte and does not acknowledge (NACK) the data transfer. Performs I 2 C stop condition. This function clocks the bus 9-times and sends a stop condition. In the event that the I 2 C bus appears to become non-responsive, the reset I 2 C bus function returns control of the bus to the user. The find button searches for all the I 2 C devices present on the I 2 C bus and lists their addresses. This can be used to determine the address of an I 2 C device if it has been modified from its default value. The Change button is used to change the I 2 C Slave address the software uses during communications. Values entered into its edit box should be even values equivalent to the slave address byte when the read/write bit is zero (R/W=0). The software automatically writes the slave address byte with R/W=1 for read operations. This address is used by all software functions that communicate on the I 2 C bus. To access a device using the 2-wire page, the user must manually instruct the DS3900 to perform the 2-wire functions in the proper sequence. A DS1870 example is shown below. Example: Write the table select byte (memory address 7Fh) of a DS1870 (device address A2h) to 01h. The user must: 1) Change the device address to A2h (A0h, software default). 2) Send start (issues a 2-wire start condition). 3) Send write (writes A2h, the device address, over the 2-wire bus). 4) Send data 7Fh (writes 7F, the memory address of the Table Select Byte). 5) Send data 01h (writes 01h, the data, to the Table Select Byte). 6) Send stop (issues a 2-wire stop condition). File Page The file page (see Figure 7) can be used to read all the DS1870 s registers and dump them to file, as well as to program the DS1870 from a text file. To Dump the DS1870 s current settings to a file, select the tables that are desired to be saved to the file and click the Dump button. The software will read every byte address in the selected tables, including bytes that are not implemented, and output the data to a comma separated values (.csv) text file that can be read and modified using Microsoft's Excel. To Program from a file, first create a template by dumping the memory tables you wish to program to a csv file. Modify any bytes that you wish using Excel and then resave the file. Be sure to save the document as a.csv file when your modifications are complete. Finally click the Program button and select the file you wish programmed into the part. Valid modifications to the dump file before programming differ depending on the tables you are programming. The lower memory and Table 1 are programmed one byte at a time, and hence you can program them in any order, and it is ok to delete values that you do not wish to be modified (such as the calibration data in Table 1). Tables 2-5 are programmed one memory row at a time, and they require the entire LUT to be programmed. Missing LUT values will result in an error. You can however delete an entire LUT to prevent it from being programmed. Dump files will contain bytes that are not implemented in the DS1870, but the unimplemented bytes do not effect programming. These bytes do not have to be removed before programming, but they can be removed without any consequence. 01/30/04 7 of 9

8 Figure 7. The File Page All values past the second comma (column in Excel) are considered as comments by the software, so feel free to place comments into your files to help keep track of revisions, register names, or critical parameters. TROUBLESHOOTING This section offers suggestions for correcting common user problems with evaluation kits. Help beyond these suggestions can be obtained by or by calling our technical support group at Table 2. Troubleshooting Guide Symptom Cause Solution "EV Kit not found" error message Communication errors Not able to write to EEPROM Board not properly connected No device in socket 2-wire device address mismatch DS3900 switches Off Device in socket backward Board not properly connected Correct password not yet entered with software. Ensure the serial cable is connected between the PC and DS3900. Verify the DS3900 is firmly in place on the PCB. Verify the power is on. When the evaluation board is not found the software must be shutdown and restarted after the board is properly connected before it can be used. Verify the device is in the test socket and aligned with the test socket's spring-loaded lead attachment points. Verify the device address on the 2-wire page matches the device's slave address. The Find button on the 2-wire page can be used to verify the device's slave address. Turn the DS3900 switches on. Ensure the pin 1 indicator of the device is oriented towards the top left of the socket. See Figure 1 for orientation. Occasionally kit board setup may be disturbed after the board is initially powered up. Re-verify board connections. Using the password entry button on the General page to enter the password so it matches the values written to Table 1 bytes 80h & 81h. 01/30/04 8 of 9

9 APPENDIX 1 - DS1870 EVALUATION KIT SCHEMATIC 01/30/04 9 of 9