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In the “Security” pop-up window, under the “Security Level” tab select either “Low” or “Medium”. Click on “OK”
in the “Security” pop-up window and also on “OK” in the “Options” pop-up window.
2.0 Description
The PGA309EVM key hardware consists of two boards (see Figure 1), PGA309 Sensor Interface Board and
PGA309 PC Interface Board. The PGA309 Sensor Interface Board contains the PGA309, external SOT23-5
EEPROM, and several jumpers for ease of bridge sensor configuration. The PGA309 PC Interface Board
contains an RS-232 serial interface, a 3V/5V programmable linear regulator, a switch for power control to the
PGA309 Sensor Interface Board, both One-Wire and Two-Wire interface configuration and control logic, and
an A/D Converter (ADS1100).
The PGA309EVM is designed to allow the user to attach his sensor to the PGA309 Sensor Interface Board
and place this combination in a temperature chamber. By controlling the applied pressure to the pressure
sensor and the temperature of the temperature chamber, the Sensor combination can be calibrated
for optimum end module accuracy. The PGA309 Sensor Interface Board is rated for operation from -40°C to
+125°C. Power, ground, output and digital interface wires connect the PGA309 Sensor Interface Board in the
temperature chamber to the external PGA309 PC Interface Board. The PGA309 PC Interface Board
communicates to a test computer through a standard RS-232 serial port via the PGA309EVM PC Cable. For
USA shipments an AC wall adapter is included to provide 6Vdc to the PGA309 PC Interface Board. For all
other applications an alternate connection on the PGA309 PC Interface Board is provided for connection to a
6Vdc (6Vdc-9Vdc) lab supply. The on-board A/D Converter, ADS1100, on the PGA309 PC Interface Board
allows for easy reading of the analog output of the PGA309.
The PGA309EVM Software is comprised of two parts. The Board Control Software contains all of the interface
and control for communication to the PGA309 through the PGA309 PC Interface Board. It allows for reading
and writing to all registers in the PGA309 as well as reading and writing to the external SOT23-5 EEPROM.
Both Two-Wire and One-Wire communication options are available. In addition configuration of the PGA309
PC Interface Board and readback of the ADS1100 is provided. The PGA309 Calibration Spreadsheet for
Microsoft® Excel provides a useful tool to calculate optimum temperature coefficients for the
Sensor calibration based on real-world measurements of pressures at different temperatures. The PGA309
Calibration Spreadsheet also contains Visual Basic for Applications code that allows its integration with the
Board Control Software. These macros allow the user to exchange PGA309 settings between the program
and the spreadsheet and save the resulting EEPROM configuration file.
