Datasheet

6 LMP91051EVM User’s Guide snou034
i. Documentation: Accesses the LMP91051 Datasheet, SPIO4 User’s Guide, or
Evaluation Board User’s Guide.
2. Device Selection and User Inputs
a. LMP91050/1 : Toggle between LMP91050 and LMP91051 device.
b. fc: Center frequency of external bandpass filter.
c. bandwidth: Pass band bandwidth of external bandpass filter.
d. R1_EXT, R2_EXT, C1_EXT, C2_EXT: External bandpass filter component values
calculated based on user input for center frequency (fc) and pass band (bandwidth)
described above.
e. Supply: LMP91051 supply voltage (VDD).
f. IC Temp: LMP91051 operating temperature
g. Offset Adjust Voltage: The tool will calculate the DAC code (decimal) required to
achieve this output offset adjust voltage. User must then Write to the register to update
the value in the NDAC register.
h. ADC Vref: ADC reference voltage. User should input value measured at VREF_ADC
test point. Value used to calculate displayed Output Voltage.
i. Vout Dark: This value corresponds to the user measured value at the LMP91051
output (OUT) when input is shorted (IN = CMOUT). Tool will use this value to estimate
LMP91051 input voltage (IN - CMOUT) on subsequent measurements.
3. Change Mode: Change between device Read Mode OFF (default) and ON. See datasheet for
details on SPI Read Mode.
4. Eval Board Setting: Document to show user how to configure jumpers and connect thermopile
based on sensor selected.
5. Virtual Device: Drag cursor across color coded blocks and click to configure each block. To
update registers “Write All Registers” when done.
3.2. Configuring the LMP91051 Using the Sensor AFE Software
Follow the step-by-step instructions under the “HelpBar” mini-tab (left hand side of the GUI) to configure the
LMP91051 for this example. These step-by-step instructions are discussed in details below, and the
recommended configuration should look similar to Figure 5.