LMP90100EB/NOPB National Semiconductor, LMP90100EB/NOPB Datasheet - Page 5

• Manufacturer Part Number: LMP90100EB/NOPB
• Description: EVAL BOARD FOR LMP90100
• Manufacturer: National Semiconductor

Specifications of LMP90100EB/NOPB

• Main Purpose: Interface, Analog Front End (AFE)
• Embedded: No
• Utilized Ic / Part: LMP90100
• Primary Attributes: 8 Programmable Output Data Rates Per Channel
• Secondary Attributes: SPI Interface
• Silicon Manufacturer: National
• Silicon Core Number: LMP90100
• Kit Application Type: Data Converter
• Application Sub Type: ADC
• Kit Contents: LMP90100 Evaluation Board
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

© 2009 National Semiconductor Corporation
E. Configuring the Device Using the Sensor AFE Software
5.
6.
1.
Connect SPIO-4 Board to a PC via USB.
Use a multimeter to measure LMP90100EB’s JP6, JP7; they should all be approximately 5V. If they are
not, check your power supplies and jumpers. Measure JP14.P2; it should be approximately 4.1V. If
it’s not, check your jumpers and U4.
Follow the step-by-step instructions under the “HelpBar” mini-tab (left hand side of the GUI) to
configure the device. The recommended configuration is shown in Figure 4.
a.
b.
c.
d.
e.
f.
g.
h.
i.
Step 1: Select a Sensor - select “DC”  “DC” since the input source is not a sensor.
Step 2: Configure Inputs – click on the “INPUT MUX” block to set “VINP = 000: VIN0” and
“VINN = 001: VIN1”. Since VIN0 = (3/4) VREF1 and VIN1 = (1/4) VREF1, the measurement
across this channel will be (1/2) VREF1.
Step 3: Select Reference – click on the “VREF MUX” block to choose “VREF_SEL = 0: VREF1”.
Make sure the VREF1 value is 4.1V.
Step 4: Source IB1/IB2? – this step can be ignored because neither IB1 nor IB2 is connected to the
inputs.
Step 5: Set Gain – since VIN = (1/2) VREF1, the maximum gain that can be set is 2. Click on the
“FGA” block, “PGA” block, or the “Gain” slider to select the gain.
Step 6: Set Buffer – click on the “BUFF” block to include or exclude the buffer from the signal path.
Step 7: Set Calibration - click on the “No Calibration” block to enable or disable calibration. Refer
to the LMP90100 datasheet to more information on the LMP90100’s background calibration types
and modes.
Step 8: Int/Ext CLK? – click on the “CLK MUX” block and make sure the internal clock is selected.
Step 9: Performance - click on the “Performance” mini-tab. This tab displays the Estimated
Device Performance base on the block diagram that you’ve configured, as well as the Measured
System Performance if you’ve connected a board and ran the LMP90100.
Page 5 of 30
with Sensor AFE Software User’s Guide
lmp90100eb_usersguide_20101227_v23.doc
LMP90100 Evaluation Board