Texas instruments LMP91200 User Manual

LMP91200 Evaluation Board User Guide

Jumper name

Configuration

Description

the three

1-3

Reference resistor = 100ohm, when a Pt100 is connected to the board

3-5

Reference resistor = 1000ohm, when a Pt1000 is connected to the board

4-6 shorted

External reference resistor

Rev 0.5

LMP91200 Evaluati on Boa rd User Guide

The LMP91200 evalboard (LMP91200EVAL) can be used as stand-alone or as part of SensorAFE eval platform (refer to SensorAFE platform for software and required hardware). It allows configuring the LMP91200 through a 3-wire SPI interface and testing the device with real PH probe. Moreover the eval board allows the connection of external RTD (for instance Pt100, Pt1000).

http://www.national.com/en/industrial/sensing/sensor_afe/tools.html

(551600628-001 RevB)

Figure 1 LMP91200EVAL

1. PH probe and RTD connection

The LMP91200 evalboard is not provided with any PH probe and RTD.

The PH probe can be connected to the BNC connector labeled PH_SENSOR. The footprint of PH_SENSOR allows the connection of a Triaxial BNC. So in case of need replace the BNC soldered on the eval board with a triaxial BNC (refer to Schematic section to check the pinout of the Triaxial BNC).

The external RTD can be connected to the RTD_IN connector. The eval board is already provided with two reference resistors labeled R_CAL_100 and R_CAL_1000, but in case of need an external reference resistor can be connected to the T_CAL_EXT connector.

After the connection of the RTD, configure the JP6 according to the table below

Select

JP6

one of

options

shorted