Texas instruments LMP91050 User Manual

Table of Contents

LMP91050 Evaluation Board

User’s Guide for the LMP91050 Evaluation Board with Sensor AFE Software

1.0. Introduction ........................................................................................................................................ 1

2.0. Equipment .......................................................................................................................................... 2

2.1. Connection Diagram .......................................................................................................................... 2

2.2. Board Assembly ................................................................................................................................. 3

3.0. Quick Start ......................................................................................................................................... 4

4.0. Powering the LMP91050SDEVAL .................................................................................................... 11

5.0. Evaluating the LMP91050 without the SPIO-4 Board. ..................................................................... 11

6.0. Installing the LMP91050 Sensor AFE Software ................................................................................ 12

7.0. Schematic ........................................................................................................................................... 13

8.0. Layout ................................................................................................................................................ 14

9.0. BOM .................................................................................................................................................. 15

1.0. Introduction

The LMP91050 Design Kit (consisting of the LMP91050 Evaluation Board, the SPIO-4 Digital Controller Board, the Sensor AFE software, and this user’s guide) is designed to ease evaluation and design-in of Texas Instrument’s LMP91050 Configurable AFE for Nondispersive In frared (NDIR).

Data capturing and evaluations are simplified by connecting the SPIO-4 Digital Controller Board (SPIO-4 board) to a PC via USB and running the Sensor AFE software. The data capture board will generate the SPI signals to communicate to and capture data from the LMP91050. The user will also have the option to evaluate the LMP91050 without using the SPIO-4 board or the Sensor AFE software.

The on board data converter will digitize the LMP91050’s analog output, and the software will display these results in time domain and histogram. The software also allows customers to write to and read from registers, to configure the device’s gain, output offset, and common mode voltage, and most importantly, to configure and learn about the LMP91050.

This document describes the connection between the boards and PC, and provides a quick start for voltage measurements. This document also describes how to evaluate the LMP91050 with and without the SPIO-4 board and provides the schematic, board layout, and BOM.

2.0. Equipment

1. LMP91050 evaluation board (NSID: LMP91050SDEVAL)

2. SPIO-4 digital controller board (NSID: SPIO-4)

3. Power supplies (optional) to source VDD-EXT or IN_DUT.

4. Multimeter

5. PC with Sensor AFE software

6. NDIR Thermopile Sensor (optional)

2.1. Connection Diagram

Figure 1 shows the connection between the LMP91050 Evaluation Board (LMP91050SDEVAL), SPIO-4 board, and a personal computer with the LMP91050 Sensor AFE software. LMP91050 can be powered using external power supplies or from the SPIO-4 board.

LMP91050 Evaluation Board

Figure 1 – Connection Diagram

2.2. Board Assembly

LMP91050 Evaluation Board

Figure 2 – LMP91050 Evaluation Board Assembly

LMP91050 Evaluation Board

3.0. Quick Start

The following procedures show a quick method to assemble the LMP91050SDEVAL and perform a quick voltage reading.

A. LMP91050 EVB Jumper Connections

1. The jumpers for this example application can be seen in Figure 3 and Table 1

2. The SPIO-4 board is properly setup out of the box (no assembly required).

3. The schematic for the LMP91050SDEVAL can be seen in Figure 10.

Figure 3 – Jumper Settings (Default) for voltage reading

Jumpers

Purpose

JP1: VDD_DUT

P1-P2

Connect LMP91050 VDD to +3.3V from SPIO4

JP2: VREF_ADC

P1-P2

Connect ADC VREF to 4.1V from U5 (LM4140)

JP3: VA_ADC

P1-P2

Connect ADC VA to +5V from SPIO4

JP4: OUT_DUT to ADC

P1-P2

Connect LMP91050 OUT to ADC input RC filter

J2: IN to CMOUT

Open

Connect LMP91050 IN to CMOUT. Note: Bo ard is

short IN to CMOUT for easy evaluation.

provided with this jumper open. Use provided jumper to

Table 1 - Jumpers for Voltage Measurement

B. Installing/Opening the Software - follow section 6.0 to install and open the LMP91050 Sensor

AFE software.

C. Connecting and Powering the Boards – these steps have to be done in this order.

1. Connect the LMP91050SDEVAL’s J1 to SPIO-4 Board’s J6. See Figure 4.

LMP91050 Evaluation Board

Figure 4 – LMP91050SDEVAL-to-SPIO-4 Board Connection

2. Connect SPIO-4 board to a PC via USB.

3. Use a multimeter to measure LMP91050SDEVAL’s +5V test point; it should be

approximately 5V. If it is not, check your power supplies and jumpers. Measure test point VREF_ADC; it should be approximately 4.1V. If it’s not, check your jumpers and U5.

1 2 3 4 5

LMP91050 Evaluation Board

D. Sensor AFE Software Overview

Once connection between the boards and PC is established, you can use the software to com m unicate to and capture data from the LMP91050. Drag cursor over window icons to get an icon description. Some items of interest are shown in Figure 5.

Figure 5 – Sensor AFE Items of Interest

1. Menu Bar Icons (from left to right) a. Save Configuration to File: Saves the current configuration settings (register

settings) to an .xml file.

b. Load Configuration File: Loads the selected configuration settings (register

settings) .xml file.

c. Register Map: Opens Register Map window. An alternative to the Virtual

Device, for writing and reading the device registers. See datasheet for details on device Register Map.

d. Save All Registers to File: Saves register contents to a .cvs file. e. Read All Register from Board: After configuring the register map, use this button

to read all registers. Functional only in SDIO Mode (see Item 3).

f. Write All Registers To Board: After configuring the register map use this button

to write all registers. Registers will not be updated until this step is done.

g. Zoo m In/Out Diagram Ima g e: Zoom in and out of the virtual device image. h. Show Tutorial: Takes you to the interactive Software Overview videos. i. Documentation: Accesses the LMP91050 Datasheet, SPIO4 User’s Guide, or

Evaluation Board User’s Guide.

2. User Inputs