Texas Instruments ADC161S626BEB User Manual

User’s Guide

SNAU120-April 2012

ADC161S626BEB User’s Guide

LIST OF FIGURES ............................................................................................................. 1

LIST OF TABLES ............................................................................................................... 1

1. INTRODUCTION ......................................................................................................... 1

2. BOARD ASSEMBLY ................................................................................................... 1

3. QUICK START ............................................................................................................ 3

4. FUNCTIONAL DESCRIPTION .................................................................................... 4

5. HARDWARE SCHEMATIC ......................................................................................... 5

6. ADC161S626 EVALU ATIO N BOARD BILL OF MATERIALS ................................... 6

EVALUATION BOARD/KIT/MODULE (EVM).................................................................. 11

LIST OF FIGURES

Figure 1: ADC161S626 Eval board connected to SPIO board. ..................................... 3

LIST OF TABLES

Table 1: Test Points on the ADC161S626 Evaluation Board ........................................ 2

Table 2: Connectors on the ADC161S626 E valuation Board ....................................... 2

Table 3: Jumpers .............................................................................................................. 2

1. Introduction

The ADC161S626BEB Evaluation Board Design Kit (consisting of the ADC161S626BEB board, this users
guide, an optional SPIO4 board and an optional sensor board) is intended to ease evaluation of the
ADC161S626. With the optional SPIO4 board and optional Sensor board, the board allows evaluation of an
entire Sensor AFE system.
The evaluation board can be used in stand alone mode, in which the user interfaces with the part through the
SPIO-GPSI16 connector and applies input signals on the AB12 connector. The board can also be used with
an SPIO4 board in place of an external pattern generator. Finally, in the Sensor AFE system, the
ADC161S626BEB board and the optional sensor board (for example, the LMP91000 Configurable AFE Gas
Sensor board) can be used with an SPIO4 board to evaluate the entire Sensor AFE system.

2. Board Assembly

The ADC161S626BEB evaluation board comes fully assembled and ready for use. Refer to the Bill of
Materials for a description of components and to the schematic at the end of this document. There are
jumper selections for choosing between different power supply and clock configurations.

SNAU120-April 2012 ADC161S626BEB User’s Guide 1

Test Point

Purpose

SCLK,
DOUT, CSB

ADC SPI bus signals. Located below the DUT.

VREF,

If external supplies on the banana jacks are used for VREF, VA,

used, the banana jacks can be used as test points.

Connector

Purpose

SPIO­GPSI16

16 pin dual row right angle male header to connect to the SPIO4
board.

GPSI16

16 pin dual row right angle female header. Carries signals from
the SPIO4 board to any optional SensorAFE board.

AB12

12 pin dual row right angle male header. Carries analog bus
to the ADC.

Jumper

Purpose

VREF
SELECT

Selects reference source for VREF. Settings are Vref banana
jack, on board Va or on board LM4120-4.1

VIO SELECT

Allows choice of VIO for the chip, the SPIO interface and

banana jack.

5V from the SPIO connector.

Board Assembly

VDDIO, VA

Table 1: Test Points on the ADC161S626 Evaluation Board

Table 2: Connectors on the ADC161S626 Evaluation Board

VA SELECT Allows choice of VA for the part. Choices are VA banana jack or

VIO EXT the center pins of jumpers VREF SELECT, VIO
SELECT, VA SELECT can be used as a test point for those
signals. If on board power supplies (from the SPIO board) are

signals from an external source or the optional Sensor AFE board

whatever sensor board is connected to the ADC board. Choices
are on board Va, 3.3V from the SPIO connector or the VIO EXT

Table 3: Jumpers

2 ADC161S626BEB User’s Guide SNAU120-April 2012

3. Quick Start

The fastest way to s tart usi ng the ADC 161S626 evaluatio n board is to use it with the SPIO 4 board, a senso r
board such as the LMP91000 and the Sensor AFE software.

3.1 Sensor AFE Setup (LMP91000)

• Install the VA SELEC T jumper between pins 1 and 2 (VA and 5V) . This will power VA from the 5V
supply coming from the SPIO4 board.

• Install the VIO SELECT j um per between pi ns 2 and 3 (VA and VDDIO ) . T his will po wer the IO on t he
chip from the same voltage as VA or 5V. Note, this VDDIO will go on to the LMP91000 board.

• Install the VREF SELECT j umper from pin 2 to 3 (VREF and ON BOAR D REF) . This will connect the
ADC VREF line to the 4.096V on board LM4120 reference.

• Ensure that a 4MHz c r ystal is installed in the socket Y2 an d th at th ere is no s igna l ap pl ied at t he CLK
IN BNC jack.

• Connect the SPIO4 board t o the A DC 1 61 S62 6B EB bo ar d at th e S PI O-G SPI 16 m ale h ead er. Li ne u p
the white arrows on the bottom of the headers.

• Connect the LMP91 000 board to the GPSI16 and AB12 headers. Line up the white arrows at the
bottom of the headers (see Figure 1)

• Connect the SPIO4 board to its power supply and to your computer via the USB cable in that order.

Figure 1: ADC161S626 Eval board connected to SPIO board.

• Start the SensorAFE software on your computer.

3.2 Setup for Other Boards

• Choose the VA supply:

o Install the VA SELECT jum per between pins 1 and 2 (VA and 5V) to power VA f rom the 5V

supply coming from the SPIO4 or SPUSI2 board.

SNAU120-April 2012 ADC161S626BEB User’s Guide 3

o Leave the jumper off to select the VA banana jack

• Choose the VDDIO supply:

o Install the VIO SELECT jumper between pins 1 and 2 (+3.3V and VDDIO) to choose the 3.3V

supply coming from the SPIO4 or SPUSI2 board.

o Install the VIO SELECT jumper between pins 2 and 3 (VA and VDDIO) to choose the IO on

the chip from the same voltage as VA or 5V.

o Leave the jumper off to select the VIO EXT banana jack.

• Choose the VREF supply:

o Install the VREF SELECT jumper from pin 1 to pin 2 (VA and ON BOAR D REF) to connect

the VREF pin to the VA supply.

o Install the VREF SELECT jumper from pin 2 to 3 (VREF and ON BO ARD REF) to connect

the ADC VREF line to the 4.096V on board LM4120 reference.

o Leave the jumper off to select the external reference present on the VREF banana jack.

• Choose the clock source

o Install a 4MHz crystal in the socket Y2 to generate an on board clock that can go to the

SPIO4 board.

o Leave Y2 unpopulated an d att ach a 4 MHz signal to the CLK IN BNC con nec tor to generate a

clock for the SPIO4 board.

o Bring a clock to the SPIO-GPSI16 header from an external board of your choice.

4. Functional Description

4.1 ADC Reference Circuitry

This evaluation board includes three options to source the voltage reference, VREF. The options are
selecting the fixed, on bo ard +4.096V voltag e reference (LM4 120-4.1) to source VREF, connectin g VREF to
VA of the device, or using the ex ternal banana jack to sourc e VREF. To select the +4.1V referenc e, short
pins 2 & 3 of VREF SELECT jumper. To connect VA to VREF, short pins 1 and 2 of the VREF SELECT
jumper. To select the exter nal reference, do not ins tall a jumper. Consult th e data sheet for the accept able
values of VREF.

4.2 SPI Interface

The ADC161S626 requ ires three SPI pins. T he input pins are Serial C lock (SCLK), Chip Select Bar (CSB).
The output pin is data o ut or Master In Slave Out (MISO). T he user must provide input signals for SCLK,
CSB.

4.2.1 Serial Clock (SCLK, CSB, MISO, MOSI)

These signals can be provided b y the SPIO 4 or SPUS I2 board. I n stand a lone mode, t hese signa ls mus t be
provided by the user on the SPIO-GPSI16 header. The signal lev els are TTL and CMOS compatible. The
voltage expected is set by the value of VDDIO that is applied to the board.

4 ADC161S626BEB User’s Guide SNAU120-April 2012