INA826EVM

Thisuser'sguidedescribesthecharacteristics,operation,anduseof theevaluationmodule(EVM) for the INA826.TheEVMisdesignedtoevaluatetheperformanceof thedevice inbothsingleanddual-supply configurations. Thisdocument also includes theschematic, printedcircuit board (PCB) layouts, anda complete bill of materials (BOM). Throughout this document the terms evaluation board, evaluation module,andEVMaresynonymouswiththeINA826EVM.

1 Introduction and Overview

1.1 INA826

The INA826 is a low-power, wide-supply voltage instrumentation amplifier that can operate in both single and dual supply configurations. A single external resistor sets the gain from 1 to 1000. The input voltage range extends from the negative power supply to 1.0 V below the positive power supply. The rail-to-rail output allows for use in low-voltage applications. The device operates with a supply voltage between 2.7 V nd 36 V and draws a maximum quiescent current of 250 µA. The device is available in MSOP-8, SO-8,and DFN-8 packages.

1.2 INA826EVM

The INA826EVM is intended to provide basic functional evaluation of the INA826. It provides the following features:

• Intuitive evaluation with the silkscreen schematic

• Easy access to nodes with surface-mount test points

• Advanced evaluation with two prototype areas

• Reference voltage source flexibility

• Convenient input and output filtering

The schematic and component sides of the EVM are shown in Figure 1 and Figure 2, respectively.

2 Quick Start

The procedures presented in this section describe how to quickly set up and use the INA826EVM for

evaluation in dual-supply and single-supply configurations.

2.1 Dual Supply

Make the following connections to set up the INA826EVM for dual-supply operation.

1. +15 V to V+ test point

2.–15 V to V– test point

3. Ground to REF test point or install a 0 Ω resistor as R5

4. Differential input (for example, a 1-VPP

sine wave) to V–IN and V+IN test points

5. Oscilloscope to VO test point

Ensure that R1 = R2 = RO = 0 Ω and that RG and CO are not populated. Figure 3 depicts a proper dual supply configuration.

2.2 Single Supply

Make the following connections to set up the INA826EVM for single-supply operation with a direct

connection for the reference voltage.

1. +5 V to V+ test point

2. GND to V– test point

3. +2.5 V to REF test point

4. Differential input (for example, a 1-VPP

sine wave) to V–IN and V+IN test points

5. Oscilloscope to VO test point

Ensure that R1 = R2 = RO = 0 Ω and that RG , R5, and CO are not populated. Figure 4 depicts a proper

single-supply configuration with a direct REF connection.

MakethefollowingconnectionstosetuptheINA826EVMforsingle-supplyoperationwithabuffered referencevoltage.ThisexampleusesanOPA376asthebufferoperationalamplifier.Dependingonthe application,alternatesingle-supplybufferoperationalamplifiersincludetheOPA330andOPA378.The OPA277isagoodchoiceforhigh-voltageapplications.Thebufferedconfigurationisusefulwhenthe sourceimpedanceishigh(forexample,avoltagedivider).Bufferingahigh-impedancesourcewithan operationalamplifierprovidesalow-impedancesource,whichpreservescommon-moderejection.

1. +5VtoV+andOAV+testpoints

2. GNDtoV–andOAV–testpoints

3. +2.5VtoOAVIN+testpoint

4. PopulateR3witha0-Ωresistor

5. PopulateC4,C5,C11,andC12withbypasscapacitors

6. Differential input(forexample,a1-VPP

sinewave)toV–INandV+INtestpoints

7. OscilloscopetoVOtestpoint

EnsurethatR1=R2=RO=0ΩandthatRG,CO,R4,andR5arenotpopulated.Figure5depictsa properdual-supplyconfigurationwithabufferedREFvoltage.