O W Y.C 0 0 1 M.T . O W C . W WW .100Y M.T O W WW .100Y.C M.TW .TW M WW 00Y.CO .TW .CO .TW Y W 0 0 M .1 W.1 Y.COM W WW 00Y.CO .TW W W W .T 00 W.1 Y.COM W W.1 Y.COM W W W W W .T M.T .100 .TW 100 M . O W M O W C .CO .TW WW .100Y. .TW WW .100Y.C M.TW M 00Y O 1 W M . O W .C O W W WW W 00Y Y.CFEATURES WW .100Y.C M.TW 1 0 T QUICK START M.T . . 0 O 1 W M . O W C . W Y COAD8231 WSet TW 1. These jumper settings ensure WW 00Y.Two WW .100Y.C M.TW the jumpers in.Table 100 as shown M . .TWcircuits O 1 W M . O W .C a gain O and op amp W In-amp theW part is enabled of 1. W .TW W 00Y and inM WW .100Y.C M.TW 1 WW .100Y.CDifferential T . . O output W O W OM W Table 0Y.CJumper WW1. Quick TW W 0Start Y.Cto switch WW .100Y.C M.TW jumpers 1 WW .100Easy T M.Settings . . O W M O W Function O supply lines W Decoupled W WW .100Y.C M.TSetting WW .100Y.C M.TW WW .100Y.C M.TW High SDN O W O W .C W W .CO .TW TW 00Y WW .100Y.C M.TW A2 W 1 WW .1GENERAL M.Low . 00Y O W M DESCRIPTION O W C O W Low WW .100Y. .TW 0Yit..CZ1 is M Y.C WW .10on .TW A1 WW The M .TW 00AD8231-EVALZ has two AD8231s mounted the O 1 W A0 Low M . W O W W .CO .TW Wconfigured .Cthe WW .100Y.C Low Wof the board.W left .side It is to allow 0Y Yon CS 0 0 WW AD8231 T M.T 1 0 M . O 1 W M . O W C O and op amp separately. W access of the.C in-amp is the AD8231 .C WW .100Y. .TW W WasWaZ2 00Youtput M.TW 0Y side ofM WW on the M .Tboard. 1 0right . the It is set up differential O 1 W . O W Connect the ground GND supply to .C and connect O W lead0to0Y W .TW aa25VVsource W Y.C WW .100Y.C M.TW+VS. ConnectWa 1 V source 1 0 WWconfiguration. T M . . 0 to –INA, and connect to O 1 W OM and the supplies are WW W. outputs, .CO .TW Y.atCOUTA..TW Wrouted C . 0 Y W W Inputs, references, to test +INA. 3.5 V should now appear W 0 0 Y W 0 W .T .10 W.1 Y.COM W .10easy OM Wselect OM SDN, CS, and the gain W Wfor C points connectivity. pins . W C W . The output equation for the1AD8231 with a .gain Y W W 0 W .T W(A0 to A2) M T of 1 is . 00 .TW These jumpers 10both 0are0Yrouted toM M . O 1 jumpers. control W . O W C V − V + V = V . As shipped, the evaluation +INA −INA REF OUT . O W board C WW pin.1driven WW When .Tsupply Whigh position,WitsWcorresponding 00Y to halfM 0Y.C M.has Y TW AD8231s. a .jumper is in the 0 0 W T . the in-amp reference the voltage. 1 0 . O W M the jumper is in the W Wposition,Y.CO .C OWhen W W.1 toYVS. W pin isW connected low Y C W . 0 W T Therefore, the output voltage is 2 V – 1 V + 2.5 V = 3.5 V. . W W W M .10 M.T .100 O W it is connected .10to0ground.OM.T O W C . W W .C DUAL W W Y.C The top.Tand WW .1for .TWSUPPLIESW W.100Y OM.TW 00Y 00layers. M TheW PCB has four bottom layers are used 1 M . O W C W WGND Y.labeled VS.Tand Wplanes. 00Y.C The supplies W on the AD8231-EVALZ .COlayers.are WW .100are W Y W T routing, and the two internal power and ground . 0 WW T M 1 0 M . O 1 W M . because most applications are single supply. However, dual W W W Y.C WW 00Y.CO .TW .CO .T 0 Wwith T . W BOARD 0 Y W 1 0 supplies can also be used this evaluation board, as WW .1EVALUATION M long as . 1 0 M . O W M O W C O W W W Y. 6 V. .TSimply WW .100Y.Cthe difference .TWbetween theWtwo supplies 10is0 less than WW .100Y.C M.TW M . M O W O connect the negative supply toW the GND terminal. W C For example, O W C 0Y.voltage W V to GND. .TW 0Any WW .100Y.connect .TVWto +VS and −2.5 1 WW .100Y.C M.TW M +2.5 . connected M O W O W C . O W C also appears Y to.GND GND2, and WW .TW WW .100Y .TW at the GND1, 100GND3 terminals; WW .100Y.C M.TW M . M O W O W therefore, take care when connecting equipment. O W Y.C WWexternal .TW WW .100Y.C M.TW 100 WW .100Y.C M.TW M . O W O THE OP AMPW W CONFIGURING .C O W W .TW 00Y WW .100Y.C M.TW 1 WW .100Y.C M.TW M . O By default, the op amp in Z1 is configured as a unity-gain buffer W O W C O W W .C Y. amp .TW W pin. A W WW .driving resistor divider .Treference 100at the opO 00Y the in-amp WW .100Y.C M.TW M . 1 M W Ovoltage at midsupply. When W input sets .Camp for .TW O W W C . the using this op Y W C W . 0 Y W W W Y W .T W M .10 REF pin .100applications, M.T .100 other theW in-amp OM remove R8 and drive W W .CO .TW O W C . Y W C W . 0 Y W W W 0 0 Y W T . with a0different source. W M .1 .T 00 W.1 Y.COM VS W WW 00Y.CO .TW W.1 Y.COM W W W W W .T W Figure.11.00 .100 W.1 Y.COM W M.T OM R7 W O W W C . W C W OP_OUT .T W 10kΩ 00 0Y R10 W TW WW .100Y. 0Ω M. .10OP_IN W.1 Y.COM M.T O W O W W C . W REF .100 R13 WW .100Y .TW WW .100Y.C M.TW M.T 0Ω R8 M O W O W C . O 0Ω W WW .100Y .T WW .100Y.C M RC11 .TW R12 WW .100Y.C M.TW OM 10kΩ W O W C . O 0Ω W W C . Y W WW .100Y TW WW .100Y.C M.TW .100 M.Op OM W O W Figure.2. Default Amp Configuration C . O W W C Y W C W . 0 Y W W 0 W WW .100Y M.T .100 W.1 M.T Rev. 0 O W O W W C . W W .C purposes. Y W Evaluation boards are only intended for device evaluation Yproduction W WW and.1not .TorW 00for M.T .100 Evaluation boards are supplied “as is” and without warranties of any kind, express, implied, M O W O W C statutory including, but not limited to, any implied warranty of merchantability or fitness for a WW .100Y. .TW 0Yany.Cpatents orMother WW particular purpose. No license is granted by implication or otherwise under .TW 0 M 1 . O W intellectual property by application or use of evaluation boards.W Information furnishedO by Analog Y.C by Analog.TW WW .100Y.C Devices is believed to be accurate and reliable. However, 0assumed WnoWresponsibility 0isparties 1 M Devices for its use, nor for any infringements of patents or other rights of.third that may result W O Technology U.S.A. from its use. Analog Devices reserves the right to change devices at any time WWor specifications W One Y.C WWWay, P.O. Box 9106, Norwood, MA 02062-9106, W T www.analog.com Tel: 781.329.4700 . 00respective without notice. Trademarks and registered trademarks are the property of.1 their owners. OM Fax: 781.461.3113 ©2008 Analog Devices, Inc. All rights reserved. Evaluation boards are not authorized to be used in life support devicesW or systems. WW .100Y.C M.TW O W WW .100Y.C 07016-002 07016-001 Zero Drift, Digitally Programmable Instrumentation Amplifier Evaluation Board AD8231-EVALZ 13 8 14 7 15 07016-005 07016-003 07016-004 OP_NEG OP_OUT DIFF_REF 5 6 16 13 8 14 7 15 6 OP_IN 5 16 O W Y.C 0 0 1 M.T . O W C . W WW .100Y M.T O W WW .100Y.C M.TW .TW M AD8231-EVALZ WW 00Y.CO .TW .CO .TW Y W 0 0 M .1 W.1 Y.COM W WW 00Y.CO .TW W VS W W .T 00 W.1 Y.COM W W.1 Y.COM W W W W W M.T .100 .TW 100 CSOM.T . O W M C1 + W C .CO .10µF WW .100Y. .TW WW .100Y.C M.TW TW M 00Y O 1 W M . O W O W WW .100Y.C M.TW W Y.C WW A1 .1A000Y.C M.TW 0 T . 0 1 M . W WW 00Y.CO .TW .CO .TW A2W Y W WW 00Y.CO .TW SDN 0 W 0 M .1 W.1 Y.COM W WW 00Y.CO .TW W.1 Y.COM W W W W W .T 00 W W.1 Y.COM W M.T .100 VS OM W.1 Y.CVS O W W W C W . W .T W1 12 1 100 0 12 W T . 0 WW .100Y T M . . 1 M . O W M C2 C7 W .CO WW 00Y W .COC3 LOGIC 0Y.C M.TW 11 C6 WW 2 .10LOGIC 0.1µF 0.1µF SPARE SPARE W Y W T . 11 2 0 WW –INA T . M –DIFFI R3 .1 O W M .10 R1 C4 O W C . O W W C8 W W 0Y Y.C W 3 .10IN-AMP .TW 0Ω SPARE WW +INA.1000ΩY.CSPAREM.T3 W IN-AMP W M.T 10 10010 OUTA M . O W +DIFFI +DIFFO O W C . W W R2 Y.C C C9 C5O W . R4 Y R5 W W 0 Y W T W . W 0 0 W T SPARE SPARE 0Ω0 0Ω . 10kΩ 1 0 W T M . . 0 M .19 4 WW 00Y.CO .TW R6 W.1 Y.COM4 W .CO .TW WW 00YREF W W W OP OP 0 W .1 R8 OM 9 10kΩ –DIFFO W.1 AMP M.TAD8231 AMP .10 OM W C . O W W C . AD8231 Y W C 0Ω0Y W .TW W .TW 100 0 WW .100Y. M . .TW 1 M . O W M O W WW 00Y.CO .TW WW .100Y.C M.TW WW .100Y.C M.TW RC11 10kΩ C10W 1 M . SPARE W O WW 00Y.CO .TW W .CO .TW W C . Y W W R13 W 0 R7 Y W C12 W R12 .T 0Ω 10 00 10kΩ W.1 Y.COM W SPARE W. OM 0Ω W W.1 Y.CVSOM C . W W Y W W W .T W T0ΩW R9 M.T .100 .R10 100 00 M . O 1 W M . SPARE O W C . O W W WW .100Y WW .100Y.C M.TW WW .100Y.C M.TW M.T O W O W O W WW .100Y.C M.TW WW .100Y.C M.TW WW .100Y.C M.TW O WW 00Y.CO .TW W .CO WW C W . Y W W Figure 3. AD8231-EVALZ Schematic W 0 Y W T . W M .1 00 M .10 M.T .CO Ohave WWfor filtering. W.1 Ypads COop ampTW Additional 0603 component beenW placed and routed can also be configured Figure .5Tshows W Y WtoW 00Y.The C . 0 W W 0 W . a Sallen-Key filter. W.1 W M M O how to make allow several otherW types Figure 4 showsW.1 M.T .10of0 op ampOconfigurations. O W WW C12 .100Y.C M.TW Wamp in 0either WnoninvertingW 0Y.C M.TW Y.C how to put the an inverting or gain 0 0 Wop T . 1 . OMconfiguration, drive theWW WW 00Y.CO .TW W.1a noninverting .CO .TW configuration. ToW make C . Y W W 0 Y W 0 W T 00 W.1 Y.COM W OP_IN pin with the incoming and the. OP_NEG pin with a OP_IN W.1 Y.COM OM W W.1 signal W C R10 R13 W . W W 00 .T RC11 bias voltage. ForW an inverting1configuration, drive the OP_NEGW pin M.T .1OP_OUT .TW 100 00Y M . O W M . O W C . O W W theYOP_IN Y with the incoming signal .C pin .with W .TW WW .100Y.C M.TW 100 WW and TWa bias voltage. M . R12 00 O 1 W M . O W O W OP_IN WW .100Y.C M.TW WW .100Y.C M.TW R9 WW .100Y.C M OP_OUT .TW O W O W W Y.C WW 00Y.CO .TW OP_NEG WW C . 0 W W 0 Y W W M.T .1 .T 1 00 M . O 1 W M . R12 O W C O Figure 5. Sallen-Key FilterW W Y. W .TW WW .100Y.C M.TW 100 WR9W .100Y.C M.TW M . O W O W WW .100Y.C M.TW WW 00Y.CO .TW 0Y.C WWORDERING TW OP_NEG . 0 GUIDE W 1 M . O W O W OM W.1 Configuration Figure 4. Inverting orW Noninverting Model W Description Y.C WW .100Y.C M.TW W 0 Y.C WW T . 0 0 W T . 1 0 O 1 W OM W. AD8231-EVALZ Evaluation Board OM W.1 WW .100Y.C M.TW WW .100Y.C M.TW WW .100Y.C M.TW Z = RoHS Part. O WW 00Y.CO .TW W .CO .TW WWCompliant C . Y W W W 0 Y W 0 W .T 00 W.1 Y.COM W.1 Y.COM W W W.1 Y.COM W W W W ESD W CAUTION .T W M.T .100 .T 100 00 M . O 1 W M . O W C . O W WW .100Y .T WW .100Y.C M.TW WW .100Y.C M.TW OM W O W C . O W W C . Y W W WW .100Y WW .100Y.C M.TW .100 M.T OM W O W C . O W W C . Y W C W . 0 Y W W 0 W WW .100Y M.T .100 W.1 M.T O W O W W C . W W Y W W WW .100Y.C M.TW M.T .100 O W O W C WW .100Y. .TW WW .100Y.C M.TW M O ©2008 Analog Devices, Inc. All rights reserved. Trademarks and W W .CO .TW registered trademarks are the property of their respective WW .100Y.C WW owners. 00Y EB07016-0-11/08(0) 1 M . W O W WW WW .100Y.C M.TW Rev. O 0 | Page 2 of 2 W WW .100Y.C M.TW O W WW .100Y.C 1