FET-Input, Low Power Instrumentation Amplifier datasheet

1 1 INA121 International Airport Industrial Park Mailing Address: PO Box 11400, Tucson, AZ 85734 Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 Tel: (520) 746-1111 Twx: 910-952-1111 Internet: FAXLine: (800) 548-6133 (US/Canada Only) Cable: BBRCORP Telex: 066-6491 FAX: (520) 889-1510 Immediate Product Info: (800) 548-6132 INA121 INA121 INA121 1997 Burr-Brown CorporationPDS-1412 APrinted in May, 1998 FEATURESlLOW BIAS CURRENT: 4pAlLOW QUIESCENT CURRENT: 450 AlLOW INPUT OFFSET VOLTAGE: 200 VlLOW INPUT OFFSET DRIFT: 2 V/ ClLOW INPUT NOISE:20nV/ Hz at f = 1kHz (G =100)lHIGH CMR: 106dBlWIDE SUPPLY RANGE: to 18 VlLOW NONLINEARITY ERROR: maxlINPUT PROTECTION TO 40Vl8-PIN DIP AND SO-8 SURFACE MOUNTFET-Input, Low PowerINSTRUMENTATION AMPLIFIERDESCRIPTIONThe INA121 is a FET-input, low Power instrumenta-tion Amplifier offering excellent accuracy.

2 Its versatilethree-op amp design and very small size make it idealfor a variety of general purpose applications. Low biascurrent ( 4pA) allows use with high can be set from 1V to 10,000V/V with a singleexternal resistor. Internal input protection can with-stand up to 40V without INA121 is laser-trimmed for very low offsetvoltage ( 200 V), low offset drift ( 2 V/ C), andhigh common-mode rejection (106dB at G = 100). Itoperates on Power supplies as low as (+ ),allowing use in battery operated and single 5V sys-tems. Quiescent current is only 450 options include 8-pin plastic DIP and SO-8surface mount. All are specified for the 40 C to+85 C industrial temperature TRANSDUCER AMPLIFIERSB ridge, RTD, ThermocouplelPHYSIOLOGICAL AMPLIFIERSECG, EEG, EMG, RespiratorylHIGH IMPEDANCE TRANSDUCERSlCAPACITIVE SENSORSlMULTI-CHANNEL DATA ACQUISITIONlPORTABLE, BATTERY OPERATED SYSTEMSlGENERAL PURPOSE INSTRUMENTATIONA1A2A3640k 40k 40k 40k 743812 VINVINRGV+V INA121 RefVOG = 1 +50k RG +5 Over-VoltageProtection25k 25k Over-VoltageProtectionSBOS0782 INA121 SPECIFICATIONS: VS = 15 VAt TA = +25 C, VS = 15V, RL = 10k , and IA reference = 0V, unless otherwise noted.

3 [ Specification same as INA121P, : (1) Temperature coefficient of the Internal Resistor in the gain equation. Does not include TCR of gain-setting resistor, , UINA121PA, UAPARAMETERCONDITIONSMINTYPMAXMINTYPMAXU NITSINPUTO ffset Voltage, RTI 200 200/G 500 500/G 300 200/G 1000 1000/G Vvs Temperature 2 2/G 5 20/G[ 15 20/G V/ Cvs Power SupplyVS = to 18V 5 20/G 50 150/G[[ V/VLong-Term Stability [ V/moImpedance, Differential1012 || 1[ || pFCommon-ModeVO = 0V1012 || 12[ || pFInput Voltage RangeSee Text and Typical Curves[Safe Input Voltage 40[VCommon-Mode RejectionVCM = to = 1788672[dBG = 109110085[dBG = 1009610690[dBG = 1000106[dBBIAS CURRENTVCM = 0V 4 50[[pAvs TemperatureSee Typical Curve[Offset Current [pAvs TemperatureSee Typical Curve[NOISE, RTIRS = 0 Voltage Noise: f = 10 HzG = 10030[nV/ Hzf = 100 HzG = 10021[nV/ Hzf = 1kHzG = 10020[nV/ Hzf = to 10 HzG = 1001[ Vp-pCurrent Noise.]]]]]]]]]]]]]]]]]]]]]]

4 F = 1kHz1[fA/ HzGAINGain Equation1 + (50k /RG)[V/VRange of Gain110,000[[V/VGain ErrorVO = 14V to = 1 [ = 10 [ = 100 [ = 1000 [%Gain vs Temperature(1)G = 1 1 10[[ppm/ CG > 1 25 100[[ppm/ CNonlinearityVO = 14V to = 1 [ of FSRG = 10 [ of FSRG = 100 [ of FSRG = 1000 [% of FSROUTPUTV oltage: PositiveRL = 100k (V+) [VNegativeRL = 100k (V )+ [VPositiveRL = 10k (V+) (V+) [[VNegativeRL = 10k (V )+1(V )+ [[VCapacitance Load Drive1000[pFShort-Circuit Current 14[mAFREQUENCY RESPONSEB andwidth, 3dBG = 1600[kHzG = 10300[kHzG = 10050[kHzG = 10005[kHzSlew Rate VO = 10V, G [V/ sSettling Time, = 1 to 1020[ sG = 10035[ sG = 1000260[ sOverload Recovery50% Input Overload5[ sPOWER SUPPLYV oltage Range 15 18[[ [VQuiescent CurrentIO = 0V 450 525[[ ATEMPERATURE RANGES pecification 4085[[ COperating 55125[[ CStorage 55125[[ CThermal Resistance, JA8-Lead DIP100[ C/WSO-8 Surface Mount150[ C/W3 INA121 PIN CONFIGURATIONELECTROSTATICDISCHARGE SENSITIVITYThis integrated circuit can be damaged by ESD.]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]] ]]]]]]]]]]

5 Burr-Brownrecommends that all integrated circuits be handled withappropriate precautions. Failure to observe proper handlingand installation procedures can cause damage can range from subtle performance degradationto complete device failure. Precision integrated circuits maybe more susceptible to damage because very small parametricchanges could cause the device not to meet its Voltage .. 18 VAnalog Input Voltage Range .. 40 VOutput Short-Circuit (to ground) .. ContinuousOperating Temperature .. 55 C to +125 CStorage Temperature .. 55 C to +125 CJunction Temperature .. +150 CLead Temperature (soldering, 10s) .. +300 CNOTE: (1) Stresses above these ratings may cause permanent to absolute maximum conditions for extended periods may degradedevice MAXIMUM RATINGS(1)The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions.

6 BURR-BROWN assumesno responsibility for the use of this information, and all use of such information shall be entirely at the user s own risk. Prices and specifications are subject to changewithout notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrantany BURR-BROWN product for use in life support devices and/or View8-Pin DIP and SO-8 RGV INV+INV RGV+VORef12348765 Top ViewPACKAGESPECIFIEDDRAWINGTEMPERATUREPA CKAGEORDERINGTRANSPORTPRODUCTPACKAGENUMB ER(1)RANGEMARKINGNUMBER(2)MEDIAS ingleINA121P8-Pin DIP006 40 C to +85 CINA121 PINA121 PRailsINA121PA8-Pin DIP006 40 C to +85 CINA121 PAINA121 PARailsINA121 USO-8 Surface-Mount182 40 C to +85 CINA121 UINA121 URails"""""INA121U/2K5 Tape and ReelINA121 UASO-8 Surface-Mount182 40 C to +85 CINA121 UAINA121 UARails"""""INA121UA/2K5 Tape and ReelNOTES: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix C of Burr-Brown IC Data Book.

7 (2) Models with a slash (/) areavailable only in Tape and Reel in the quantities indicated ( , /2K5 indicates 2500 devices per reel). Ordering 2500 pieces of INA121U/2K5 will get a single2500-piece Tape and Reel. For detailed Tape and Reel mechanical information, refer to Appendix B of Burr-Brown IC Data INFORMATION4 INA121 TYPICAL PERFORMANCE CURVESAt TA = +25 C, VS = 15V, unless otherwise Power SUPPLY REJECTIONvs FREQUENCYF requency (Hz) Power Supply Rejection (dB)1010010k100k1M1k120100806040200G = 1000V/VG = 1V/VG = 10V/VG = 100V/VINPUT COMMON-MODE RANGEvs OUTPUT VOLTAGE, VS = 15 VOutput Voltage (V)Common-Mode Voltage (V) 15 100515 5151050 5 10 1510VD/2+ + +VCMVOVD/2 Ref 15V+15VG = 1G 10 POSITIVE Power SUPPLY REJECTIONvs FREQUENCYF requency (Hz) Power Supply Rejection (dB)1010010k100k1M1k120100806040200G = 1000V/VG = 1V/VG = 10V/VG = 100V/VCOMMON-MODE REJECTIONvs FREQUENCYF requency (Hz)Common-Mode Rejection (dB)

8 1010010k100k1M1k120100806040200G = 1000V/VG = 1V/VG = 10V/VG = 100V/VINPUT COMMON-MODE RANGEvs OUTPUT VOLTAGE, VS = 5V, Voltage (V)Common-Mode Voltage (V) 5543210 1 2 3 4 5 4 3 2 1012345VS = 5 VVS = = 1G 10G = 1G 10 GAIN vs FREQUENCYF requency (Hz)Gain (dB)1k10k1M10M100k6050403020100 10 20G = 1000V/VG = 100V/VG = 10V/VG = 1V/V5 INA121 INPUT BIAS CURRENT vs TEMPERATURET emperature ( C)Bias Current (pA) 75 50 250255075100125 IBIOSTYPICAL PERFORMANCE CURVES (CONT)At TA = +25 C, VS = 15V, unless otherwise OVER-VOLTAGE V/I 1 Input Current (mA)Input Voltage (V) 50 40 30 20 1010203040050G = 1V/VG = 1000V/VG = 1V/VFlat region representsnormal linear 15V+15VG = 1000V/VQUIESCENT CURRENT AND SLEW RATEvs TEMPERATURE500475450425400375 75 50 250255075100125 Temperature ( C)Quiescent Current ( A) Rate (V/ s)SRIQSHORT-CIRCUIT CURRENTvs TEMPERATURE 15 14 13 12 11 10 75 50 250255075100125 Temperature ( C)Short-Circuit Current ( A)+ISC ISCSETTLING TIME vs GAIN1000100101101001000 Gain (V/V)Settling Time ( s) BIAS CURRENTvs COMMON-MODE INPUT VOLTAGE1m100 10 10p1p 10 100 1m 20 15 10 505101520 Common-Mode Voltage (V)Input Bias Current (A)6 INA121 TYPICAL PERFORMANCE CURVES (CONT)At TA = +25 C, VS = 15V, unless otherwise VVOLTAGE NOISE TO 10 HzINPUT-REFERRED, G 1001s /divOUTPUT VOLTAGE SWING vs OUTPUT CURRENTV+(V+) (V+) (V+)

9 (V+) (V+) (V ) + (V ) + (V ) + (V ) + (V ) + (V ) 0 2 4 6 8 10 Output Current (mA)Output Voltage Swing (V)+125 C+125 C+85 C+85 C 40 C, 55 C 40 C, 55 C+25 C+25 CINPUT OFFSET VOLTAGE WARM-UP1086420 2 4 6 8 100100200300400500 Time ( s)Offset Voltage Change ( V)INPUT OFFSET VOLTAGE DRIFTPRODUCTION DISTRIBUTIONP ercent of Units (%)Offset Voltage Drift ( V/ C)181614121086420 Typical productiondistribution ofpackaged units. 10 MAXIMUM OUTPUT VOLTAGE vs FREQUENCY3025201510501001k10k100k1 MFrequency (Hz)Peak-to-Peak Output Voltage (Vp-p)G = 1000G = 10 to 100G = 1 INPUT-REFERRED NOISE VOLTAGEvs FREQUENCYF requency (Hz)Voltage Noise (nV/ Hz)1101k10k1001000100101G = 1G = 10G = 1000(BW Limit)G = 1007 INA121 SMALL-SIGNAL STEP RESPONSE(G = 1, 10)TYPICAL PERFORMANCE CURVES (CONT)At TA = +25 C, VS = 15V, unless otherwise STEP RESPONSE(G = 100, 1000)LARGE-SIGNAL STEP RESPONSE(G = 1, 10)LARGE-SIGNAL STEP RESPONSE(G = 100, 1000)10 s/divG = 1050mV/divG = 1100 s/divG = 10050mV/divG = 1000100 s/divG = 105V/divG = 1G = 10005V/divG = 100100 s/div8 INA121 APPLICATION INFORMATIONF igure 1 shows the basic connections required for operationof the INA121.

10 Applications with noisy or high impedancepower supplies may require decoupling capacitors close tothe device pins as output is referred to the output reference (Ref) terminalwhich is normally grounded. This must be a low-impedanceconnection to assure good common-mode rejection. A resis-tance of 8 in series with the Ref pin will cause a typicaldevice to degrade to approximately 80dB CMR (G = 1).SETTING THE GAINGain of the INA121 is set by connecting a single externalresistor, RG, connected between pins 1 and 8:Commonly used gains and resistor values are shown inFigure 1.(1)G=1+50 k RGThe 50k term in Equation 1 comes from the sum of the twointernal feedback resistors of A1 and A2. These on-chipmetal film resistors are laser trimmed to accurate absolutevalues.