Precision Operational Amplifier NJM79 FEATURES Precision V IO =6µV max. V IO =µv max. (Ta=-ºC to +8ºC) Low Offset Drift ΔV IO /ΔT=.9µV/ºC max. (Ta=- to +8ºC) Specified for ±V and ±V operation CMR db min. Low Noise V NI =8nVrms typ. at f= to Hz en=8nv/ Hz typ. at f=hz Open Loop Gain Av=dB min. Guaranteed Temperature Ta=-ºC to +8ºC Unity Gain Stable Operating Voltage Vopr=±V to ±8V Unity Gain Frequency f T =.MHz typ. Supply Current Icc=mA max. Package SOP8 JEDEC mil PACKAGE OUTLINE NJM79E ( SOP8 ) GENERAL DESCRIPTION The NJM79 is a high performance operational amplifier features very low offset voltage and drift. Features are low offset voltage and drift, hi common mode rejection, low noise and open loop gain. DC characteristics are % tested and specified from to 8ºC. The NJM79 is suitable for high gain circuit amplified small signal and sets required stable behavior over a wide temperature range. APPRICATION Thermocouple sensor Bridge Amplifier Current Sensor Instrumentation Amplifier Reference Voltage Circuit PIN CONFIGURATION PACKAGE DESCRIPTION.±. (Top View) 8 BALANCE 8 BALANCE INPUT +INPUT 7 6 V + OUTPUT.9±. 6.±. V NC.7.7MAX SOP8 MEET JEDEC MS--AA - -
NJM79 ABSOLUTE MAXIMUM RATING (Ta=ºC Unless Otherwise Specified) PARAMETER SYMBOL RATING UNIT Supply Voltage V + /V - ± V Common Mode Input Voltage (Note) V ICM ± V Differential Input Voltage V ID ± V Power Dissipation (Note ) P D 6 mw Operating Temperature Topr - to +8 ºC Storage Temperature Tstg - to + ºC (Note) For supply voltage less than ±V, the maximum input voltage is equal to the supply voltage. (Note) Mounted on the EIA/JEDEC standard board (76...6mm, two layer, FR-). RECOMMENDED OPERATING VOLTAGE PARAMETER SYMBOL TEST CONDITION MIN. TYP. MAX. UNIT Supply Voltage V + /V - ± - ±8 V ELECTRONIC CHARACTERISTICS DC CHARACTERISTICS Input Characteristics ( Ta=+ºC, V ICM =V unless otherwise specified) PARAMETER SYMBOL TEST CONDITION MIN. TYP. MAX. UNIT Input Offset Voltage V IO - 6 µv V IO Ta=- to +8ºC - µv Input Offset Voltage Drift ΔVio/T Ta=- +ºC / Ta=+ºC +8ºC -..9 µv/ºc Common Mode Input Voltage Range V ICM ± ± - V V ICM Ta=- to +8ºC ± ±. - V Common Mode Rejection Ratio CMR V CM =V -V / V CM =V +V - db CMR Ta=- to +8ºC, V CM =V -V / V CM =V +V - db Supply Voltage Rejection Ratio SVR to ±8V - db SVR Ta=- to +8ºC, to ±8V - db Input Bias Current I B -...8 na I B Ta=- to +8ºC -..7 6 na Input Bias Current Drift ΔI B /T Ta=- +8ºC - 8 6 pa/ºc Input Offset Current I IO -..8 na I IO Ta=- to +8ºC -.. na Input Offset Current Drift ΔI IO /T Ta=- +8ºC -. 7 pa/ºc Differential Input Impedance R ID Theoretical value by design. - 9 - MΩ Common-Mode Input Impedance R IC Theoretical value by design. - 8 - GΩ Input Offset Voltage Trim Viotri Rp=kΩ - ± - mv Voltage Gain Av R L =kω, Vo= -V V / V +V / -V +V - db Av Ta=- to +8ºC, R L =kω, Vo= -V V / V +V / -V +V 6 6 - db - -
NJM79 DC CHARACTERISTICS PARAMETER SYMBOL TEST CONDITION MIN. TYP. MAX. UNIT Output Characteristics Maximum Output Voltage V OM R L =kω ±. ±. - V V OM Ta=- to +8ºC, R L =kω ±. ±. - V V OM R L =kω ±. ±. - V V OM Ta=- to +8ºC, R L =kω ±. ±. - V V OM R L =kω ±. ±. - V Output Impedance R O Open-Loop - 6 - Ω Supply Characteristics Supply Current I CC A V =+, R L = -.6 ma I CC Ta=- to +8ºC, A V =+, R L = -.7. ma I CC, A V =+, R L = -.8.7 ma Power Dissipation P D A V =+, R L = - 6 mw P D, A V =+, R L = -.. mw AC CHARACTERISTICS PARAMETER SYMBOL TEST CONDITION MIN. TYP. MAX. UNIT Frequency Characteristics Unity Gain Frequency f T A V =+, R L =kω, CL=pF -. - MHz Slew Rate +SR RISE, A V =+, V IN =Vpp, R L =kω, C L =pf.. - V/µs -SR FALL, A V =+, V IN =Vpp, R L =kω, C L =pf.. - V/µs Noise Characteristics Equivalent Input Noise Voltage V NI fo=hz to Hz - 8 - nvrms Equivalent Input Noise Current I NI fo=hz to Hz - - parms - -
NJM79 ELECTRONIC CHARACTERISTICS Input Characteristics ( Ta=+ºC, V ICM =V unless otherwise specified) PARAMETER SYMBOL TEST CONDITION MIN. TYP. MAX. UNIT Input Offset Voltage V IO - 7 µv V IO Ta=- to +8ºC - µv Common Mode Input Voltage Range V ICM ± ±.9 - V V ICM Ta=- to +8ºC ± ±. - V Common Mode Rejection Ratio CMR V CM =V -V / V CM =V +V - db CMR Ta=- to +8ºC, V CM =V -V / V CM =V +V - db Input Bias Current I B -..7 na I B Ta=- to +8ºC -. 6 na Input Offset Current I IO -..8 na Voltage Gain Output Characteristics I IO Ta=- to +8ºC -.. na Av Av Open-Loop, R L =kω, Vo= -V V / V +V / -V +V - db Ta=- to +8ºC, Open-Loop, R L =kω, Vo= -V V / V +V / -V +V - db Maximum Output Voltage V OM R L =kω ±. ±. - V Supply Characteristics V OM Ta=- to +8ºC, R L =kω ±. ±. - V V OM R L =kω ±. ±. - V V OM Ta=- to +8ºC, R L =kω ±. ±. - V Supply Current I CC A V =+, R L = -.8. ma I CC Ta=- to +8ºC, A V =+, R L = -.9. ma - -
NJM79 EXPLANATION OF MEASUREMENT CONDITION PARAMETER Explanation Input Offset Voltage Drift Input Offset Voltage Drift = ΔV IO / Δt Δt : Amount of Temperature change. ΔV IO : Amount of Input Offset Voltage. Common Mode Input Voltage range A range of input voltage at which the operational amplifier can function. Common Mode Rejection Ratio CMR = log ( ΔV IN / ΔV IO ) ΔV IN : Amount of Input Voltage. ΔV IO : Amount of Input Offset Voltage. Supply Voltage Rejection Ratio SVR = log ( ΔV S / ΔV IO ) ΔV S : Amount of supply Voltage. ΔV IO : Amount of Input Offset Voltage. Common Mode Input Impedance R INCM = ΔV IN / ΔI B ΔV IN : Amount of Input Voltage. ΔI B : Amount of Input bias current. Voltage Gain AV = log ( ΔV IN / ΔV O ) ΔV O : Amount of output Voltage. ΔV IN : Amount of Input Voltage. - -
NJM79 Input Offset Voltage Distribution Input Offset Voltage Distribution,Ta=,Ta= Number Of Amplifiers Number Of Amplifiers -7-6----- 6 7 Input Offset Voltage [μv] -7-6----- 6 7 Input Offset Voltage [μv] Input Offset Voltage Drift Distribution Input Offset Voltage Drift Distribution,Ta=- to,ta= to 8 Number Of Amplifiers Number Of Amplifiers - -.8 -.6 -. -....6.8 Input Offset Voltage Drift [μv/ ] - -.8 -.6 -. -....6.8 Input Offset Voltage Drift [μv/ ] Input Offset Voltage Drift Distribution Input Offset Volotage Drift Distribution,Ta=- to,ta= to 8 Number Of Amplifiers Number Of Amplifiers - -.8 -.6 -. -....6.8 Input Offset Voltage Drift [μv/ ] - -.8 -.6 -. -....6.8 Input Offset Voltage Drift [μv/ ] - 6 -
NJM79 Input Offset Voltage [μv] 8 6 - - -6-8 - Input Offset Voltage vs. Temperature, V CM =V - - 7 Ambient Temperature [ºC] Input Offset Voltage [μv] 8 6 - - -6-8 - Input Offset Voltage vs. Temperature, V CM =V - - 7 Ambient Temperature [ºC] Input Offset Voltage vs. Temperature VCM=V Input Offset Voltage vs. Temperature VCM=V Input Offset Voltage [μv] - Sample (±V) Sample (±V) Sample (±V) Sample (±V) Sample (±V) Sample (±V) Input Offset Voltge [μv] - - - - 7 - - - 7 Input Offset Voltage vs. Supply Voltage VCM=V Input Bias Curent vs. Supply Voltage VCM=V Input Offset Voltge [μv] Sample Sample Sample Input Bias Current [na] Sample Sample Sample - 8 6 Supply Voltage [±V] - 8 6 Supply Voltage [±V] - 7 -
NJM79 8 Variation in Input Offset Voltage vs. Common Mode Input Voltage 6 Input Offset Voltage vs. Common Mode Input Voltage Ta= Variation in Input Offset Voltage [µv] 6 - - -6-8 - - - Common Mode Input Voltage [V] Input Offset Voltage [μv] - Sample (±V) Sample (±V) Sample (±V) Sample (±V) Sample (±V) Sample (±V) - - - - Common Mode Input Voltage [V] Input Offset Voltage vs. Common Mode Input Voltage Ta= 6 Input Offset Voltage vs. Common Mode Input Voltage (Temperature) 6 Input Offset Voltage [μv] - V+/V-=±V V+/V-=±V V+/V-=±V V+/V-=±8V Input offset Voltage [μv] - Ta= Ta=- - - - - - Common Mode Input Voltage [V] - - - - Common Mode Input Voltage [V] Input Offset Voltage vs. Supply Voltage (Temperature) Vcm=V Warm Up Input Offset Voltage Drift, Gv=dB, Ta= Input offset Voltage [μv] Ta=- Ta= Input Offset Voltage Change [μv] 8 6 Supply Voltage [±V] - Time From Power Supply Turn On [sec] - 8 -
NJM79 Input Offset Voltage vs. Output Voltage Input Offset Voltage vs. Trim Resistance -., Gv=dB, R L=kΩ, Ta=, Gv=6dB, Ta= - Input Offset Voltage [uv] -. - -. - -. Input Offset Voltage [mv] - - -6 - -6. - - - Output Voltage [V] - Trim resistance Rp [kω].8 Equivalent Input Noise Voltage, BP=~Hz.8 Equivalent Input Noise Voltage, BP=~Hz Equivalent Input Noise Voltagte [μv].6.. -. -. -.6 Equivalent Input Noise Voltage [μv].6.. -. -. -.6 -.8 6 8 Time [sec] -.8 6 8 Time [sec] 6 Equivalent Input Noise Voltage Rf=kΩ, Rs=Ω, Rg=Ω, Ta= Equivalent Input Noise Voltage [nv/ Hz] 8 6-9 -
NJM79 Input Bias Current vs. Temperature VCM=V Input Bias Current vs. Temperature VCM=V Input Bias Current [na] 8 6 Sample (±V) Sample (±V) Sample (±V) Sample (±V) Sample (±V) Sample (±V) Input Bias Current [na] 8 6 - - 7 - - 7 Input Bias Current vs. Common Mode Input Voltage (Temperature) Input Bias Current vs. Common Mode Input Voltage Ta=. Ta=-. Input Bias Current [na].. Ta= Input Bias Current [na].. -. -. - - - - Common Mode Input Voltage [V] - - - - - Common Mode Input Voltage [V] Input Offset Current vs. Temperature VCM=V 6 Input Offset Current vs. Temperature VCM=V Input Offset Current [na] Sample (±V) Sample (±V) Sample (±V) Sample (±V) Sample (±V) Sample (±V) Input Offset Current [na] - - 7 - - - 7 - -
NJM79 Input Offset Current vs. Common Mode Input Voltage (Temperature). Input Offset Current vs. Common Mode Input Voltage Ta=. Input Offset Current [na]. -. - Ta=- Ta= Input Offset Current [na]. -. - -. -. - - - - Common Mode Input Voltage [V] - - - - - Common Mode Input Voltage [V] Common Mode Rejection Ratio vs. Temperature VICM=V - +V to V + -V Common Mode Rejection Ratio vs. Frequency, Gv=8dB, Ta= Common Mode Rejection Ratio [db] Common Mode Rejection Ratio [db] 8 6 - - 7 Supply Voltage Rejection Ratio vs. Frequency V + /V - =±. to ±.V, Gv=8dB, Ta= Supply Voltage Rejection Ratio vs. Temperature to ±V Supply Voltage Rejection Ratio [db] 8 6 +SVR -SVR Supply Voltage Rejection Ratio [db] - - 7 Temperature [ ] - -
NJM79 Voltage Gain vs. Temperature RL=kΩ 6 Voltage Gain vs. Supply Voltage (Temperature) RL=kΩ Voltage Gain [db] Voltage Gain [db] Ta=- Ta= - - 7 8 6 Supply Voltage [±V] Maximum Output Voltage vs. Load Resistance (Temperature) Maximum Output Voltage vs. Load Resistance Ta= Maximum output Voltage [V] - - Ta=- Ta= Ta= Ta=- Maximum Output Voltage [V] - - - - Load Resistance [Ω] - Load Resistance [Ω] Output Voltage vs. Output Current Maximum output Voltage vs. Temperature RL=kΩ Output Current [V] - - +VOM Ta=- +VOM Ta= +VOM -VOM Ta=- -VOM Ta= -VOM Maximum output Voltage [V] - - - - Output Current [ma] - - - 7 Ambient Temperature [Ω] - -
NJM79 THD+N vs. Output Voltage THD+N vs. Frequency, Gv=dB, R F=kΩ, Rs=kΩ, Ta=, Gv=dB, R F=kΩ, Rs=kΩ, Vout=mVrms, Ta= f=khz.8 THD+N [%].. f=khz THD+N [%].6.. f=hz f=hz... Output Voltage [Vrms]. 6 db Gain/Phase vs. Frequency Gv=dB, R F=kΩ, Rs=Ω, 8 RT=Ω, Ta= 8 db Gain/Phase vs. Frequency (Temperature), Gv=dB, R F=kΩ, Rs=Ω, RT=Ω 8 8 Voltage Gain [db] 6 Gain Phase 6-6 - - - -8 6 7 Phase [deg] Voltage Gain [db] 6 Ta=- Gain Ta= 6 Phase -6 - Ta=- Ta= - - -8 6 7 Phase [deg] Voltage Gain [db] db Gain/Phase vs. Frequency (Load Capacitance), Gv=dB, R F=kΩ, Rs=Ω, RT=Ω, Ta= 8 8 6 Gain Phase CL=.μF CL=.μF CL=.7μF CL=.μF CL=F -6 CL=.μF - CL=.μF CL=.7μF - CL=.μF CL=F - -8 6 7 6 Phase [deg] Voltage Gain [db] db Gain/Phase vs. Frequency (Temperature), Gv=dB, R F=kΩ, Rs=Ω, R T=Ω 8 8 6 gain Phase Ta=- Ta= -6 - Ta=- Ta= - - -8 6 7 6 Phase [deg] - -
NJM79 V.F. Peak Gv=dB, R T=Ω, CL=.μF, Ta= V.F.Peak (Temperature), Gv=dB, R T=Ω, CL=.μF Voltage Gain [db] Voltage Gain [db] Ta=- Ta= - - - 6-6 V.F.Peak (Load Capacitance) Voltage Gain [db], Gv=dB, R T=Ω, Ta= CL=.μF CL=.μF CL=.7μF CL=.μF CL=F - - 6.6 Pulse Response (Temperature), RL=kΩ, CL=pF.8..6 Input Pulse Response (Temperature), R L=kΩ, CL=pF.8... Output [V].8. Input Ta= -. -.8 -. Input [V] Output [V].8. Output Ta=- Ta= -. -.8 -. Input [V] -. Output Ta=- -.6 -. -.6 -.8 - - - 6 Time [μs] -.8 - - - 6 Time [μs] - -
NJM79.6 Pulse Response (Temperature), RL=kΩ, CL=pF.8..6 Input Pulse Response (Temperature), RL=kΩ, CL=pF.8... Output [V].8. Input Ta= -. -.8 -. Input [V] Output [V].8. Output Ta=- Ta= -. -.8 -. Input [V] -. Output Ta=- -.6 -. -.6 -.8 - - - 6 Time [μs] -.8 - - - 6 Time [μs].6 Pulse Response (Supply Voltage, Load Capacitance) RL=kΩ, Ta=.8..6 Input Pulse Response (Supply Voltage, Load Capacitance) RL=kΩ, Ta=.8... Output [V].8 Input CL=pF -.. -.8 CL=pF -. CL=pF -. Output -.6 CL=pF -.8 - - Time [μs] Input [V] Output [V].8. Output CL=pF CL=pF -. -.8 -. CL=pF -. -.6 CL=pF -.8 - - Time [μs] Input [V] Pulse Response (Load Capacitance) Pulse Response (Load Capacitance) Output [V].6..8. Input Output, R L=kΩ, Ta= CL=.μF CL=.7μF CL=.μF CL=.μF.8. -. -.8 -. Input [V] Output [V].6..8. Input Output, R L=kΩ, Ta= CL=.μF CL=.μF CL=.7μF.8. -. -.8 -. Input [V] -. -.6 -. CL=.μF -.6 -.8 - - - 6 Time [μs] -.8 - - - 6 Time [μs] - -
NJM79 Slew Rate vs. Temperature RL=kΩ Unity Gain Frequency vs. Temperature Gv=dB, R F=kΩ, Rs=Ω, R T=Ω Slew Rate [V/μs].8.6.. FALL RISE FALL RISE - - 7 Unity Gain Frequency [MHz].. - - 7 Temperature [ ] Supply Current vs. Supply Voltage (Temperature) RL=.. Supply Current vs. Temperature RL= Ta= Supply Current [ma].6..8 Ta=- Supply Current [ma].6..8.. 8 6 Supply Voltage [±V] - - 7-6 -
NJM79 Application Information Power Supply Bypassing The NJM79 is a high precision operational amplifier featuring low offset voltage, high voltage gain, high CMR, high SVR and so on. To maximize such a high performance with stable operation, the NJM79 should be operated by clean and low impedance supply voltage. So, the bypass capacitor should be connected to the NJM79 s both power supply terminals (V+ and V-) as shown in Fig.. The bypass capacitors should be placed as close as possible to IC package V+ + 7 NJM79 6 V- Fig. Power Supply Bypassing Circuit Thermoelectric Effect The NJM79 is a high precision operational amplifier featuring low offset voltage and low offset voltage thermal drift. To achieve such a high performance, take care about thermoelectric effect possibly occurs on each input terminal of the NJM79. Generally, if there are thermal mismatches at the junction of different types of metals, the thermoelectric voltage (Seebeck effect) occurs at the junction. The thermoelectric voltages possibly occur at the junction of PCB metal patterns and NJM79 s each input terminal metal. If there is thermal mismatch in-between NJM79 s each input terminal metal, the thermoelectric voltages generated on each input terminal possibly have different voltage each. This voltage difference causes offset voltage and offset voltage thermal drift of the NJM79. To minimize this voltage difference, the thermal mismatch in-between NJM79 s each input terminal and PCB metal should be minimized. Offset Voltage Adjustment The NJM79 has offset voltage trim terminals (pin and pin8) as shown in below Fig.. By connecting external potentiometer in the range of Kohm, the offset voltage trim range is ±mv. This offset voltage trim is effective only for offset voltage at room temperature, not for offset voltage thermal drift. If offset voltage adjustment is not in use, leave pin and pin8 open (un-connected). Rp=kΩ V+ + 8 7 NJM79 6 V- Fig. Offset Voltage Trim Circuit - 7 -
NJM79 Differential Amplifier Differential amplifier (see below Fig.) is used in high accuracy circuit to improve common mode rejection ratio (CMR). A matching between the ratio R/R = R/R and R=R makes the high CMR. For example, acceptable error range to obtain CMR of db or more is about.ppm. R V+ R 7 R NJM79 + 6 R V- Fig. Differential Amplifier [CAUTION] The specifications on this data book are only given for information, without any guarantee as regards either mistakes or omissions. The application circuits in this data book are described only to show representative usages of the product and not intended for the guarantee or permission of any right including the industrial rights. - 8 -