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OPA1642

JFET-Input Audio Operational Amplifier

The OPA1642 is a jfet-input audio operational amplifier from Texas Instruments. View the full OPA1642 datasheet below including electrical characteristics, absolute maximum ratings.

Manufacturer

Texas Instruments

Category

JFET-Input Audio Operational Amplifier

Overview

Part: OPA1641, OPA1642, OPA1644 — Texas Instruments

Type: JFET-Input Audio Operational Amplifiers

Description: The OPA164x series are JFET-input, ultralow distortion, low-noise operational amplifiers with rail-to-rail output, operating from ±2.25 V to ±18 V supplies, featuring 5.1 nV/√Hz noise, 0.00005% THD+N, and 1.8 mA quiescent current per channel.

Operating Conditions:

  • Supply voltage: ±2.25 V to ±18 V (dual supply) or 4.5 V to 36 V (single supply)
  • Operating temperature: -40 to 85 °C

Absolute Maximum Ratings:

  • Max supply voltage: 40 V
  • Max input current: ±10 mA
  • Max junction temperature: 150 °C

Key Specs:

  • Total harmonic distortion + noise (THD+N): 0.00005% at 1 kHz, V_O = 3 V RMS
  • Input voltage noise density (e_n): 5.1 nV/√Hz at 1 kHz
  • Slew rate (SR): 20 V/μs
  • Gain-bandwidth product (GBW): 11 MHz
  • Input bias current (I_B): ±2 pA (V_CM = 0 V)
  • Quiescent current (I_Q): 1.8 mA per amplifier (I_OUT = 0 A)
  • Open-loop voltage gain (A_OL): 134 dB (V_S = ±18 V)
  • Short-circuit current (I_SC): 36 mA (Source)

Features:

  • True JFET Input Operational Amplifier With Low Input Bias Current
  • Low Noise: 5.1 nV/√Hz at 1 kHz
  • Ultralow Distortion: 0.00005% at 1 kHz
  • High Slew Rate: 20 V/μs
  • Unity Gain Stable
  • Rail-to-rail Output
  • Wide Supply Range: ±2.25 V to ±18 V

Applications:

  • Professional Audio Equipment
  • Analog and Digital Mixing Consoles
  • Broadcast Studio Equipment
  • High-End A/V Receivers
  • High-End Blu-ray™ Players

Package:

  • SOIC (8)
  • VSSOP (8)
  • SOIC (14)
  • TSSOP (14)

Features

  • 1 · Superior Sound Quality
  • True JFET Input Operational Amplifier With Low Input Bias Current
  • Low Noise: 5.1 nV/ √ Hz at 1 kHz
  • Ultralow Distortion: 0.00005% at 1 kHz
  • High Slew Rate: 20 V/ μ s
  • Unity Gain Stable
  • No Phase Reversal
  • Low Quiescent Current: 1.8 mA per Channel
  • Rail-to-rail Output
  • Wide Supply Range: ±2.25 V to ±18 V
  • Single, Dual, and Quad Versions Available

Applications

  • Professional Audio Equipment
  • Analog and Digital Mixing Consoles
  • Broadcast Studio Equipment
  • High-End A/V Receivers
  • High-End Blu-ray™ Players

Electrical Characteristics

at TA = 25°C, VS = 4.5 V to 36 (±2.25 V to ±18 V), RL = 2 k Ω connected to midsupply, and VCM = VOUT = midsupply (unless otherwise noted)

PARAMETERPARAMETERTEST CONDITIONSTYPMAXUNIT
AUDIO PERFORMANCEAUDIO PERFORMANCEAUDIO PERFORMANCEAUDIO PERFORMANCEAUDIO PERFORMANCEAUDIO PERFORMANCE
THD+NTotal harmonic distortion + noiseG = +1, f = 1 kHz, V O = 3 V RMS0.00005% -126dB
IMDIntermodulation distortion DIM 30 15-kHzSMPTE/DIN two-tone, 4:1 (60 Hz and 7 kHz), G = +1, V O = 3 V RMS (3-kHz square wave and sine wave), G = +1,0.00004% -128 0.00008% -122dB dB
FREQUENCY RESPONSEFREQUENCY RESPONSEFREQUENCY RESPONSEFREQUENCY RESPONSEFREQUENCY RESPONSEFREQUENCY RESPONSE
GBWGain-bandwidth productG = 111MHz
SRSlew rate Full-power bandwidth (1)G = 1 V O = 1 V P20 3.2V/ μ s MHz
NOISEInput voltage noise Input voltage noise densityf = 20 Hz to 20 kHz f = 10 Hz f = 100 Hz4.3 8 5.8 5.1μ V PP nV/ √ Hz
e nInput current noise densityf = 1 kHz0.8
I nVOLTAGE Input offset voltagef = 1 kHzfA/ √ Hz mV
OFFSETV = ±18 V
V OS PSRR INPUT BIASV OS vs power supply CURRENTS V S = ±2.25 V to ±18 V1 0.143.5 2μ V/V
I B I OSInput bias current V CM = Input offset current Differential0 V R L = 10 k Ω (V-) + 0.35 V ≤ V O ≤ (V+) - 0.35 R = 2 k Ω±2±20 ±20pA pA
INPUT V CM CMRRV CM = VOLTAGE RANGE Common-mode voltage range Common-mode rejection ratio V CM = V S =0 V (V-) - 0.1 V to (V+) - 3.5 V, ±18 V V CM = (V-) - 0.1 V to (V+) - 3.5 V±2(V+)-3.5V dB Ω \
INPUT IMPEDANCECommon-mode OPEN-LOOP GAIN
Open-loop voltage gain (V-) + 0.2 V		≤ V O ≤ (V+) - 0.2 V,126 10 13 \\8 10 13 <br>pF
A OLL
V,		134 126dB

Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted) (1)

MINMAXUNIT
V SSupply voltage40V
V INInput voltage (2)(V-) - 0.5(V+) + 0.5V
I INInput current (2)±10mA
V IN(DIFF)Differential input voltage±VSV
I OOutput short-circuit (3)ContinuousContinuous
T AOperating temperature-55125°C
T JJunction temperature-65150°C
T stgStorage temperature-65150°C

Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)

MINNOMMAXUNIT
Supply voltage (V+, V-)Single supply4.536V
Supply voltage (V+, V-)Dual supply±2.25±18V
Specified temperature-4085°C

Thermal Information

OPA1641,OPA1642OPA1642OPA1644OPA1644
THERMAL METRIC (1)THERMAL METRIC (1)D (SOIC)DGK (VSSOP)D (SOIC)PW (TSSOP)
8 PINS8 PINS14 PINS14 PINS
R θ JAJunction-to-ambient thermal resistance16018097135
R θ JC(top)Junction-to-case (top) thermal resistance75555645
R θ JBJunction-to-board thermal resistance601305366
ψ JTJunction-to-top characterization parameter9n/a19n/a
ψ JBJunction-to-board characterization parameter501204660
R θ JC(bot)Junction-to-case (bottom) thermal resistancen/an/an/an/a

Typical Application

The OPA1641, OPA1642, and OPA1644 are unity-gain stable, audio operational amplifiers with very low noise, input bias current, and input offset voltage. Applications with noisy or high-impedance power supplies require decoupling capacitors placed close to the device pins. In most cases, 0.1μ F capacitors are adequate. Figure 32 shows a simplified schematic of the OPA1641.

Figure 32. Simplified Internal Schematic

Related Variants

The following components are covered by the same datasheet.

Part NumberManufacturerPackage
OPA1641Texas Instruments—
OPA1642-Q1Texas Instruments—
OPA1642AIDTexas InstrumentsSOIC (8)
OPA1642AIDRTexas Instruments—
OPA1644Texas Instruments—
OPA164XTexas Instruments—
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