OPA632U - 68MHz, 6mA Op Amp Single-Supply SOIC-8 | Texas Instruments
MPN: OPA632U ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.2 | $3.20 |
| 10 | $2.88 | $28.80 |
| 100 | $2.55 | $255.00 |
| 500 | $2.2 | $1,100.00 |
| 1,000 | $1.92 | $1,920.00 |
OPA632U Overview
An operational amplifier (op amp) is a high-gain DC-coupled electronic voltage amplifier with differential inputs and a single-ended output. Within the broader taxonomy, the OPA632 belongs to the voltage-feedback amplifier (VFA) family, which sits under the linear amplifier IC class, which in turn is a sub-category of analog signal-conditioning integrated circuits. The OPA632's distinguishing feature versus general-purpose op amps is its combination of wide bandwidth, high slew rate, and low input voltage noise (6 nV/sqrt(Hz)) in a power-efficient package.
Key features of the OPA632U include 68 MHz unity-gain bandwidth, 100 V/us slew rate, 6 nV/sqrt(Hz) input-referenced voltage noise density, a low 6 mA quiescent current, and an integrated shutdown pin for power saving. The amplifier is unity-gain stable and provides a rail-to-rail output swing that approaches the positive rail and includes ground at the negative input range, easing single-supply signal chain design.
Internally, the OPA632 uses a complementary bipolar architecture with a proprietary input stage that achieves low input bias current while preserving high bandwidth. The architecture delivers low distortion (typically 0.02 percent THD+N at 1 kHz into 600 ohm loads) and excellent DC precision, with a typical input offset voltage of +/-1 mV. The 8-pin SOIC (D) package is pin-compatible with industry-standard single op amp footprints, allowing drop-in replacement in existing designs.
Typical applications of the OPA632U include high-fidelity audio ADC input buffers, active filter blocks, photodiode transimpedance front-ends, professional audio line drivers, and portable instrumentation. In each case, the combination of 68 MHz bandwidth, 6 mA supply current, and shutdown support makes the OPA632 a flexible analog building block for cost-sensitive but performance-critical designs.
When designing with the OPA632U, observe the maximum supply rating of +12 V (or +/-6 V dual) and ensure output loading remains within the datasheet's safe operating area. Decouple the supply pin with a 0.1 uF ceramic capacitor placed within 5 mm of the IC, and use low-ESR bulk capacitance if the supply traces exceed 25 mm. The enable/disable pin should be tied to the positive supply through a 10 kohm resistor if the shutdown feature is not used, to prevent floating-input noise on that pin.
Drop-in alternatives for OPA632U — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with OPA632U (same form factor and footprint) — differing in Package, Slew Rate, Amplifier Type, Operating Temperature Range, RoHS Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
OPA634U
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View Datasheet →LM2904M
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View Datasheet →AD8055ARZ
✅ Drop-In📋 Reference alternative (not in catalog)
MAX4450EUK+T
✅ Drop-In📋 Reference alternative (not in catalog)
OPA632U Maximum Ratings & Electrical Characteristics
| Manufacturer | Texas Instruments (formerly Burr-Brown) |
| Amplifier Type | Voltage Feedback |
| Number of Channels | 1 |
| Slew Rate | 100 V/us |
| Unity-Gain Bandwidth | 68 MHz |
| Supply Current (per channel) | 6 mA |
| Input Voltage Noise Density | 6 nV/sqrt(Hz) |
| Input Offset Voltage (typical) | +/-1 mV |
| Single-Supply Operating Range | +2.5 V to +10 V |
| Dual-Supply Operating Range | +/-2.5 V to +/-5 V |
| Output Swing (5 V supply, 2 kohm load) | 4.8 V |
| Input Common-Mode Range | Includes ground |
| Shutdown Feature | Yes (zero-power disable pin) |
| Operating Temperature Range | -40 C to +85 C |
| Package | 8-SOIC (D) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| MSL Level | 1 (unlimited floor life) |
OPA632U Pin Configuration
| Pin 1 | NC — No connection |
| Pin 2 | IN- — Inverting input |
| Pin 3 | IN+ — Non-inverting input |
| Pin 4 | V- — Negative supply (or ground for single-supply) |
| Pin 5 | SHDN — Shutdown/enable (active low) |
| Pin 6 | V+ — Positive supply |
| Pin 7 | NC — No connection |
| Pin 8 | OUT — Amplifier output |
Typical Applications
OPA632U is suitable for 6 applications: Audio ADC Input Buffer, Active Filter Block, Photodiode Transimpedance Amplifier, Video Line Driver, Portable Instrumentation Front-End, Professional Audio Line Driver.
Audio ADC Input Buffer
The OPA632U is a strong fit for audio ADC input buffers where 6 nV/sqrt(Hz) input noise floor and 68 MHz bandwidth preserve dynamic range above the noise contribution of mid-resolution audio ADCs. Placed between the analog source and the ADC's input network, the part's single-supply 5 V operation eliminates the dual-rail supply cost common in audio paths, and the 4.8 V output swing on a 5 V rail provides >3 Vrms of headroom into 2 kohm ADC driver loads. The shutdown pin also enables power gating in portable audio recorders.
Recommended
Active Filter Block
The OPA632U's 68 MHz gain-bandwidth product and 100 V/us slew rate support Sallen-Key, multiple-feedback (MFB), and state-variable active filter topologies at cutoff frequencies up to 5 MHz. Unity-gain stability with capacitive loads up to 100 pF makes the part well suited for low-pass anti-aliasing filters feeding high-speed ADCs. The single-supply rail-includes-ground input range lets designers use ground-referenced source signals without level shifting, while the 6 mA quiescent current keeps thermal dissipation modest in dense filter banks.
Recommended
Photodiode Transimpedance Amplifier
For moderate-bandwidth photodiode front-ends, the OPA632U's 6 nV/sqrt(Hz) input voltage noise and 100 V/us slew rate allow transimpedance gains of 10-100 kohm with closed-loop bandwidths approaching 1 MHz. The bipolar input stage provides low input bias current for silicon PIN photodiodes, and the shutdown feature enables pulsed-light applications such as LIDAR receivers and time-of-flight sensors to gate the analog front-end between measurements, reducing average system power.
Recommended
Video Line Driver
The OPA632U drives 75 ohm video loads with 0.1 dB gain flatness up to 10 MHz and differential gain/phase below 0.05 percent/0.05 degree, making it suitable for composite video distribution and NTSC/PAL line-driving. The 4.8 V output swing on 5 V supply easily delivers 2 Vpp into a doubly-terminated 75 ohm line. Its single-supply 5 V operation also matches typical video ASIC environments without needing a -5 V rail, simplifying PCB layout.
Recommended
Portable Instrumentation Front-End
Battery-powered test and measurement instruments benefit from the OPA632U's 6 mA quiescent current, single 5 V supply operation, and shutdown feature that drops consumption below 1 uA. Its 68 MHz bandwidth supports 1 MHz-class sensor signal conditioning, and the 6 nV/sqrt(Hz) noise floor preserves the dynamic range of 16-18 bit SAR ADCs in handheld multimeters, data loggers, and field-portable oscilloscope probe amplifiers.
Recommended
Professional Audio Line Driver
Professional audio line drivers and headphone amplifiers benefit from the OPA632U's 0.02 percent THD+N at 1 kHz, 6 nV/sqrt(Hz) noise floor, and 100 V/us slew rate that keeps distortion low at high output amplitudes. The shutdown pin enables mute-on-idle in pro-audio mixers and broadcast consoles, while the SOIC-8 footprint simplifies board-level rework in densely populated audio signal paths where PCB real estate is at a premium.
Recommended
Recommended Products Summary
Engineering reference data for OPA632U — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | OPA634U | OPA627AU | LM358D | LM2904M | AD8055ARZ | MAX4450EUK+T |
|---|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices | Analog Devices (Maxim) |
| Package | 8-SOIC (D) | 8-SOIC (D) - same | 8-SOIC (D) - same | 8-SOIC (D) - same | 8-SOIC (D) - same | 8-SOIC (D) - same | 8-SOIC (D) - same |
| Bandwidth | 68 MHz | 100 MHz | 16 MHz | 1 MHz | 1 MHz | 300 MHz | 200 MHz |
| Slew Rate | 100 V/us | 100 V/us | 55 V/us | 0.3 V/us | 0.3 V/us | 1150 V/us | 485 V/us |
| Supply Current | 6 mA | 8 mA | 7 mA | 0.7 mA | 0.7 mA | 5.5 mA | 5.5 mA |
| Input Voltage Noise | 6 nV/sqrt(Hz) | 7 nV/sqrt(Hz) | 4.5 nV/sqrt(Hz) | 40 nV/sqrt(Hz) | 40 nV/sqrt(Hz) | 6 nV/sqrt(Hz) | 6 nV/sqrt(Hz) |
| Single-Supply Range | 2.5 V to 10 V | 2.5 V to 10 V | Dual +/-5 V to +/-18 V | 3 V to 32 V | 3 V to 32 V | 8 V to 12 V (dual +/-4 V to +/-6 V) | 2.7 V to 11 V |
| Shutdown Pin | Yes (SHDN) | Yes (SHDN) | No | No | No | No | No |
| Architecture | Voltage Feedback | Current Feedback | Voltage Feedback | Voltage Feedback | Voltage Feedback | Voltage Feedback | Voltage Feedback |
Key Differentiators
- Single-supply 5 V operation with ground-sensing input (vs OPA627AU)
- Higher bandwidth and slew rate than legacy dual op amps (vs LM358D)
- Integrated shutdown pin for power gating (vs AD8055ARZ)
Design Notes
Decouple the V+ pin with a 0.1 uF X7R ceramic capacitor placed within 5 mm of the IC, with an additional 10 uF tantalum or aluminum-polymer bulk capacitor for supply traces longer than 25 mm. For single-supply 5 V operation, connect V- directly to ground. The SHDN pin has an internal pull-down and should be tied to V+ through a 10 kohm resistor when shutdown is not used, to avoid floating-input noise and unintended enable cycling.
Estimated: at V+ = 5 V, V- = 0 V, 6 mA quiescent current, and SOIC-8 theta_JA of approximately 150 C/W, the OPA632U dissipates 30 mW and the junction temperature rises about 4.5 C above ambient. No heatsink is required. The shutdown feature reduces quiescent current below 1 uA, which is useful for battery-powered designs that need to extend operating time between charges. Continuous short-circuit current is internally limited to approximately +/-30 mA.
Use a ground plane on the layer directly beneath the SOIC-8 footprint and stitch the perimeter with vias on a 5 mm grid. Route input and feedback traces on the top layer to minimize parasitic capacitance, and keep the feedback resistor within 3 mm of the IN- pin. For driving 75 ohm video loads, place the back-termination resistor within 5 mm of the output pin to control transmission-line reflections above 10 MHz.
Do not apply input voltages that exceed the V+ rail or fall below the V- rail by more than 0.5 V, as the input ESD diodes will conduct and distort the signal. The SHDN pin must not be left floating - either drive it actively or pull it to V+ through a 10 kohm resistor. The output is not short-circuit-safe to ground indefinitely; observe the +/-30 mA internal current limit. Avoid capacitive loads above 200 pF without a 50-100 ohm series isolation resistor to prevent output peaking.
Compliance Information
OPA632U is RoHS-compliant and lead-free per Texas Instruments product page. Not AEC-Q100 qualified; for automotive-grade single-supply 5 V op amps consider the LM2904M automotive variant or the OPA4H014-EP. Manufactured in 8-SOIC JEDEC-standard package.
