Part A
AD812AR
テキサス・インスツルメンツ
- Lifecycle
- Active
- Stock
- 5743 個数
- Package
- SOIC-8
- Series
- リニアアンプ - ビデオアンプおよびモジュール
Replacement verdict
Compatible functional replacement candidate
The AD8129ARZ-REEL is a viable functional replacement candidate for the AD812AR in many differential receiver and line-driver applications, provided the designer validates the higher supply voltage range, the different package footprint, and the tighter gain-bandwidth and slew-rate characteristics against the target circuit requirements.
Supply Voltage Range
Validation required
Package Type
Validation required
Amplifier Function
High match
Bandwidth and Slew Rate
Validation required
Parts at a glance
Part B
AD8129ARZ-REEL
テキサス・インスツルメンツ
- Lifecycle
- Active
- Stock
- 151 個数
- Package
- SOIC-8
- Series
- リニアアンプ - 計装用、オペアンプ、バッファアンプ
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD812AR | AD8129ARZ-REEL | Why it matters |
|---|---|---|---|
| Number of Amplifiers | 2 (Dual) | 1 (Single) | Channel count determines whether the part can directly replace the other in multi-channel signal chains; a dual cannot be substituted by a single without redesign. |
| Amplifier Type / Function | Current Feedback (CFB) video op-amp | Low-noise voltage feedback differential receiver amplifier | The feedback topology and intended function differ fundamentally, so the two parts are not functionally interchangeable in most circuits. |
| -3 dB Bandwidth | 145 MHz (G = +2) | 200 MHz (G = +2) | Bandwidth sets the maximum signal frequency the amplifier can pass with acceptable gain, affecting high-speed signal fidelity. |
| Slew Rate | 1600 V/µs | 1100 V/µs | Slew rate limits how fast the output can respond to large signal steps; lower slew rate can distort fast transients. |
| Input Voltage Noise | ~3.5 nV/√Hz | ~4.5 nV/√Hz | Lower input noise improves signal-to-noise ratio in low-level signal applications, a key selection criterion. |
| Supply Voltage Range | ±2.5 V to ±15 V (dual supply) | ±5 V to ±12 V (dual supply) | The usable supply range must cover the system rails; a narrower range may prevent direct substitution in higher-voltage designs. |
| Supply Current per Amplifier | ~5.5 mA | ~6.5 mA | Quiescent current affects power budget and thermal design, especially in multi-channel or battery-powered systems. |
| Package | 8-lead SOIC (SOIC-8) | 8-lead SOIC (SOIC-8), tape and reel | Package and pinout compatibility determine whether the part can be dropped onto an existing PCB footprint; both share SOIC-8 but pin functions differ. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Matching temperature ratings ensures the replacement meets the same environmental operating requirements. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AD812AR | AD8129ARZ-REEL |
|---|---|---|
| Supplier | - | Analog Devices Inc.,Rochester Electronics, LLC |
| Part Status | Obsolete | Active |
| Amplifier Type | - | Differential |
| Number of Circuits | 2 | 1 |
| Slew Rate | 1600V/µs | 1070V/µs |
| -3 dB Bandwidth | 145 MHz | 200 MHz |
| Current - Input Bias | - | 500 nA |
| Voltage - Input Offset | - | 200 µV |
| Supply Current | 4.5 mA | 13mA |
| Current - Output / Channel | 50 mA | 40 mA |
| Voltage - Supply Span(Min) | - | 4.5 V |
| Voltage - Supply Span(Max) | - | 25.2 V |
| Operating Temperature | - | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
| Applications | Current Feedback | - |
| Voltage - Supply, Single/Dual (±) | 2.4V ~ 36V, ±1.2V ~ 18V | - |
Frequently asked questions
Are the AD812AR and AD8129ARZ-REEL interchangeable in an existing design?
No, they are not direct substitutes. The AD812AR is a dual, current-feedback operational amplifier in an 8-lead SOIC package, while the AD8129ARZ-REEL is a single, low-power, high-speed voltage-feedback amplifier in an 8-lead SOIC package. They differ in channel count, amplifier topology, pinout, and supply current, so a board redesign and full revalidation would be required.
What are the key differences in amplifier architecture between the AD812AR and AD8129ARZ-REEL?
The AD812AR is a dual current-feedback amplifier optimized for high slew rate and wide bandwidth at low gains, making it suited to video and high-speed signal processing. The AD8129ARZ-REEL is a single voltage-feedback amplifier designed for low power consumption and stable performance across a wide range of gains. The feedback topology difference affects gain-setting resistor selection and closed-loop bandwidth behavior.
How do the supply voltage and power consumption specifications compare?
The AD812AR operates on dual supplies typically from ±2.5 V to ±15 V and draws a higher quiescent current per amplifier due to its dual current-feedback design. The AD8129ARZ-REEL is specified for low-power operation with a lower quiescent supply current per amplifier, making it preferable for power-sensitive applications. Designers should consult the respective datasheets for exact quiescent current and supply range limits before finalizing a power budget.
Can the AD8129ARZ-REEL be used to replace one channel of the AD812AR in a dual-amplifier circuit?
Not directly. Although both are 8-lead SOIC devices, their pinouts and feedback architectures differ. The AD812AR pinout is arranged for two current-feedback amplifiers, whereas the AD8129ARZ-REEL pinout is configured for a single voltage-feedback amplifier with different pin functions. Substituting one channel would require PCB rework and verification of gain, stability, and bandwidth with the new topology.
Which part is better suited for video signal processing applications?
The AD812AR, with its dual current-feedback architecture, high slew rate, and wide bandwidth, is typically selected for video and high-speed analog signal chains where low gain and high dynamic performance are required. The AD8129ARZ-REEL, being a low-power voltage-feedback amplifier, is more appropriate for general-purpose, power-constrained signal conditioning rather than wideband video distribution.
Do the AD812AR and AD8129ARZ-REEL share the same package and PCB footprint?
Both devices are offered in an 8-lead SOIC package, so the physical footprint dimensions are similar. However, identical package outline does not imply pin compatibility. The pin assignments and internal connections differ between the dual current-feedback AD812AR and the single voltage-feedback AD8129ARZ-REEL, so the PCB land pattern may match while the circuit connections do not.
What should be verified before considering a design change from AD812AR to AD8129ARZ-REEL?
Verify channel count requirements, feedback topology, pinout, supply voltage range, quiescent current, gain-bandwidth product, slew rate, and output drive capability against the official manufacturer datasheets. Also confirm that the reduced channel count and different gain stability behavior of the voltage-feedback AD8129ARZ-REEL meet the application's signal chain requirements, and revalidate the PCB layout and compensation network accordingly.