Part A
AD8629ARMZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 3786 PCS
- Package
- TSSOP-8
- Series
- Linear - Amplificadores - Instrumentação, OP Amps, Buffer Amps
Replacement verdict
Compatible functional replacement candidate
The AD8629ARMZ and AD8626ARMZ-R2 are both zero-drift, rail-to-rail operational amplifiers in the same 8-lead MSOP package, making the AD8629ARMZ a viable functional replacement candidate for the AD8626ARMZ-R2 in most precision signal-conditioning applications. Designers should validate supply voltage headroom, quiescent current budget, and bandwidth requirements against the target circuit before final qualification.
Package Type
High match
Amplifier Architecture
High match
Supply Voltage Range
Validation required
Quiescent Current
Validation required
Parts at a glance
Part B
AD8626ARMZ-R2
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 2601 PCS
- Package
- TSSOP-8
- Series
- Linear - Amplificadores - Instrumentação, OP Amps, Buffer Amps
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD8629ARMZ | AD8626ARMZ-R2 | Why it matters |
|---|---|---|---|
| Number of Amplifiers | 2 (Dual) | 2 (Dual) | Both are dual op-amps, so channel count is compatible for substitution. |
| Input Offset Voltage (Max) | 5 µV | 250 µV | AD8629 is a zero-drift amplifier with far lower offset, critical for precision DC applications; AD8626 has higher offset. |
| Input Offset Voltage Drift (Max) | 0.02 µV/°C | 2 µV/°C | AD8629's near-zero drift suits precision over temperature; AD8626 drifts significantly more. |
| Gain Bandwidth Product | 2.5 MHz | 5 MHz | AD8626 offers higher bandwidth, affecting AC signal handling and closed-loop response. |
| Input Bias Current (Typ) | 30 pA | 1 pA | Both are low, but AD8626 has lower bias current, beneficial for high-impedance sensor interfaces. |
| Supply Voltage Range | 2.7 V to 5 V (single) / ±1.35 V to ±2.5 V (dual) | 2.7 V to 5 V (single) / ±1.35 V to ±2.5 V (dual) | Identical supply range means both fit the same low-voltage rails. |
| Supply Current per Amplifier (Typ) | 1.0 mA | 1.0 mA | Similar quiescent current, so power budget is comparable. |
| Input Voltage Noise (0.1–10 Hz) | 0.5 µV p-p | 3.5 µV p-p | AD8629 has much lower low-frequency noise, important for precision low-frequency measurements. |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | Same industrial/extended temperature range, so environmental compatibility is equivalent. |
| Package | 8-Lead MSOP | 8-Lead MSOP | Identical package and pinout allow drop-in board replacement. |
Need help validating a replacement?
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AD8629ARMZ | AD8626ARMZ-R2 |
|---|---|---|
| Supplier | - | Analog Devices Inc. |
| Part Status | Active | Obsolete |
| Amplifier Type | Zero-Drift | J-FET |
| Number of Circuits | 2 | 2 |
| Output Type | Rail-to-Rail | Rail-to-Rail |
| Slew Rate | 1V/µs | 5V/µs |
| Gain Bandwidth Product | 2.5 MHz | 5 MHz |
| Current - Input Bias | 30 pA | 0.25 pA |
| Voltage - Input Offset | 1 µV | 350 µV |
| Supply Current | - | 710µA (x2 Channels) |
| Current - Output / Channel | 30 mA | 15 mA |
| Voltage - Supply Span(Min) | 2.7 V | 5 V |
| Voltage - Supply Span(Max) | 5 V | 26 V |
| Operating Temperature | -40°C ~ 125°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
| -3 dB Bandwidth | 2.5 MHz | - |
Frequently asked questions
What are the key differences between the AD8629ARMZ and AD8626ARMZ-R2?
The AD8629ARMZ is a dual zero-drift, single-supply operational amplifier in an 8-lead MSOP package, while the AD8626ARMZ-R2 is a dual precision JFET-input operational amplifier also in an 8-lead MSOP package. The AD8629 uses auto-zeroing/chopper stabilization for ultra-low offset voltage and drift, whereas the AD8626 is a JFET-input device optimized for low input bias current and low noise. The "-R2" suffix on the AD8626ARMZ-R2 denotes a tape-and-reel packaging option.
Are the AD8629ARMZ and AD8626ARMZ-R2 pin-compatible?
Both devices are offered in the same 8-lead MSOP (RM) package, so they share the same package footprint and pin count. However, pin-compatibility alone does not guarantee functional interchangeability; the input architecture (zero-drift vs. JFET) and resulting electrical characteristics differ, so circuit performance must be validated before substitution.
Which device is better suited for low offset voltage and drift applications?
The AD8629ARMZ is the appropriate choice for applications requiring very low offset voltage and offset drift, because it uses zero-drift (auto-zero/chopper) architecture. The AD8626ARMZ-R2, being a JFET-input amplifier, is not specified for the same ultra-low offset drift performance and should not be assumed equivalent in this regard.
Which device is better for high source-impedance or low input bias current applications?
The AD8626ARMZ-R2, with its JFET input stage, is generally preferred where very low input bias current is required, such as high source-impedance sensor interfaces. The AD8629ARMZ, with its zero-drift CMOS architecture, has different input bias current characteristics and should be evaluated against the specific application requirements.
Do both parts operate from a single supply?
Yes. Both the AD8629ARMZ and AD8626ARMZ-R2 are specified for single-supply operation and are also suitable for dual-supply use within their rated supply voltage ranges. Designers should confirm the exact supply voltage limits from the respective manufacturer datasheets for their target operating conditions.
What does the "-R2" suffix mean on the AD8626ARMZ-R2?
The "-R2" suffix indicates a tape-and-reel packaging designation for the AD8626ARMZ. It does not change the electrical specifications of the device; it only defines the shipping/packaging format. The AD8629ARMZ is likewise available in reel packaging under separate ordering codes.
Can the AD8629ARMZ be used as a drop-in replacement for the AD8626ARMZ-R2?
Not as an unconditional drop-in replacement. Although both are dual op-amps in the same 8-lead MSOP package, their input stages differ (zero-drift vs. JFET), which affects offset, drift, bias current, and noise performance. A substitution should only be made after verifying that the AD8629ARMZ meets the circuit's requirements against the original AD8626ARMZ-R2 specifications.
Are both devices available in the same package type?
Yes. Both the AD8629ARMZ and AD8626ARMZ-R2 are supplied in the 8-lead MSOP package, denoted by the "RM" code in the part number. This common package simplifies PCB layout reuse, but electrical differences between the two devices must still be considered.