Part A
AD8651ARMZ
Analog Equipment GmbH.
- Lifecycle
- Active
- Stock
- 6670 PCS
- Package
- MSOP-8
- Series
- Amplificateurs linéaires - instruments, amplificateurs opérationnels, amplificateurs tampons
Replacement verdict
Compatible functional replacement candidate
The AD8657ARMZ-RL is a viable functional replacement candidate for the AD8651ARMZ in low-voltage, low-power precision signal-chain designs, as both share the same MSOP-8 footprint, CMOS rail-to-rail input/output architecture, and single-supply operating range. Designers should validate bandwidth, quiescent current, and noise performance against the specific application requirements before committing to a drop-in substitution.
Package Type
High match
Supply Voltage Range
Validation required
Gain Bandwidth Product
Not compatible
Quiescent Current
Validation required
Parts at a glance
Part B
AD8657ARMZ-RL
Analog Equipment GmbH.
- Lifecycle
- Active
- Stock
- 8479 PCS
- Package
- TSSOP-8
- Series
- Amplificateurs linéaires - instruments, amplificateurs opérationnels, amplificateurs tampons
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD8651ARMZ | AD8657ARMZ-RL | Why it matters |
|---|---|---|---|
| Number of Amplifiers | 1 | 2 | Determines how many independent signal channels are available in a single package; a dual op-amp can replace two singles but not vice versa. |
| Input Offset Voltage (Max) | 250 µV | 350 µV | Lower offset improves DC accuracy in precision signal-conditioning and sensor-interface circuits. |
| Input Bias Current (Typ) | 1 pA | 0.5 pA | Very low bias current minimizes errors in high-impedance and photodiode/transimpedance applications. |
| Gain Bandwidth Product | 50 MHz | 2.4 MHz | GBW sets the achievable closed-loop bandwidth and small-signal speed; a large difference affects high-frequency signal handling. |
| Slew Rate | 41 V/µs | 1.2 V/µs | Slew rate limits large-signal response and distortion; critical for fast transient and high-frequency designs. |
| Supply Current per Amplifier (Typ) | 9.5 mA | 0.9 mA | Quiescent current drives power budget and thermal design, especially in battery-powered or dense multi-channel systems. |
| Input Voltage Noise Density (Typ) | 5 nV/√Hz | 22 nV/√Hz | Lower noise density improves SNR in low-level signal amplification and precision measurement front ends. |
| Supply Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | Defines compatibility with single-supply rails; identical range supports drop-in supply compatibility. |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | Confirms both parts meet the same industrial temperature envelope for harsh-environment use. |
| Package | 8-Lead MSOP | 8-Lead MSOP | Same footprint and pin count enable PCB layout compatibility, though pinout functions differ between single and dual devices. |
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 | AD8651ARMZ | AD8657ARMZ-RL |
|---|---|---|
| Supplier | - | Analog Devices Inc. |
| Part Status | Active | Active |
| Amplifier Type | Voltage Feedback | CMOS |
| Number of Circuits | 1 | 2 |
| Output Type | Rail-to-Rail | Rail-to-Rail |
| Slew Rate | 41V/µs | 0.08V/µs |
| Gain Bandwidth Product | 50 MHz | 200 kHz |
| -3 dB Bandwidth | - | 305 kHz |
| Current - Input Bias | 1 pA | 5 pA |
| Voltage - Input Offset | 100 µV | 350 µV |
| Supply Current | 9.5mA | 18µA (x2 Channels) |
| Current - Output / Channel | 40 mA | 12 mA |
| Voltage - Supply Span(Min) | 2.7 V | 2.7 V |
| Voltage - Supply Span(Max) | 5.5 V | 18 V |
| Operating Temperature | -40°C ~ 125°C | -40°C ~ 125°C |
| Mounting Type | Surface Mount | Surface Mount |
| Series | DigiTrim® | - |
Frequently asked questions
What are the primary differences between the AD8651ARMZ and AD8657ARMZ-RL?
The AD8651ARMZ is a single-channel, 50 MHz rail-to-rail input/output CMOS operational amplifier optimized for low noise (5 nV/√Hz) and high speed. The AD8657ARMZ-RL is a dual-channel, 2.7 MHz rail-to-rail input/output CMOS operational amplifier optimized for low power (22 µA per amplifier) and precision DC performance. They differ in channel count, bandwidth, supply current, and target application profile.
Are the AD8651ARMZ and AD8657ARMZ-RL pin-compatible?
No. The AD8651ARMZ is a single op amp in an 8-lead MSOP package, while the AD8657ARMZ-RL is a dual op amp in an 8-lead MSOP package. Although both use the same package outline, the pin functions differ because one device is single-channel and the other is dual-channel. They are not direct drop-in replacements for each other.
What are the supply voltage ranges for these two amplifiers?
Both the AD8651ARMZ and AD8657ARMZ-RL operate from a single supply of 2.7 V to 5.5 V. This makes both devices suitable for low-voltage portable and battery-powered systems, though their current consumption and bandwidth characteristics differ significantly.
How do the quiescent supply currents compare between the AD8651ARMZ and AD8657ARMZ-RL?
The AD8651ARMZ typically draws about 8 mA per amplifier, reflecting its high-speed 50 MHz design. The AD8657ARMZ-RL typically draws only about 22 µA per amplifier, making it far better suited to ultra-low-power applications. This is one of the most significant selection criteria between the two parts.
Which device is better for low-noise signal conditioning?
The AD8651ARMZ is the better choice for low-noise signal conditioning, with a typical input voltage noise density of 5 nV/√Hz at 1 kHz. The AD8657ARMZ-RL has higher voltage noise and is optimized for low power and precision DC accuracy rather than low-noise AC performance. Designers should select based on whether noise or power consumption is the dominant constraint.
What are the gain-bandwidth products of the AD8651ARMZ and AD8657ARMZ-RL?
The AD8651ARMZ has a gain-bandwidth product of 50 MHz, supporting high-speed signal processing and fast settling. The AD8657ARMZ-RL has a gain-bandwidth product of 2.7 MHz, which is adequate for low-frequency precision and low-power sensor interfaces. The bandwidth difference is roughly a factor of 18 between the two devices.
Can the AD8657ARMZ-RL replace the AD8651ARMZ in an existing high-speed design?
No, not without redesign. The AD8657ARMZ-RL has a much lower gain-bandwidth product (2.7 MHz vs. 50 MHz) and lower slew rate than the AD8651ARMZ, so it cannot support the same high-speed signal chain. Additionally, the pinout differs because the AD8657ARMZ-RL is a dual device. A direct substitution is not technically valid.
What package options are available for the AD8651ARMZ and AD8657ARMZ-RL?
Both devices are offered in 8-lead MSOP (Mini Small Outline Package) variants. The AD8651ARMZ is a single op amp in an 8-lead MSOP, and the AD8657ARMZ-RL is a dual op amp in an 8-lead MSOP supplied in tape-and-reel format (indicated by the -RL suffix). Designers should confirm the exact package and ordering suffix against the respective manufacturer datasheets before layout.