Part A
ADA4665-2ARMZ
아날로그 디바이스(주)
- Lifecycle
- Active
- Stock
- 3904 PCS
- Series
- 선형 증폭기 - 계측기, 연산 증폭기, 완충 증폭기
Replacement verdict
Compatible functional replacement candidate
The ADA4661-2ARMZ and ADA4665-2ARMZ are both dual low-power CMOS operational amplifiers in the same 8-lead MSOP package, making the ADA4661-2ARMZ a viable functional replacement candidate for the ADA4665-2ARMZ in many designs. However, the two devices differ in supply voltage range, quiescent current, and gain-bandwidth product, so the replacement should be validated against the target application's power budget and AC performance requirements before adoption.
Package Type
High match
Channel Count
High match
Supply Voltage Range
Validation required
Quiescent Current
Validation required
Parts at a glance
Part B
ADA4661-2ARMZ
아날로그 디바이스(주)
- Lifecycle
- Active
- Stock
- 2207 PCS
- Series
- 선형 증폭기 - 계측기, 연산 증폭기, 완충 증폭기
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADA4661-2ARMZ | ADA4665-2ARMZ | Why it matters |
|---|---|---|---|
| Number of Amplifiers | 2 | 2 | Both are dual op-amps, so channel count is compatible for direct substitution in dual-channel circuits. |
| Supply Voltage Range | 4 V to 18 V | 2.7 V to 12 V | The wider supply range of the ADA4661-2ARMZ allows operation at higher rails, while the ADA4665-2ARMZ supports lower supply voltages; this affects compatibility in low-voltage and high-voltage systems. |
| Input Offset Voltage (Max) | 0.15 mV | 1 mV | Lower offset voltage improves DC precision; the ADA4661-2ARMZ offers significantly better offset performance for precision signal chains. |
| Input Bias Current (Typ) | 1 pA | 1 pA | Very low input bias current is critical for high-impedance sensor interfaces; both parts are comparable here. |
| Gain Bandwidth Product | 4 MHz | 1.2 MHz | Higher gain bandwidth enables wider signal bandwidth and faster settling; the ADA4661-2ARMZ supports higher-frequency applications than the ADA4665-2ARMZ. |
| Slew Rate | 2 V/µs | 0.9 V/µs | Slew rate limits large-signal dynamic response; the ADA4661-2ARMZ handles faster transients and larger signal swings. |
| Supply Current per Amplifier (Typ) | 630 µA | 145 µA | Lower quiescent current benefits battery-powered and power-sensitive designs; the ADA4665-2ARMZ is significantly more power-efficient. |
| Input Voltage Noise Density (1 kHz) | 22 nV/√Hz | 22 nV/√Hz | Noise density affects SNR in low-level signal amplification; both parts offer comparable noise performance. |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | Identical industrial temperature ranges ensure both parts are suitable for the same environmental conditions. |
| Package | 8-Lead MSOP | 8-Lead MSOP | Matching package and pinout allow drop-in replacement on the same PCB footprint. |
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 | ADA4665-2ARMZ | ADA4661-2ARMZ |
|---|---|---|
| Part Status | Active | Active |
| Amplifier Type | CMOS | CMOS |
| Number of Circuits | 2 | 2 |
| Output Type | Rail-to-Rail | Rail-to-Rail |
| Slew Rate | 1V/µs | 2V/µs |
| Gain Bandwidth Product | 1.2 MHz | 4 MHz |
| Current - Input Bias | 0.1 pA | 0.5 pA |
| Voltage - Input Offset | 1 mV | 30 µV |
| Supply Current | 290µA (x2 Channels) | 630µA (x2 Channels) |
| Current - Output / Channel | 30 mA | 220 mA |
| Voltage - Supply Span(Min) | 5 V | 3 V |
| Voltage - Supply Span(Max) | 16 V | 18 V |
| Operating Temperature | -40°C ~ 125°C | -40°C ~ 125°C |
| Mounting Type | Surface Mount | Surface Mount |
| -3 dB Bandwidth | - | 2.1 MHz |
Frequently asked questions
What are the key differences between the ADA4661-2ARMZ and ADA4665-2ARMZ operational amplifiers?
Both are dual, precision, low-power CMOS operational amplifiers from Analog Devices in an 8-lead MSOP (RM) package. The ADA4661-2 is a higher-bandwidth, lower-noise part with a typical gain bandwidth product of 4 MHz and a typical voltage noise density of 22 nV/√Hz, while the ADA4665-2 offers a lower typical GBW of 1.2 MHz with a typical voltage noise density of 22 nV/√Hz. The ADA4661-2 is generally specified for higher supply voltage operation (up to 18 V) and lower input bias current, whereas the ADA4665-2 is optimized for lower power consumption per amplifier.
Are the ADA4661-2ARMZ and ADA4665-2ARMZ pin-compatible?
Yes. Both devices are offered in the same 8-lead MSOP package (RM suffix) with the same pinout: OUT A, -IN A, +IN A, V-, +IN B, -IN B, OUT B, and V+. This allows them to share a common PCB footprint, but electrical differences must still be validated before substitution.
What is the supply voltage range for each device?
The ADA4661-2 is specified for operation from 2.7 V to 18 V (single supply) or ±1.35 V to ±9 V (dual supply). The ADA4665-2 is specified for operation from 2.7 V to 5.5 V (single supply) or ±1.35 V to ±2.75 V (dual supply). Designs operating above 5.5 V total supply must use the ADA4661-2.
How do the quiescent supply currents compare?
The ADA4665-2 is optimized for low power, with a typical supply current of approximately 145 µA per amplifier. The ADA4661-2 draws a higher typical supply current of approximately 630 µA per amplifier, reflecting its higher bandwidth. Total system power budgets should be recalculated when substituting between the two.
Which device offers better AC performance for signal conditioning?
The ADA4661-2 provides higher AC performance, with a typical gain bandwidth product of 4 MHz and a typical slew rate of 2 V/µs, compared with approximately 1.2 MHz GBW and 0.6 V/µs slew rate for the ADA4665-2. For higher-frequency signal chains, the ADA4661-2 is the appropriate choice, provided the supply voltage and power budget allow it.
Can the ADA4665-2ARMZ be used as a drop-in replacement for the ADA4661-2ARMZ?
Not unconditionally. Although the package and pinout match, the ADA4665-2 has a lower maximum supply voltage (5.5 V versus 18 V), lower bandwidth, and different input bias current and noise specifications. A drop-in replacement is only valid if the target design operates within the ADA4665-2's supply range and its reduced AC performance meets the application requirements, as confirmed against the respective datasheets.
What are the input bias current specifications for these amplifiers?
Both are CMOS-input amplifiers with very low input bias current. The ADA4661-2 is specified with a typical input bias current of approximately 1 pA at room temperature, while the ADA4665-2 is specified with a typical input bias current of approximately 1 pA as well. For high-impedance sensor interfaces, both devices are suitable, but the full over-temperature specification should be reviewed in the datasheets.