Part A
ADA4891-2ARMZ
テキサス・インスツルメンツ
- Lifecycle
- Active
- Stock
- 6456 個数
- Series
- リニアアンプ - 計装用、オペアンプ、バッファアンプ
Replacement verdict
Compatible functional replacement candidate
The ADA4897-2ARMZ-RL is a viable functional replacement candidate for the ADA4891-2ARMZ in many designs, sharing the same dual-channel topology, MSOP-8 footprint, and wide supply range, though the ADA4897-2 offers substantially lower input bias current and lower voltage noise while consuming less quiescent current per amplifier. Designers should validate bandwidth, slew rate, and dynamic performance in the target application, since the two parts differ in their AC and transient characteristics.
Package Type
High match
Channel Count
High match
Supply Voltage Range
Validation required
Bandwidth and Slew Rate
Validation required
Parts at a glance
Part B
ADA4897-2ARMZ-RL
テキサス・インスツルメンツ
- Lifecycle
- Active
- Stock
- 4605 個数
- Package
- MSOP-10
- 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 | ADA4891-2ARMZ | ADA4897-2ARMZ-RL | Why it matters |
|---|---|---|---|
| Number of Amplifiers | 2 | 2 | Both are dual op-amps, so channel count is compatible for dual-channel signal chains. |
| -3 dB Bandwidth | 240 MHz | 230 MHz | Bandwidth determines the maximum signal frequency the amplifier can handle with acceptable gain roll-off. |
| Slew Rate | 170 V/µs | 120 V/µs | Slew rate limits how fast the output can respond to large signal steps; higher slew rate supports faster large-signal handling. |
| Input Voltage Noise Density | 9 nV/√Hz | 1 nV/√Hz | Lower input noise improves signal-to-noise ratio in precision and low-level signal applications. |
| Supply Voltage Range | 2.7 V to 5.5 V | 3 V to 10 V | The supply range must match the system rail voltages; the ADA4897 supports higher supply voltages than the ADA4891. |
| Quiescent Current (per amplifier) | 4.4 mA | 3 mA | Quiescent current affects power consumption and thermal budget, critical in portable and dense designs. |
| Input Offset Voltage (max) | 6 mV | 0.5 mV | Lower offset voltage reduces DC error, important for precision amplification and sensor interfaces. |
| Package | 8-Lead MSOP | 8-Lead MSOP | Package compatibility ensures the part can be placed on the same PCB footprint without layout changes. |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | Both cover the industrial temperature range, so environmental compatibility is equivalent. |
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 | ADA4891-2ARMZ | ADA4897-2ARMZ-RL |
|---|---|---|
| Supplier | - | Analog Devices Inc.,Rochester Electronics, LLC |
| Part Status | Active | Active |
| Amplifier Type | CMOS | Voltage Feedback |
| Number of Circuits | 2 | 2 |
| Output Type | Rail-to-Rail | Rail-to-Rail |
| Slew Rate | 210V/µs | 120V/µs |
| Gain Bandwidth Product | 105 MHz | 90 MHz |
| -3 dB Bandwidth | 90 MHz | 230 MHz |
| Current - Input Bias | 2 pA | 4 µA |
| Voltage - Input Offset | 2.5 mV | 28 µV |
| Supply Current | 4.4mA (x2 Channels) | 3mA (x2 Channels) |
| Current - Output / Channel | 125 mA | 80 mA |
| Voltage - Supply Span(Min) | 2.7 V | 3 V |
| Voltage - Supply Span(Max) | 5.5 V | 10 V |
| Operating Temperature | -40°C ~ 125°C | -40°C ~ 125°C |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the primary differences between the ADA4891-2ARMZ and the ADA4897-2ARMZ-RL?
The ADA4891-2ARMZ is a dual, low-cost, high-speed CMOS operational amplifier with a 220 MHz gain-bandwidth product and 170 V/µs slew rate, optimized for cost-sensitive video and signal processing applications. The ADA4897-2ARMZ-RL is a dual, low-noise, high-speed amplifier with a 230 MHz gain-bandwidth product, 1.2 nV/√Hz input voltage noise, and 120 V/µs slew rate, designed for precision instrumentation and low-noise signal chains. The ADA4897-2ARMZ-RL is supplied in tape-and-reel packaging (RL suffix), while the ADA4891-2ARMZ is supplied in standard tube or tray packaging.
Are the ADA4891-2ARMZ and ADA4897-2ARMZ-RL pin-compatible?
Yes. Both devices are offered in the same 8-lead MSOP (ARMZ) package and share the standard dual op-amp pinout: pin 1 = OUT A, pin 2 = -IN A, pin 3 = +IN A, pin 4 = V-, pin 5 = +IN B, pin 6 = -IN B, pin 7 = OUT B, and pin 8 = V+. This allows them to be used on the same PCB land pattern, though electrical performance differences must be evaluated for the target design.
Which device is better suited for low-noise precision applications?
The ADA4897-2ARMZ-RL is better suited for low-noise precision applications. Its input voltage noise density is 1.2 nV/√Hz at 100 kHz, compared to the ADA4891-2ARMZ, which has a higher input voltage noise density (typically 12 nV/√Hz at 1 MHz per the datasheet). The ADA4897-2 also offers lower offset voltage and higher DC precision, making it preferable for instrumentation and sensor interface designs.
How do the gain-bandwidth products of these two amplifiers compare?
The ADA4891-2ARMZ has a gain-bandwidth product of 220 MHz, while the ADA4897-2ARMZ-RL has a gain-bandwidth product of 230 MHz. The values are close, but the ADA4897-2 provides additional headroom for high-frequency signal processing while maintaining lower noise.
What are the slew rate specifications for each device?
The ADA4891-2ARMZ has a slew rate of 170 V/µs, and the ADA4897-2ARMZ-RL has a slew rate of 120 V/µs. The ADA4891-2 offers a higher slew rate, which can be advantageous in pulse and video applications requiring fast large-signal transitions.
Do both devices support the same supply voltage range?
Both devices operate from a single supply of 3 V to 10 V or a dual supply of ±1.5 V to ±5 V. This overlapping supply range allows either part to be used in many common signal-chain designs, but the user must verify that noise, bandwidth, and output swing requirements are met for the specific application.
What does the "RL" suffix on the ADA4897-2ARMZ-RL indicate?
The "RL" suffix indicates tape-and-reel packaging, which is intended for high-volume automated assembly. The ADA4891-2ARMZ without the RL suffix is typically supplied in standard tube or tray packaging. The electrical specifications of the device are the same regardless of packaging suffix.
Can the ADA4891-2ARMZ be used as a drop-in replacement for the ADA4897-2ARMZ-RL?
Because both parts share the same 8-lead MSOP pinout, a drop-in replacement is physically possible. However, a direct substitution is not recommended without validation, since the ADA4891-2 has higher input noise and different AC/DC characteristics than the ADA4897-2. The designer must confirm that noise, offset, bandwidth, and slew-rate requirements of the target circuit are satisfied by the ADA4891-2ARMZ before replacing the ADA4897-2ARMZ-RL.