Part A
AD8646ARZ
Analog Equipment GmbH.
- Lifecycle
- Active
- Stock
- 5091 PCS
- Package
- SOIC-8
- Series
- Amplificateurs linéaires - instruments, amplificateurs opérationnels, amplificateurs tampons
Replacement verdict
Compatible functional replacement candidate
The AD8648ARZ and AD8646ARZ are both quad-channel, low-power, rail-to-rail input/output operational amplifiers from Analog Devices in the same 14-lead SOIC package, sharing identical pinout and supply voltage range. The AD8648ARZ offers higher gain bandwidth and faster slew rate, making it a viable functional upgrade for the AD8646ARZ in most signal-conditioning applications, provided the designer validates bandwidth-dependent loop stability and capacitive load behavior.
Package Type
High match
Channel Count
High match
Supply Voltage Range
High match
Gain Bandwidth Product
Validation required
Parts at a glance
Part B
AD8648ARZ
Analog Equipment GmbH.
- Lifecycle
- Active
- Stock
- 5772 PCS
- Package
- SOIC-14
- 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 | AD8648ARZ | AD8646ARZ | Why it matters |
|---|---|---|---|
| Number of Amplifiers | 4 (Quad) | 2 (Dual) | Channel count determines how many independent signal paths can be processed; a quad and a dual are not directly interchangeable in multi-channel designs. |
| Gain Bandwidth Product | 24 MHz | 24 MHz | GBW sets the maximum usable frequency for small-signal amplification; matching values indicate similar AC performance. |
| Slew Rate | 11 V/µs | 11 V/µs | Slew rate limits large-signal bandwidth and transient response; identical values mean comparable dynamic behavior. |
| Input Offset Voltage (Max) | 2.5 mV | 2.5 mV | Offset voltage affects DC accuracy; equal maximums indicate similar precision in low-frequency signal chains. |
| Input Bias Current (Typ) | 0.3 pA | 0.3 pA | Very low bias current suits high-impedance sensor interfaces; matching values preserve input loading characteristics. |
| Supply Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | Compatible supply range ensures both parts operate in the same single-supply systems without level shifting. |
| Supply Current per Amplifier (Typ) | 0.8 mA | 0.8 mA | Quiescent current impacts power budget; equal per-amplifier draw means similar efficiency per channel. |
| Input Voltage Noise Density | 8 nV/√Hz | 8 nV/√Hz | Noise density governs SNR in low-level signal applications; identical values indicate equivalent noise performance. |
| Package | 14-Lead SOIC | 8-Lead SOIC | Different package footprints and pin counts prevent direct board-level substitution without layout changes. |
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 | AD8646ARZ | AD8648ARZ |
|---|---|---|
| Part Status | Active | Active |
| Amplifier Type | General Purpose | General Purpose |
| Number of Circuits | 2 | 4 |
| Output Type | Rail-to-Rail | Rail-to-Rail |
| Slew Rate | 11V/µs | 11V/µs |
| Gain Bandwidth Product | 24 MHz | 24 MHz |
| Current - Input Bias | 0.3 pA | 0.3 pA |
| Voltage - Input Offset | 600 µV | 600 µV |
| Supply Current | 1.5mA (x2 Channels) | 1.5mA (x4 Channels) |
| Current - Output / Channel | 120 mA | 120 mA |
| Voltage - Supply Span(Min) | 2.7 V | 2.7 V |
| Voltage - Supply Span(Max) | 5.5 V | 5.5 V |
| Operating Temperature | -40°C ~ 125°C | -40°C ~ 125°C |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the key differences between the AD8648ARZ and AD8646ARZ?
The AD8648ARZ is a quad-channel operational amplifier, while the AD8646ARZ is a dual-channel operational amplifier. Both are members of the Analog Devices AD8646/AD8647/AD8648 family of low noise, rail-to-rail input/output CMOS op amps, but they differ in channel count and package pinout. The AD8648ARZ is supplied in a 14-lead SOIC package, and the AD8646ARZ is supplied in an 8-lead SOIC package.
Are the AD8648ARZ and AD8646ARZ pin-compatible?
No. The AD8648ARZ uses a 14-lead SOIC package with four amplifiers, while the AD8646ARZ uses an 8-lead SOIC package with two amplifiers. The package body size and pin count differ, so they are not drop-in replacements for each other and require different PCB footprints.
Do the AD8648ARZ and AD8646ARZ share the same electrical performance per amplifier?
Yes. Both devices are part of the same AD8646/AD8647/AD8648 family and share the same core amplifier design, including low noise, rail-to-rail input and output, and CMOS input characteristics. Per-amplifier AC and DC specifications are common across the family, with the primary differences being channel count and package.
What supply voltage range do the AD8648ARZ and AD8646ARZ support?
Both devices operate from a single supply of 2.7 V to 5.5 V, or from dual supplies of ±1.35 V to ±2.75 V, as specified in the Analog Devices datasheet for the AD8646/AD8647/AD8648 family.
Are the AD8648ARZ and AD8646ARZ rail-to-rail input and output amplifiers?
Yes. Both the AD8648ARZ and AD8646ARZ feature rail-to-rail input and output swing, allowing signal operation close to both supply rails, which is beneficial in low-voltage single-supply designs.
What are typical applications for the AD8648ARZ versus the AD8646ARZ?
The AD8648ARZ (quad) is suited to multi-channel signal conditioning, active filtering, and sensor interface designs where four amplifiers are needed in one package. The AD8646ARZ (dual) is suited to compact two-channel designs such as portable instrumentation and audio signal paths where board space is limited.
Can the AD8646ARZ be used as a substitute for the AD8648ARZ in an existing design?
Not directly. Because the AD8648ARZ is a quad device in a 14-lead SOIC and the AD8646ARZ is a dual device in an 8-lead SOIC, substitution requires a PCB redesign to accommodate the different package, pin count, and channel count. Electrical per-amplifier performance is shared across the family, but the physical and channel-count differences prevent a direct drop-in replacement.