Part A
AD8599ARZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 5652 PCS
- Package
- SOIC-8
- Series
- Linear - Amplificadores - Instrumentação, OP Amps, Buffer Amps
Replacement verdict
Compatible functional replacement candidate
The AD8599ARZ and AD8594AR are both dual, low-noise operational amplifiers from Analog Devices, making the AD8599ARZ a viable functional replacement candidate for the AD8594AR in many dual-op-amp signal-conditioning applications. However, the AD8599ARZ offers substantially higher slew rate and wider gain bandwidth, so designers should validate stability, power consumption, and noise performance in the target circuit before committing to a drop-in substitution.
Channel Count
High match
Package Type
High match
Supply Voltage Range
Validation required
Gain Bandwidth Product
Validation required
Parts at a glance
Part B
AD8594AR
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 7427 PCS
- Package
- SOIC-16
- 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 | AD8599ARZ | AD8594AR | Why it matters |
|---|---|---|---|
| Number of Amplifiers | 2 (Dual) | 4 (Quad) | Channel count determines whether the part can drop into a given PCB footprint and circuit topology; a dual cannot directly replace a quad. |
| Input Voltage Noise Density | 1.07 nV/√Hz (typ) | 6 nV/√Hz (typ) | Lower noise density is critical for low-level signal amplification; the AD8599 is significantly quieter, affecting SNR in precision applications. |
| Gain Bandwidth Product | 10 MHz (typ) | 3 MHz (typ) | GBP sets the achievable closed-loop bandwidth and stability; a lower GBP part may not meet high-frequency signal requirements. |
| Slew Rate | 16 V/µs (typ) | 5 V/µs (typ) | Slew rate limits large-signal bandwidth and transient response; the faster AD8599 handles faster signal edges. |
| Input Offset Voltage | 10 µV (max) | 500 µV (max) | Offset voltage directly adds DC error; the much lower offset of the AD8599 is important for precision DC-coupled designs. |
| Supply Current per Amplifier | ~2.5 mA (typ) | ~1.4 mA (typ) | Quiescent current affects power budget and thermal design; the quad AD8594 draws less per amplifier. |
| Package | 8-Lead SOIC | 14-Lead SOIC | Package and pin count must match the board layout; different footprints prevent direct physical substitution. |
| Supply Voltage Range | ±5 V to ±15 V (dual supply) | ±2.5 V to ±15 V (dual supply) | The usable supply range determines compatibility with the system rails; the AD8594 supports lower-voltage operation. |
| Total Harmonic Distortion | 0.0003% (typ) | 0.0005% (typ) | THD indicates signal fidelity for audio and precision AC applications; lower distortion preserves signal purity. |
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 | AD8599ARZ | AD8594AR |
|---|---|---|
| Supplier | - | Rochester Electronics, LLC |
| Part Status | Active | Obsolete |
| Amplifier Type | General Purpose | General Purpose |
| Number of Circuits | 2 | 4 |
| Output Type | - | Rail-to-Rail |
| Slew Rate | 16V/µs | 5V/µs |
| Gain Bandwidth Product | 10 MHz | 3 MHz |
| Current - Input Bias | 25 nA | 5 pA |
| Voltage - Input Offset | 10 µV | 2 mV |
| Current - Output / Channel | 52 mA | 250 mA |
| Voltage - Supply Span(Min) | 9 V | 2.5 V |
| Voltage - Supply Span(Max) | 30 V | 6 V |
| Operating Temperature | -40°C ~ 125°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
| Supply Current | 5mA (x2 Channels) | - |
Frequently asked questions
What are the key differences between the AD8599ARZ and AD8594AR?
The AD8599ARZ is a dual, ultralow-noise, low-distortion operational amplifier specified for ±5 V to ±15 V dual supplies, while the AD8594AR is a quad, low-noise, rail-to-rail output op amp specified for 2.7 V to 12 V single supply (or ±1.35 V to ±6 V dual supply). The AD8599ARZ offers lower voltage noise (approximately 1 nV/√Hz) than the AD8594AR (approximately 8 nV/√Hz), but the AD8594AR provides four amplifiers per package with rail-to-rail output swing.
Are the AD8599ARZ and AD8594AR pin-compatible?
No. The AD8599ARZ is a dual op amp in an 8-lead SOIC package, while the AD8594AR is a quad op amp in a 14-lead SOIC package. They have different pin counts and pinouts, so they are not drop-in replacements for each other.
What are the supply voltage ranges for the AD8599ARZ and AD8594AR?
The AD8599ARZ operates from ±5 V to ±15 V dual supplies (10 V to 30 V total). The AD8594AR operates from 2.7 V to 12 V single supply or ±1.35 V to ±6 V dual supply.
How does the voltage noise of the AD8599ARZ compare with the AD8594AR?
The AD8599ARZ is specified with a typical voltage noise density of approximately 1 nV/√Hz at 1 kHz, making it suitable for ultralow-noise applications. The AD8594AR has a typical voltage noise density of approximately 8 nV/√Hz at 1 kHz, which is higher but still suitable for many general-purpose low-noise designs.
Can the AD8594AR be used in a single-supply application where the AD8599ARZ cannot?
Yes. The AD8594AR is specified for single-supply operation from 2.7 V to 12 V and features rail-to-rail output swing, making it suitable for low-voltage single-supply systems. The AD8599ARZ is specified for dual supplies of ±5 V to ±15 V and is not characterized for single-supply operation at low voltages.
Which device is better suited for a quad-channel low-noise signal chain?
The AD8594AR integrates four amplifiers in a single 14-lead SOIC package, reducing board space for multi-channel designs. However, if ultralow noise is the priority, the AD8599ARZ offers significantly lower voltage noise but provides only two amplifiers per package, so two devices would be required for four channels.
Do both the AD8599ARZ and AD8594AR support rail-to-rail output?
The AD8594AR features rail-to-rail output swing, allowing the output to swing close to both supply rails. The AD8599ARZ is not specified as a rail-to-rail output device; its output swing is characterized relative to its dual-supply operating conditions per the manufacturer datasheet.