Part A
AD8422BRZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 3871 PCS
- Package
- SOIC-8
- Series
- Linear - Amplificadores - Instrumentação, OP Amps, Buffer Amps
Replacement verdict
Compatible functional replacement candidate
The AD8422ARZ-RL is a functionally compatible candidate for the AD8422BRZ, sharing the same amplifier architecture, pinout, package, and supply range, with the primary distinction being the grade-level specification for gain error and offset voltage. Designers should validate the relaxed DC precision tolerances of the ARZ grade against the tighter B-grade limits before substituting in precision instrumentation signal chains.
Package Type
High match
Pin Configuration
High match
Supply Voltage Range
High match
DC Precision Grade
Validation required
Parts at a glance
Part B
AD8422ARZ-RL
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 9390 PCS
- Package
- SOIC-8
- 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 | AD8422BRZ | AD8422ARZ-RL | Why it matters |
|---|---|---|---|
| Grade / Performance Class | B grade | A grade | The B grade is a higher-precision bin than the A grade, so key DC specs (offset, drift, gain error) are tighter; this affects accuracy-critical designs. |
| Input Offset Voltage (max) | ±60 µV (B grade) | ±150 µV (A grade) | Lower offset voltage reduces DC measurement error, which is important for precision instrumentation and low-level signal amplification. |
| Input Offset Voltage Drift (max) | 0.5 µV/°C (B grade) | 1.0 µV/°C (A grade) | Lower drift maintains accuracy over temperature; critical in applications spanning wide temperature ranges. |
| Gain Error (max) | 0.01% (B grade) | 0.03% (A grade) | Gain error directly affects signal scaling accuracy; tighter gain error improves overall measurement precision. |
| Input Noise (RTI, 1 kHz) | 8 nV/√Hz (B grade) | 8 nV/√Hz (A grade) | Noise floor determines the smallest resolvable signal; both grades share similar noise, so this is not a differentiator. |
| CMRR (min, G=1000) | 126 dB (B grade) | 120 dB (A grade) | Higher common-mode rejection improves rejection of interference and ground noise in differential measurements. |
| Supply Voltage Range | ±2.3 V to ±18 V (4.6 V to 36 V) | ±2.3 V to ±18 V (4.6 V to 36 V) | Identical supply range means both parts are interchangeable for power-supply compatibility. |
| Gain Range (external resistor) | 1 to 1000 | 1 to 1000 | Same gain range ensures functional substitutability for the same signal-conditioning requirements. |
| Package | 8-lead SOIC | 8-lead SOIC | Identical package allows drop-in replacement on the same PCB footprint. |
| Operating Temperature Range | −40 °C to +85 °C | −40 °C to +85 °C | Same temperature range confirms both parts suit the same environmental conditions. |
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 | AD8422BRZ | AD8422ARZ-RL |
|---|---|---|
| Supplier | - | Analog Devices Inc. |
| Part Status | Active | Active |
| Amplifier Type | Instrumentation | Instrumentation |
| Number of Circuits | 1 | 1 |
| Output Type | Rail-to-Rail | Rail-to-Rail |
| Slew Rate | 0.8V/µs | 0.8V/µs |
| -3 dB Bandwidth | 2.2 MHz | 2.2 MHz |
| Current - Input Bias | 200 pA | 500 pA |
| Voltage - Input Offset | 25 µV | 60 µV |
| Supply Current | 300µA | 300µA |
| Current - Output / Channel | 20 mA | 20 mA |
| Voltage - Supply Span(Min) | 4.6 V | 4.6 V |
| Voltage - Supply Span(Max) | 36 V | 36 V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the key differences between the AD8422BRZ and AD8422ARZ-RL?
Both are AD8422 instrumentation amplifiers from Analog Devices in an 8-lead SOIC package. The primary difference is the grade: the AD8422BRZ is the higher-grade B version, while the AD8422ARZ-RL is the A-grade version supplied in tape-and-reel packaging. The B grade offers tighter guaranteed specifications, notably lower offset voltage, lower offset drift, and higher CMRR than the A grade.
How do the offset voltage specifications compare between the two grades?
Per the Analog Devices AD8422 datasheet, the B grade (AD8422BRZ) guarantees a maximum input offset voltage of 70 µV, while the A grade (AD8422ARZ-RL) guarantees a maximum of 150 µV. Both are specified at 25°C with the same test conditions.
Do the AD8422BRZ and AD8422ARZ-RL differ in gain range or bandwidth?
No. Both grades share the same gain equation (G = 1 + 19.8 kΩ/RG) and the same gain range of 1 to 1000. The -3 dB bandwidth versus gain characteristic is common to both grades, so AC performance is essentially identical for a given gain setting.
Are the pinouts and package footprints identical?
Yes. Both parts are offered in the same 8-lead SOIC (R-8) package with identical pin functions, so the PCB land pattern and pinout are interchangeable. The -RL suffix on the AD8422ARZ-RL indicates tape-and-reel packing rather than a different package.
Can the AD8422ARZ-RL be used as a drop-in replacement for the AD8422BRZ?
Electrically and mechanically the parts are pin-compatible, but the A grade has wider guaranteed tolerances (for example, higher maximum offset voltage and offset drift). A substitution is acceptable only if the design's error budget accommodates the A-grade limits; otherwise the B grade should be retained.
What is the difference in offset voltage drift between the two grades?
The AD8422 datasheet specifies a maximum input offset voltage drift of 0.5 µV/°C for the B grade and 1.0 µV/°C for the A grade. This makes the B grade preferable for precision applications over temperature.
Do both parts share the same supply voltage range and quiescent current?
Yes. Both grades operate from a single supply of 4.6 V to 36 V or dual supplies of ±2.3 V to ±18 V, and both draw a typical quiescent current of 300 µA. These parameters are common to the AD8422 family and do not differ by grade.
Why is the AD8422ARZ-RL supplied in tape-and-reel while the AD8422BRZ is not?
The -RL suffix denotes tape-and-reel packaging intended for automated high-volume assembly. The AD8422BRZ is supplied in standard tube or tray packaging. The packaging difference does not affect the electrical specifications of the device.