Part A
AD694ARZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4975 Stückzahl
- Package
- SOIC-16
- Series
- Sensor- und Detektorschnittstellen
Replacement verdict
Compatible functional replacement candidate
The AD694ARZ is a functionally compatible replacement candidate for the AD694BRZ, sharing the same voltage-to-current transmitter architecture, pinout, and package. The primary distinction is the specified grade performance, where the BRZ offers tighter guaranteed accuracy over temperature. Designers should validate that the ARZ grade's accuracy specifications meet the requirements of the target application before substituting.
Function and Output Type
High match
Package and Pinout
High match
Accuracy Grade
Validation required
Supply Voltage Range
High match
Parts at a glance
Part B
AD694BRZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 3768 Stückzahl
- Package
- SOIC-16
- Series
- Sensor- und Detektorschnittstellen
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD694BRZ | AD694ARZ | Why it matters |
|---|---|---|---|
| Grade / Accuracy Class | B grade (higher accuracy) | A grade (standard accuracy) | The B grade offers tighter guaranteed specifications, which directly affects total error budget in precision current-loop transmitters. |
| Total Unadjusted Error (max) | ±0.05% FS | ±0.10% FS | Determines the worst-case output error without calibration; the B grade halves the guaranteed error versus the A grade. |
| Nonlinearity (max) | ±0.005% FS | ±0.01% FS | Linearity impacts fidelity of the 4-20 mA output across the full input span; tighter nonlinearity improves measurement accuracy. |
| Input Offset Voltage (max) | ±0.5 mV | ±1.0 mV | Lower input offset reduces zero-scale error in the voltage-to-current conversion, important for accurate 4 mA low-end calibration. |
| Input Offset Drift (max) | ±5 µV/°C | ±10 µV/°C | Drift over temperature affects stability of the loop current in industrial environments; the B grade is twice as stable. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +85°C | Both parts share the industrial temperature range, so environmental suitability is equivalent. |
| Output Current Range | 4 mA to 20 mA | 4 mA to 20 mA | The standard 4-20 mA loop output is the core function; identical range means functional interchangeability in the loop. |
| Supply Voltage Range | +4.5 V to +36 V | +4.5 V to +36 V | Wide common supply range allows use in both 5 V and 24 V industrial systems without redesign. |
| Package | 8-Lead SOIC | 8-Lead SOIC | Identical package and pinout enable drop-in board replacement between the two grades. |
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 | AD694ARZ | AD694BRZ |
|---|---|---|
| Part Status | Active | Active |
| Type | Current Transmitter | Current Transmitter |
| Input Type | Voltage | Voltage |
| Output Type | Voltage | Voltage |
| Supply Current | 23 mA | 23 mA |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What is the primary difference between the AD694BRZ and AD694ARZ?
The main difference is the specified grade and accuracy. The AD694BRZ is the higher-grade version, offering tighter guaranteed specifications such as lower initial offset voltage and reduced offset drift compared to the AD694ARZ, which is the standard-grade version. Both are functionally identical 4–20 mA current transmitters in a 16-lead SOIC package.
Are the AD694BRZ and AD694ARZ pin-compatible and package-compatible?
Yes. Both devices are offered in the same 16-lead SOIC (R-16) package with identical pin functions, so they are pin-for-pin compatible and share the same PCB land pattern.
Can the AD694ARZ be used as a drop-in replacement for the AD694BRZ?
Physically yes, but not necessarily electrically in a precision application. The AD694ARZ has wider guaranteed error limits than the AD694BRZ, so substituting it may degrade total system accuracy. The substitution should only be made after verifying that the ARZ grade's offset, drift, and gain error specifications meet the design requirements.
What are the key guaranteed specifications that differ between the two grades?
The B-grade (AD694BRZ) guarantees tighter maximum input offset voltage and lower offset voltage drift over temperature than the A-grade (AD694ARZ). Designers should consult the official Analog Devices AD694 datasheet for the exact guaranteed limits for each grade before selecting a part.
Do both parts operate over the same temperature range?
Yes. Both the AD694BRZ and AD694ARZ are specified for the industrial temperature range of −40°C to +85°C, so the operating temperature range is not a differentiator between the two grades.
Are the AD694BRZ and AD694ARZ functionally identical in operation?
Yes. Both are monolithic 4–20 mA current-loop transmitters with the same functional blocks, including the input amplifier, voltage-to-current converter, and adjustable reference, and both support the same output current range and supply voltage range. They differ only in guaranteed accuracy grade.
Which grade should be selected for a precision 4–20 mA transmitter design?
For designs where total error budget is critical, the AD694BRZ is the appropriate choice because its tighter guaranteed offset and drift specifications reduce measurement error. The AD694ARZ is suitable for applications where the wider A-grade error limits are acceptable.