Part A
AD694ARZ
Công ty Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4975 PCS
- Package
- SOIC-16
- Series
- Interface - Sensor and Detector Interfaces
Replacement verdict
Compatible functional replacement candidate
The AD694ARZ and AD694BR are functionally interchangeable voltage-to-current transmitters sharing the same pinout, package, and core architecture, with the AD694BR offering tightened grade-level specifications. Both are viable substitutes in most 4–20 mA loop applications, though designs operating near the specification limits should validate the grade-dependent tolerances before substitution.
Package Type
High match
Pin Configuration
High match
Output Type
High match
Accuracy Grade
Validation required
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD694ARZ | AD694BR | Why it matters |
|---|---|---|---|
| Grade / Accuracy Class | A grade | B grade | The B grade offers tighter guaranteed specifications than the A grade, affecting precision in critical transmitter loops. |
| Total Unadjusted Error (max) | 0.25% FS | 0.1% FS | Lower total unadjusted error means the B grade delivers higher accuracy without external trimming. |
| Nonlinearity (max) | 0.02% FS | 0.01% FS | Better linearity in the B grade improves fidelity of the 4-20 mA output across the full input range. |
| Input Offset Voltage (max) | 1.0 mV | 0.5 mV | Lower input offset reduces zero-scale error, which is important for accurate low-end current output. |
| Input Offset Drift (max) | 5 µV/°C | 2 µV/°C | Lower drift in the B grade maintains accuracy over temperature in industrial environments. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +85°C | Both parts share the same industrial temperature range, so thermal envelope is not a differentiator. |
| Output Current Range | 4 mA to 20 mA | 4 mA to 20 mA | Identical standard current-loop output ensures functional interchangeability in 4-20 mA systems. |
| Supply Voltage Range | 4.5 V to 36 V | 4.5 V to 36 V | Same wide supply range allows either grade to be used across the same power architectures. |
| Package | 20-Lead SOIC (Wide) | 20-Lead SOIC (Wide) | Identical package and pinout enable drop-in substitution on the same PCB footprint. |
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 | AD694BR |
|---|---|---|
| Supplier | - | Rochester Electronics, LLC |
| Part Status | Active | Obsolete |
| 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 are the main differences between the AD694ARZ and AD694BR?
Both devices are 4–20 mA current transmitters from Analog Devices in the same 16-lead SOIC package and share the same core function. The primary documented difference is the specified accuracy grade: the AD694BR is the higher-grade version with tighter guaranteed nonlinearity and offset error specifications, while the AD694ARZ is the standard grade. The AD694ARZ suffix "Z" denotes RoHS-compliant lead-free packaging per Analog Devices ordering nomenclature.
Are the AD694ARZ and AD694BR pin-compatible and package-compatible?
Yes. Both parts are offered in the same 16-lead SOIC (R-16) package with identical pin functions, so they are drop-in compatible from a footprint and pinout perspective. Substitution is therefore a matter of validating the required accuracy grade against the design's error budget.
What is the function of the AD694?
The AD694 is a monolithic voltage-to-current converter designed to transmit a 4–20 mA signal proportional to an input voltage. It includes an input buffer amplifier, a voltage-to-current converter, and a reference, and is intended for industrial current-loop transmission applications.
What input voltage range does the AD694 support?
The AD694 supports selectable input spans of 0 V to 2 V and 0 V to 10 V, configured via the span selection pin. These spans map to the 4–20 mA output current.
What is the difference in accuracy specification between the A and B grades?
The B grade (AD694BR) is specified with tighter guaranteed error limits than the A grade (AD694ARZ), particularly for nonlinearity and offset. Designers should consult the Analog Devices AD694 datasheet specification table for the exact guaranteed limits applicable to each grade before substituting one for the other.
What supply voltage does the AD694 require?
The AD694 operates from a single supply, with the datasheet specifying operation over a supply range that supports both 4–20 mA loop compliance and internal reference operation. The exact minimum and maximum supply voltages should be verified against the current Analog Devices datasheet for the specific grade.
Can the AD694ARZ be used as a replacement for the AD694BR in an existing design?
Because both are the same die function in the same package, the AD694ARZ can physically replace the AD694BR, but only if the design's accuracy requirements are met by the A-grade specifications. If the circuit was qualified against B-grade guaranteed limits, the substitution must be re-validated against the A-grade datasheet limits.