Part A
ADR425BRZ
Компания Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4942 ПКС
- Package
- SOIC-8
- Series
- PMIC - Справочник напряжения
Replacement verdict
Compatible functional replacement candidate
The ADR425BRZ and ADR421BR-REEL7 are both precision voltage references from the same ADR42x family, sharing a common SOIC-8 footprint and series-mode topology, but they differ in output voltage and initial accuracy grade. The ADR425BRZ offers a 5.000 V output while the ADR421BR-REEL7 provides 2.500 V, so the two are not electrically interchangeable in a fixed-voltage design without verifying the reference voltage required by the downstream circuit. Designers should confirm output voltage, initial accuracy tolerance, and long-term drift against the target application before substituting one for the other.
Output Voltage
Not compatible
Initial Accuracy Grade
Validation required
Package Type
High match
Operating Temperature Range
High match
Parts at a glance
Part B
ADR421BR-REEL7
Компания Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 5856 ПКС
- Package
- SOIC-8
- Series
- PMIC - Справочник напряжения
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADR425BRZ | ADR421BR-REEL7 | Why it matters |
|---|---|---|---|
| Initial Accuracy | ±0.04% (max) | ±0.04% (max) | Both offer the same tight initial tolerance, so DC accuracy at room temperature is equivalent. |
| Output Voltage | 2.500 V | 2.500 V | Identical nominal output voltage allows direct substitution in a 2.5 V reference socket. |
| Temperature Coefficient | 3 ppm/°C (max) | 3 ppm/°C (max) | Matching low tempco ensures comparable drift performance over the operating temperature range. |
| Initial Accuracy (B grade) | ±0.04% | ±0.04% | Same B-grade accuracy specification confirms equivalent precision class. |
| Supply Current | 0.5 mA (typ) | 0.5 mA (typ) | Equal quiescent current means similar power budget impact in low-power designs. |
| Output Current Capability | 10 mA (source/sink) | 10 mA (source/sink) | Same drive capability supports equivalent load conditions without buffering. |
| Noise (0.1 Hz to 10 Hz) | 3.4 µV p-p (typ) | 1.75 µV p-p (typ) | Lower low-frequency noise in the ADR421 benefits precision ADC and low-level signal applications. |
| Long-Term Drift | 50 ppm/1000 hr (typ) | 50 ppm/1000 hr (typ) | Equivalent long-term stability supports comparable calibration intervals. |
| Package | 8-Lead SOIC | 8-Lead SOIC | Same footprint and package allow drop-in PCB replacement. |
| Operating Temperature Range | -40°C to +125°C | -40°C to +125°C | Identical temperature range ensures suitability for 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 | ADR425BRZ | ADR421BR-REEL7 |
|---|---|---|
| Series | XFET® | XFET® |
| Part Status | Active | Obsolete |
| Reference Type | Series | Series |
| Output Type | Fixed | Fixed |
| Voltage - Output (Min/Fixed) | 5V | 2.5V |
| Current - Output | 10 mA | 10 mA |
| Tolerance | ±0.04% | ±0.04% |
| Temperature Coefficient | 3ppm/°C | 3ppm/°C |
| Noise - 01 Hzto10 Hz | 3.4µVp-p | 1.75µVp-p |
| Voltage - Input | 7V ~ 18V | 4.5V ~ 18V |
| Supply Current | 600µA | 600µA |
| Operating Temperature | -40°C ~ 125°C (TA) | -40°C ~ 125°C (TA) |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the key differences between the ADR425BRZ and ADR421BR-REEL7?
The ADR425BRZ is a 5.000 V precision voltage reference in an 8-lead SOIC package, while the ADR421BR-REEL7 is a 2.500 V precision voltage reference in an 8-lead SOIC package supplied on tape and reel. Both are members of Analog Devices' ADR42x series of low-noise, high-accuracy XFET references, but they differ in output voltage, initial accuracy, and temperature coefficient grades.
What is the output voltage of each device?
The ADR425BRZ provides a fixed 5.000 V output. The ADR421BR-REEL7 provides a fixed 2.500 V output. The output voltage is set internally and cannot be adjusted externally.
What initial accuracy and temperature coefficient grades do these parts offer?
Both are "B" grade devices. The ADR425BRZ offers ±0.04% initial accuracy and 3 ppm/°C maximum temperature coefficient. The ADR421BR-REEL7 offers ±0.04% initial accuracy and 3 ppm/°C maximum temperature coefficient. Both are specified over the −40°C to +125°C temperature range.
Are the ADR425BRZ and ADR421BR-REEL7 pin-compatible?
Yes. Both devices are offered in the same 8-lead SOIC (R-8) package with identical pin functions: pin 1 and pin 8 are not connected, pin 2 is VIN, pin 3 is not connected, pin 4 is GND, pin 5 is TRIM, pin 6 is VOUT, and pin 7 is not connected. This allows a common PCB footprint, but the different output voltages must be accounted for in the design.
What are the supply voltage and quiescent current specifications?
The ADR425BRZ operates from a supply voltage of 7.0 V to 18 V, while the ADR421BR-REEL7 operates from 4.5 V to 18 V. Both devices have a typical quiescent current of 0.5 mA and a maximum of 0.8 mA. The lower minimum supply of the ADR421BR-REEL7 makes it suitable for lower-voltage systems.
How do the noise and long-term stability specifications compare?
Both devices exhibit low output noise of 1.75 µV p-p (0.1 Hz to 10 Hz) typical and 0.1 µV p-p/√Hz at 1 kHz typical. Long-term stability is specified as 50 ppm/1000 hours typical for both the ADR425BRZ and ADR421BR-REEL7. These specifications are identical because both parts share the same XFET reference core.
Can the ADR425BRZ and ADR421BR-REEL7 be used interchangeably in an existing design?
No, not directly. Although they are pin-compatible and share the same package and reference architecture, their output voltages differ (5.000 V vs 2.500 V). A design requiring 5.000 V cannot use the ADR421BR-REEL7 without recalibration or circuit changes, and vice versa. The supply voltage range also differs, so the system rail must be verified against the selected part's minimum VIN.
What is the difference in packaging and ordering format?
The ADR425BRZ is supplied in an 8-lead SOIC tube format (the "Z" suffix denotes RoHS-compliant packaging). The ADR421BR-REEL7 is supplied in an 8-lead SOIC tape-and-reel format (the "REEL7" suffix denotes 7-inch reel packaging), which is intended for automated high-volume assembly. Both are RoHS-compliant.