Part A
ADR4520BRZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4412 Stückzahl
- Package
- SOIC-8
- Series
- PMIC Spannung Referenz
Replacement verdict
Compatible functional replacement candidate
The ADR4540ARZ and ADR4520BRZ are both high-precision voltage references from the same ADR45xx family, sharing a common SOIC-8 footprint and identical pinout, which makes them mechanically interchangeable on an existing PCB. However, they differ in output voltage (4.096 V vs 2.048 V) and initial accuracy grade, so the ADR4520BRZ cannot directly substitute for the ADR4540ARZ in circuits that depend on the 4.096 V reference level. The ADR4520BRZ offers a tighter B-grade initial accuracy, making it a viable candidate only where the lower 2.048 V output and the associated recalibration of downstream circuitry are acceptable.
Output Voltage
Not compatible
Package Type
High match
Pin Configuration
High match
Initial Accuracy Grade
Validation required
Parts at a glance
Part B
ADR4540ARZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 3340 Stückzahl
- Package
- SOIC-8
- Series
- PMIC Spannung Referenz
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADR4540ARZ | ADR4520BRZ | Why it matters |
|---|---|---|---|
| Output Voltage | 4.096 V | 2.048 V | The reference voltage sets the full-scale input range of an ADC or DAC; a different value directly changes the system's measurement or output scaling. |
| Initial Accuracy | ±0.02% (A grade) | ±0.02% (B grade) | Initial accuracy determines the untrimmed error at room temperature; both grades offer the same tight tolerance here, so accuracy alone does not differentiate them. |
| Temperature Coefficient | 2 ppm/°C (A grade) | 2 ppm/°C (B grade) | Drift over temperature dominates total error in precision systems; matching tempco values mean thermal performance is comparable between the two. |
| Output Current Capability | 10 mA (source/sink) | 10 mA (source/sink) | Drive capability determines whether the reference can supply the load directly or needs buffering; identical ratings mean the same load handling applies. |
| Supply Voltage Range | 3.0 V to 15 V | 3.0 V to 15 V | The supply range must accommodate the system rail; identical ranges mean both parts are interchangeable from a power-supply standpoint. |
| Operating Temperature Range | −40 °C to +125 °C | −40 °C to +125 °C | The temperature range defines the environments where the part is guaranteed; identical ranges mean equal suitability for industrial and extended-temperature applications. |
| Package | 8-Lead SOIC (R) | 8-Lead SOIC (R) | Package compatibility affects PCB footprint and assembly; identical SOIC packages allow drop-in replacement without layout changes. |
| Long-Term Drift | 25 ppm/1000 h | 25 ppm/1000 h | Long-term drift affects calibration stability over the product lifetime; matching values mean comparable recalibration intervals. |
| Output Noise (0.1 Hz to 10 Hz) | 1.25 µV p-p | 0.62 µV p-p | Low-frequency noise limits resolution in high-precision DC measurements; the lower noise of the ADR4520BRZ benefits low-level signal acquisition. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADR4520BRZ | ADR4540ARZ |
|---|---|---|
| Part Status | Active | Active |
| Reference Type | Series | Series |
| Output Type | Fixed | Fixed |
| Voltage - Output (Min/Fixed) | 2.048V | 4.096V |
| Current - Output | 10 mA | 10 mA |
| Tolerance | ±0.02% | ±0.04% |
| Temperature Coefficient | 2ppm/°C | 4ppm/°C |
| Noise - 01 Hzto10 Hz | 1µVp-p | 2.7µVp-p |
| Voltage - Input | 3V ~ 15V | 4.2V ~ 15V |
| Supply Current | 950µA | 950µA |
| 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 ADR4540ARZ and ADR4520BRZ voltage references?
The ADR4540ARZ provides a 4.096 V output with an initial accuracy of ±0.02% (A grade), while the ADR4520BRZ provides a 2.048 V output with an initial accuracy of ±0.04% (B grade). Both are low-noise, high-accuracy voltage references in the same SOIC-8 package, but they differ in output voltage and accuracy grade.
Are the ADR4540ARZ and ADR4520BRZ pin-compatible?
Yes. Both devices are offered in the same 8-lead SOIC package with identical pin functions (VIN, VOUT, GND, TRIM, and noise-reduction/filter pins), so they share the same PCB land pattern. However, the different output voltages mean the circuit must be validated for the new reference value before substitution.
What is the initial accuracy and temperature coefficient of each part?
The ADR4540ARZ (A grade) has an initial accuracy of ±0.02% and a temperature coefficient of 2 ppm/°C max. The ADR4520BRZ (B grade) has an initial accuracy of ±0.04% and a temperature coefficient of 2 ppm/°C max. Both grades are specified over the −40°C to +125°C temperature range.
How do the output voltage noise specifications compare?
Both devices are low-noise references. The ADR4540ARZ specifies 0.1 Hz to 10 Hz noise of 2.7 µV p-p (typical) and wideband noise of 90 nV/√Hz at 1 kHz. The ADR4520BRZ specifies 0.1 Hz to 10 Hz noise of 1.25 µV p-p (typical) and wideband noise of 45 nV/√Hz at 1 kHz, reflecting its lower output voltage.
What are the operating supply voltage and current requirements?
Both the ADR4540ARZ and ADR4520BRZ operate from a supply voltage of 2.7 V to 5.5 V and typically draw 950 µA of quiescent current. The minimum supply headroom must accommodate the respective output voltage (4.096 V or 2.048 V) plus dropout.
Can the ADR4520BRZ replace the ADR4540ARZ in an existing design?
Not directly. Although the packages and pinouts are identical, the output voltage differs (2.048 V versus 4.096 V), which changes the reference value seen by the ADC or DAC. The design must be re-evaluated for full-scale range, gain settings, and compliance with the new reference voltage before substitution.
What are the operating temperature ranges and package options?
Both the ADR4540ARZ and ADR4520BRZ are specified over the −40°C to +125°C industrial temperature range and are available in an 8-lead SOIC package (RZ suffix). Both are also offered in other grades and package options per the manufacturer's datasheet.