Part A
AD8221ARZ
Компания Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4567 ПКС
- Package
- SOIC-8
- Series
- Линейные - Усилетели - Приборы, ОП Усилетели, Буферные Усилетели
Replacement verdict
Compatible functional replacement candidate
The AD8221BRZ-RL is a higher-grade variant of the AD8221ARZ, sharing identical pinout, package, and core instrumentation amplifier architecture, making it a viable functional replacement candidate. The B-grade offers tighter gain error, lower offset voltage, and improved CMRR specifications, so it can substitute the A-grade in most precision signal-conditioning designs, though the tighter performance tolerances should be validated against the application's error budget.
Package and Pinout
High match
Amplifier Architecture
High match
Gain Error and Offset Voltage
Validation required
CMRR and Temperature Grade
Validation required
Parts at a glance
Part B
AD8221BRZ-RL
Компания Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 7281 ПКС
- Package
- SOIC-8
- Series
- Линейные - Усилетели - Приборы, ОП Усилетели, Буферные Усилетели
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD8221ARZ | AD8221BRZ-RL | Why it matters |
|---|---|---|---|
| Gain Error (G=1, max) | 0.1% | 0.02% | Lower gain error improves absolute accuracy of the amplified signal, which is critical in precision measurement and bridge transducer applications. |
| Input Offset Voltage (max) | 60 µV | 25 µV | Offset voltage directly adds DC error to the measured signal; a lower guaranteed offset enables more accurate low-level signal acquisition. |
| Input Offset Voltage Drift (max) | 0.8 µV/°C | 0.3 µV/°C | Drift determines offset stability over temperature; lower drift is important for systems operating across wide temperature ranges without recalibration. |
| Input Bias Current (max) | 1.5 nA | 1.0 nA | Bias current flowing through source impedance creates error voltage; lower bias current benefits high-impedance sensor interfaces. |
| CMRR (G=1, min) | 80 dB | 90 dB | Common-mode rejection determines how well the amplifier suppresses unwanted common-mode noise, essential in noisy industrial environments. |
| Noise (RTI, 1 kHz, typ) | 8 nV/√Hz | 8 nV/√Hz | Input-referred noise sets the minimum resolvable signal; both grades share the same typical noise, so noise performance is not a differentiator. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +125°C | The wider temperature range of the B grade allows use in harsher environments and provides margin in thermally stressed designs. |
| Supply Voltage Range | ±2.3 V to ±18 V | ±2.3 V to ±18 V | Identical supply range means both parts are interchangeable for power supply design and can operate from the same rails. |
| Package / Pinout | 8-Lead SOIC | 8-Lead SOIC | Same package and pinout allow direct drop-in replacement on an existing PCB without layout changes. |
| Gain Bandwidth Product | 825 kHz (G=1) | 825 kHz (G=1) | Identical bandwidth means AC response and settling behavior are the same, so dynamic performance is unaffected by grade selection. |
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 | AD8221ARZ | AD8221BRZ-RL |
|---|---|---|
| Part Status | Active | Active |
| Amplifier Type | Instrumentation | Instrumentation |
| Number of Circuits | 1 | 1 |
| Slew Rate | 2V/µs | 2V/µs |
| -3 dB Bandwidth | 825 kHz | 825 kHz |
| Current - Input Bias | 500 pA | 200 pA |
| Voltage - Input Offset | 60 µV | 25 µV |
| Supply Current | 900µA | 900µA |
| Current - Output / Channel | 18 mA | 18 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 main differences between the AD8221ARZ and AD8221BRZ-RL?
Both are AD8221 instrumentation amplifiers in an 8-lead SOIC package. The primary difference is the grade: the AD8221ARZ is the A-grade with a specified gain error of 0.1% maximum (G=1) and offset voltage of 60 µV maximum, while the AD8221BRZ-RL is the higher-precision B-grade with gain error of 0.02% maximum (G=1) and offset voltage of 25 µV maximum. The BRZ-RL is supplied in tape-and-reel packaging, whereas the ARZ is typically supplied in tube packaging.
Are the AD8221ARZ and AD8221BRZ-RL pin-compatible?
Yes. Both devices are offered in the same 8-lead SOIC (R-8) package with identical pin functions, so they are pin-compatible and share the same PCB land pattern.
Can the AD8221ARZ be used as a drop-in replacement for the AD8221BRZ-RL?
They are pin-compatible, but the B-grade offers tighter offset voltage, offset drift, and gain error specifications than the A-grade. A substitution is acceptable only if the A-grade specifications meet the design's error budget; otherwise the higher precision of the B-grade is required.
What is the gain range and gain-setting method for these amplifiers?
Both the AD8221ARZ and AD8221BRZ-RL are programmable-gain instrumentation amplifiers in which gain is set by a single external resistor between the RG pins. Gain is programmed from 1 to 1000 using the manufacturer's gain equation, and both grades support the same gain range.
Do the AD8221ARZ and AD8221BRZ-RL share the same supply voltage and bandwidth specifications?
Yes. Both grades operate from dual supplies of ±2.3 V to ±18 V and provide the same typical bandwidth (approximately 825 kHz at G=1) and the same 1.5 V/µs typical slew rate, since they are the same core amplifier offered in different precision grades.
What is the difference in packaging between the AD8221ARZ and AD8221BRZ-RL?
The AD8221ARZ is supplied in standard tube packaging, while the AD8221BRZ-RL suffix indicates tape-and-reel packaging intended for automated assembly. Both use the identical 8-lead SOIC body.
Which grade should be selected for a precision bridge measurement application?
For precision bridge or transducer measurements where offset and gain errors dominate the error budget, the AD8221BRZ-RL is the appropriate choice because its 25 µV maximum offset voltage and 0.02% maximum gain error (G=1) provide tighter accuracy than the A-grade. The AD8221ARZ is suitable where the wider A-grade tolerances are acceptable.