Part A
AD8226ARZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4203 PCS
- Package
- SOIC-8
- Series
- Linear - Amplificadores - Instrumentação, OP Amps, Buffer Amps
Replacement verdict
Compatible functional replacement candidate
The AD8226ARZ and AD8228ARZ-RL are both single-channel instrumentation amplifiers in the same 8-lead SOIC package, making them a viable functional replacement candidate. However, the AD8228ARZ-RL offers a fixed gain of 10 versus the resistor-programmable gain of the AD8226ARZ, so gain configuration and bandwidth requirements must be validated before substitution.
Package Type
High match
Channel Count
High match
Gain Configuration
Validation required
Bandwidth
Validation required
Parts at a glance
Part B
AD8228ARZ-RL
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 9921 PCS
- Package
- SOIC-8
- Series
- Linear - Amplificadores - Instrumentação, OP Amps, Buffer Amps
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD8226ARZ | AD8228ARZ-RL | Why it matters |
|---|---|---|---|
| Number of Amplifiers | 1 | 1 | Both are single-channel instrumentation amplifiers, so channel count is equivalent for single-signal designs. |
| Gain Setting Method | External resistor (RG) | Pin-selectable fixed gains (G=10 or G=100) | The AD8226 allows any user-defined gain via an external resistor, while the AD8228 offers only two factory-set gains, limiting flexibility in gain-critical designs. |
| Gain Range | 1 to 1000 (set by RG) | 10 or 100 (pin-selectable) | A wider adjustable gain range makes the AD8226 suitable for varied signal amplitudes, whereas the AD8228 is restricted to two discrete gains. |
| Input Offset Voltage (max) | ±200 µV (typical grade dependent) | ±50 µV | Lower offset voltage improves DC accuracy; the AD8228 offers tighter offset, benefiting precision low-level signal measurement. |
| Input Voltage Noise (1 kHz) | ~22 nV/√Hz | ~8 nV/√Hz | Lower noise density improves signal-to-noise ratio for small signals; the AD8228 is preferable in low-noise applications. |
| Bandwidth (−3 dB, G=10) | ~1.5 MHz | ~1.2 MHz | Bandwidth determines the maximum signal frequency the amplifier can handle at a given gain; slight differences affect high-frequency performance. |
| Supply Voltage Range | ±2.3 V to ±18 V (4.6 V to 36 V single supply) | ±2.3 V to ±18 V (4.6 V to 36 V single supply) | Identical supply flexibility means both can operate in the same power rails, easing substitution in existing designs. |
| Supply Current (per amplifier) | ~350 µA | ~400 µA | Lower quiescent current benefits battery-powered and low-power systems; the AD8226 draws slightly less. |
| CMRR (G=10, DC) | ~80 dB (min) | ~100 dB (min) | Higher common-mode rejection improves accuracy in noisy or high common-mode environments; the AD8228 offers superior CMRR. |
| Package | 8-Lead SOIC | 8-Lead SOIC | Identical package and pinout compatibility simplifies PCB substitution between the two parts. |
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 | AD8226ARZ | AD8228ARZ-RL |
|---|---|---|
| Supplier | - | Analog Devices Inc. |
| Part Status | Active | Obsolete |
| Amplifier Type | Instrumentation | Instrumentation |
| Number of Circuits | 1 | 1 |
| Slew Rate | 0.6V/µs | 2.5V/µs |
| -3 dB Bandwidth | 1.5 MHz | 650 kHz |
| Current - Input Bias | 20 nA | 500 pA |
| Voltage - Input Offset | 100 µV | 90 µV |
| Supply Current | 350µA | 850µA |
| Current - Output / Channel | 13 mA | 18 mA |
| Voltage - Supply Span(Min) | 2.2 V | 4.6 V |
| Voltage - Supply Span(Max) | 36 V | 36 V |
| Operating Temperature | -40°C ~ 125°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
| Output Type | Rail-to-Rail | - |
Frequently asked questions
What are the primary functional differences between the AD8226ARZ and AD8228ARZ-RL?
The AD8226ARZ is a wide supply range, rail-to-rail output instrumentation amplifier optimized for high common-mode rejection and low power consumption, while the AD8228ARZ-RL is a precision, low noise instrumentation amplifier featuring a fixed gain of 10 and higher accuracy specifications. The AD8226 offers a gain range of 1 to 1000 set by a single external resistor, whereas the AD8228 provides a fixed gain of 10 with no external gain resistor required.
Are the AD8226ARZ and AD8228ARZ-RL pin-compatible in the SOIC-8 package?
Yes, both devices are offered in an 8-lead SOIC package with the same pinout: pin 1 and pin 8 are gain-setting resistor connections (for the AD8226) or no-connect/internal connections (for the AD8228), pins 2 and 3 are the inverting and non-inverting inputs, pin 4 is the negative supply, pin 5 is the reference, pin 6 is the output, and pin 7 is the positive supply. However, circuit designers must verify that the external gain resistor network used with the AD8226 is removed or reconfigured when substituting the fixed-gain AD8228.
How do the supply voltage ranges of the AD8226ARZ and AD8228ARZ-RL compare?
The AD8226ARZ operates on a dual supply range of ±2.25 V to ±18 V (or 4.5 V to 36 V single supply), while the AD8228ARZ-RL operates on a dual supply range of ±2.25 V to ±18 V (or 4.5 V to 36 V single supply). Both devices support the same supply voltage range, making them interchangeable in terms of power supply requirements.
Which device offers better noise performance for low-level signal amplification?
The AD8228ARZ-RL provides lower input voltage noise (approximately 8 nV/√Hz at 1 kHz) compared to the AD8226ARZ (approximately 22 nV/√Hz at 1 kHz). For applications requiring amplification of low-level signals where noise is critical, the AD8228ARZ-RL is the preferred choice due to its lower noise floor.
What is the gain configuration difference between the AD8226ARZ and AD8228ARZ-RL?
The AD8226ARZ uses a single external resistor to set gain from 1 to 1000 (G = 1 + 49.4 kΩ/RG), providing design flexibility for variable gain applications. The AD8228ARZ-RL has a fixed gain of 10, internally set, which eliminates external gain resistor errors and saves board space but restricts the design to a single gain value.
How do the common-mode rejection ratio (CMRR) specifications compare between the two devices?
The AD8226ARZ specifies a CMRR of 100 dB minimum (G = 1) to 120 dB (G = 1000) at DC, while the AD8228ARZ-RL specifies a CMRR of 100 dB minimum at G = 10. Both devices offer excellent common-mode rejection, but the AD8226ARZ provides higher CMRR at higher gains, making it more suitable for applications with large common-mode voltages and high gain requirements.
Can the AD8228ARZ-RL be used as a drop-in replacement for the AD8226ARZ in an existing design?
No, the AD8228ARZ-RL cannot be used as a direct drop-in replacement for the AD8226ARZ without circuit modification. The AD8226ARZ requires an external gain resistor to set gain, while the AD8228ARZ-RL has a fixed gain of 10 and does not use external gain resistors. Additionally, the AD8228ARZ-RL has lower noise but different bandwidth and settling characteristics. The design must be re-evaluated for gain, noise, bandwidth, and stability before substitution.
What are the bandwidth specifications for the AD8226ARZ and AD8228ARZ-RL?
The AD8226ARZ has a -3 dB bandwidth of 1.5 MHz at G = 1 and 150 kHz at G = 100. The AD8228ARZ-RL has a -3 dB bandwidth of 1.2 MHz at G = 10. The AD8226ARZ offers higher bandwidth at low gains, while the AD8228ARZ-RL provides a fixed bandwidth optimized for its gain of 10 configuration.