Analog Devices Inc. AD8228BRMZ-RL

Overview

AD8228BRMZ-RL from Analog Devices is a precision instrumentation amplifier with pin-strappable gains of 10 or 100, 2 ppm/°C gain drift (B grade), 50 μV max input offset voltage, and 100 dB CMRR at DC–60 Hz. It operates from ±2.3 V to ±18 V supplies and delivers 650 kHz bandwidth at G = 10, serving bridge-based sensor signal conditioning in industrial weigh scales and strain gage interfaces.

For engineers reviewing the AD8228BRMZ-RL datasheet, AD8228BRMZ-RL pinout, AD8228BRMZ-RL application, or AD8228BRMZ-RL equivalent, this page provides verified technical context, real-world design meaning for key specs, validated pin functions, application-specific implementation guidance, and two confirmed alternative parts with documented functional and application differences.

Technical Context

The AD8228BRMZ-RL uses a three-op-amp architecture with laser-trimmed internal resistors to achieve 0.02% gain error and 2 ppm/°C gain drift (B grade, G = 10). Its input stage employs matched bipolar transistors and on-chip bias compensation, enabling 0.6 nA max input bias current and 0.8 μV/°C max input offset drift.

Gain selection is implemented via Pins 2 (G1) and 3 (G2): open for G = 10, shorted for G = 100. The reference terminal (Pin 6) sets output common-mode level with 20 kΩ input impedance and ±VS voltage range, supporting single-supply ADC interfacing when driven by a low-impedance source (<1 Ω).

Key Specifications

Pinout & Package

AD8228BRMZ-RL is housed in an 8-lead MSOP package (3 mm × 3 mm, 0.65 mm pitch), optimized for compact, high-density PCB layouts while maintaining thermal resistance of 135°C/W (4-layer JEDEC board).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar instrumentation amplifier applications.

Compared with AD8221ARMZ and INA128UA, AD8228BRMZ-RL delivers the lowest gain drift (2 ppm/°C), highest CMRR at high frequency (105 dB @ 2 kHz), and guaranteed fixed gains-making it optimal for metrology-grade bridge signal conditioning where long-term stability outweighs gain flexibility.

Availability

AD8228BRMZ-RL is available at Aetrix Electronics and suitable for industrial weigh scales, process control transducer interfaces, and medical instrumentation requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for AD8228BRMZ-RL includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The AD8228BRMZ-RL belongs to Analog Devices' precision instrumentation amplifier product line, engineered specifically for high-accuracy DC-coupled sensor signal conditioning in industrial, medical, and test equipment where gain stability, low offset, and noise immunity are critical.

FAQ

What gain options does the AD8228BRMZ-RL support, and how are they configured?

The AD8228BRMZ-RL supports two fixed gains: 10 and 100. Gain is selected solely by the state of Pins 2 (G1) and 3 (G2): leave both pins unconnected for G = 10; short them together for G = 100. No external resistors are needed, and the internal laser-trimmed network ensures 0.02% gain error and 2 ppm/°C drift (B grade) at G = 10. This configuration is defined in the AD8228BRMZ-RL datasheet Figure 42 and Table 6.

What is the maximum common-mode input voltage for AD8228BRMZ-RL at ±15 V supplies?

At ±15 V supplies, the AD8228BRMZ-rl supports a common-mode input voltage range of −13.1 V to +13.8 V (i.e., −VS + 2.0 V to +VS − 1.2 V) over −40°C to +85°C. This is specified in Table 2 and Table 3 under "Input Operating Voltage Range" and confirmed in Figure 11 and Figure 13 of the AD8228BRMZ-RL datasheet. Exceeding these limits reduces output swing and may degrade CMRR.

Can AD8228BRMZ-RL drive a 12-bit SAR ADC directly, and what REF pin considerations apply?

Yes, AD8228BRMZ-RL can directly drive a 12-bit SAR ADC when its REF pin is tied to a stable, low-impedance midsupply voltage (e.g., 2.5 V for a 5 V ADC). The REF pin defines output common-mode level with 20 kΩ input impedance; source impedance must be <1 Ω to avoid CMRR degradation. This requirement is detailed in the "Reference Terminal" section (page 17) of the AD8228BRMZ-RL datasheet.

How does AD8228BRMZ-RL handle input overvoltage conditions beyond the supply rails?

The AD8228BRMZ-RL input structure tolerates ~3.5 V beyond the supply rails under DC overload. For larger overvoltages (e.g., defibrillator pulses), external 600 Ω series resistors per input are recommended to limit current to ≤6 mA, calculated as R_LIMIT ≥ (V_IN − V_SUPPLY) / 6 mA. This protection method is specified in the "Input Protection" section (page 18) of the AD8228BRMZ-RL datasheet.

What decoupling capacitors are required for stable operation of AD8228BRMZ-RL?

AD8228BRMZ-RL requires a 0.1 μF ceramic capacitor placed within 1 mm of each supply pin (+VS and −VS), plus a bulk 10 μF tantalum capacitor shared with other ICs on the same rail. This dual-stage decoupling is mandated in the "Layout" section (page 17) and illustrated in Figure 45 of the AD8228BRMZ-RL datasheet to maintain PSRR > 124 dB and suppress supply-induced offset errors.