AD8553ARMZ

Overview

The AD8553ARMZ is a precision instrumentation amplifier featuring low noise, rail-to-rail output, and a power-saving shutdown mode. It operates from a single supply of 1.8 V to 5.5 V. Key electrical specifications include a maximum input offset voltage of 20 μV, an input bias current of 2 nA, and a common-mode rejection ratio of 120 dB at G = 100. The device offers a signal bandwidth of 1 kHz for gains between 1 and 1000, with a voltage noise density of 30 nV/√Hz at 1 kHz. Supply current is 1.1 mA in active mode and reduces to less than 4 μA in shutdown.

Feature Summary

• Features a unique architecture allowing paralleling of devices to lower noise without requiring additional external components.
• Incorporates auto-zero technology to continuously correct offset errors induced by changes in input or supply voltage.
• Provides a shutdown capability that significantly reduces total supply current when the device is not needed.
• Delivers rail-to-rail output swing while maintaining high common-mode rejection performance.

Applications

• Strain gauge amplifiers
• Weigh scales
• Pressure sensors
• Thermocouple amplifiers
• Portable medical instruments

Procurement Notes

Verify the specific ordering suffix Z indicates RoHS compliance. Confirm the package type matches the required 10-lead MSOP footprint. Ensure the temperature range specification aligns with industrial requirements. Check datasheet revisions for any updates to electrical characteristics or application circuit recommendations before finalizing procurement.

Selection Notes

Select this component for applications requiring low offset voltage and drift coupled with high common-mode rejection. Consider the shutdown feature for battery-powered systems where power conservation is critical. Evaluate the gain setting resistor requirements to ensure proper operation within the specified bandwidth and noise limits. Verify compatibility with single-supply or dual-supply configurations based on system design constraints.

Part Context

Analog Devices manufactures the AD8553 as part of its precision instrumentation amplifier portfolio. The company specializes in analog, mixed-signal, and digital signal processing technologies. This component targets high-volume applications benefiting from small footprint and low cost. It supports industries including industrial automation, medical devices, and sensor-based measurement systems.

Replacement Considerations

No public confirmed substitute part numbers are available in the provided documentation.

FAQ

How does the AD8553 reduce noise when multiple units are used?

The unique architecture allows paralleling devices to lower noise. By connecting internal voltage-current sources, the circuit noise can be reduced to one over the square root of N times the single IC noise, using only N+1 resistors.

What is the function of the ENABLE pin?

The ENABLE pin controls the shutdown mode. Connecting it to the positive supply enables normal operation, while connecting it to the negative supply turns the device off, reducing supply current to less than 4 μA.

Why is an external buffer amplifier not required for the VREF pin?

Unlike traditional three-op-amp instrumentation amplifiers, parasitic resistance in series with the VREF pin does not degrade CMR performance in the AD8553. This allows the device to maintain high CMR without an external buffer.