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ADA4523-1 is a precision ‘zero-drift’ op-amp from Analog Devices that works across 4.5V to 36V, drawing 6mA worst case.

The output is rail-to-rail, and the input includes the negative rail – working from 100mV below the negative rail to 1.5V below the positive rail.

Maximum offset voltage is ±4µV and, due to self-calibrating circuitry, this drifts at only 0.01µV/°C (max at 5V) – and ADI claims zero drift over time.

Input noise is typically 88nVp-p (0.1Hz to 10Hz) with spectral density 4.2nV/√Hz typical at 1kHz. This is combined with 168dB typical PSRR (power supply rejection, any supply V) and 160dB CMRR (common-mode rejection, -15.1V to +13.5V common, 30V supply).

Open-loop voltage gain is typically 160dB (-14.75Vout to +14.75Vout into 10kΩ, 30V supply). Gain-bandwidth product is typically 5MHz.

Typical application

This is a chopper-stabilised amplifier with circuitry to suppress idle tones at the chopping frequency and its odd harmonics to below the offset voltage. Typical ripple magnitude at the 330kHz chopping frequency, according to ADI, is less than 1µVrms.

A shut-down mode is included for low-power applications, shutting down to <20µA maximum over temperature. When shut-down, the output is high impedance (with caveats).To make shut-down logic-compatible regardless of the amplifier's rails, there is an ‘SDCOM’ pin to connect to logic ground, after which the ‘SD’ pin becomes 3V or 5V logic compatible relative to that pin (logic ‘0’ for shut-down).

Package options are all 8 lead: SOIC, MSOP or LFCSP.

There is an evaluation board (pictured) called EVAL-ADA4523-1ARMZ that includes an MSOP-packaged op-amp connected for 101x non-inverting gain – giving a useable bandwidth of ~39.6kHz. "This limitation in bandwidth acts as a low-pass filter that rejects artefacts generated by the 330kHz internal chopping frequency," according to ADI. "Layout lessens the thermocouple effects of the trace and components that introduce offset voltages greater than the maximum offset voltage."

Applications are foreseen in high dynamic range: test, measurement and instrumentation – data acquisition, reference buffering (see circuit), electronic scales, thermocouple amplifiers, strain gauge amplifiers and low-side current sense, for example.

The product page is here

In 2015, ADI released the ADA4522, a 4.5 to 55V precision low-drift op-amp available in single, dual and quad forms.

As the data sheet of the new ADA4523 mentions ‘per amplifier’ several times, any plans for dual or quad versions ADI?

"We might release a dual or quad amplifier in the future – it's a possibility. As of now, we only have the single version which is ADA4523-1," ADI replied to Electronics Weekly.