Low Power, Unity Gain Fully Differential Amplifier & ADC Driver

The AD8476 is a very low power, fully differential precision amplifier with integrated gain resistors for unity gain. It is an ideal choice for driving low power, high performance ADCs as a single-ended-to-differential or differential-to-differential amplifier. It provides a precision gain of 1, common-mode level shifting, low temperature drift, and rail-to-rail outputs for maximum dynamic range.

The AD8476 also provides overvoltage protection from large industrial input voltages up to ±23 V while operating on a dual 5 V supply. Power dissipation on a single 5 V supply is only 1.5 mW.

The AD8476 works well with SAR, Σ-Δ, and pipeline converters. The high current output stage of the part allows it to drive the switched capacitor front-end circuits of many ADCs with minimal error.

Unlike many differential drivers on the market, the AD8476 is a high precision amplifier. With 200 μV maximum output offset, 39 nV/√Hz noise, and −102 dB THD + N at 10 kHz, the AD8476 pairs well with low power, high accuracy converters.

Considering its low power consumption and high precision, the slew-enhanced AD8476 has excellent speed, settling to 16-bit precision for 250 kSPS acquisition times.

The AD8476 is available in a space-saving 8-lead MSOP package. It is fully specified over the −40°C to +125°C temperature range.

Applications

* ADC driver

* Differential instrumentation amplifier building block

* Single-ended-to-differential converter

* Battery powered instruments

* Very low power

- 330 μA supply current

* Fully differential or single-ended inputs/outputs

* Differential output designed to drive precision ADCs

- Drives switched capacitor and Σ-Δ ADCs

- Rail-to-rail output

* VOCM pin adjusts output common mode

* Robust overvoltage up to 18 V beyond supplies

* High performance

- Suitable for driving 16-bit converter up to 250 kSPS

- 39 nV/√Hz output noise

- 1 ppm/°C gain drift

- 200 μV maximum output offset

- 10 V/μs slew rate

- 5 MHz bandwidth

* Single supply: 3 V to 18 V

* Dual supplies: ±1.5 V to ±9 V