ADA4806-1 Low-Power, Multimode, Rail-to-Rail Amplifier for Driving SAR ADCs

ADI's ADA4806-1 is a high-speed, voltage feedback, rail-to-rail output, single operational amplifier with three power modes: full power mode, sleep mode, and shutdown mode. In full power mode, this amplifier provides a wide bandwidth of 105 MHz at a gain of +1, a fast slew rate 160 V/μs, and excellent DC precision with a low input offset voltage of 125 μV (maximum) and an input offset voltage drift of 1.5 μV/°C (maximum), while consuming only 500 μA of quiescent current. Despite being a low-power amplifier, the ADA4806-1 provides excellent overall performance, making it ideal for low-power, high-resolution data conversion systems.

For data conversion applications where minimizing power dissipation is paramount, the ADA4806-1 offers a method to reduce power by dynamically scaling the quiescent power of the ADC driver with the sampling rate of the system by switching the amplifier to a lower power mode between samples.

Sleep mode reduces the amplifier quiescent current to 74 μA and provides a fast turn-on time of only 0.45 μs, enabling the use of dynamic power scaling for sample rates approaching 2 MSPS. For additional power savings at lower sample rates, the shutdown mode further reduces the quiescent current to only 2.9 μA.

The ADA4806-1 operates over a wide range of supply voltages and is fully specified at supplies of 3 V, 5 V, and ±5 V. This amplifier is available in a compact, 8-lead SOT-23 package and is rated to operate over the industrial temperature range of -40°C to +125°C.