The AD8021 is an exceptionally high performance, high gain, low noise, low power, wideband amplifier that can be used in ADC preamps and drivers, instrumentation preamps, active filters, portable instrumentation, line receivers, precision instruments, ultrasound signal processing, and high gain circuits.
The AD8021 is a high‑performance, high‑speed voltage‑feedback amplifier designed for 16‑bit resolution systems. It provides very low voltage and current noise (2.1 nV/V·Hz and 2.1 pA/V·Hz) while drawing only 7 mA quiescent current at a 5 V supply.
The device operates from +2.25 V to +12 V, includes an active‑low disable pin for power saving, and can drive 75 Ω loads. Its small‑signal bandwidth reaches 200 MHz at unity gain and the amplifier settles to 0.01 % in 23 ns. Comprehensive specifications, pin descriptions, and application notes are provided in the datasheet.
| Small Signal Bandwidth (G=-1) | 200 MHz |
|---|---|
| Input Voltage Noise (50 kHz) | 2.1 nV/V·Hz |
| Input Current Noise (50 kHz) | 2.1 pA/V·Hz |
Pin 8 (DISABLE) is active‑low; pulling it low disables the amplifier, while a high level enables it.
The amplifier provides a 200 MHz small‑signal bandwidth at G = ‑1.