AD645

The AD645 is a low noise, precision FET input op amp. It offers the pico amp level input currents of a FET input device coupled with offset drift and input voltage noise comparable to a high performance bipolar input amplifier.

The AD645 has been improved to offer the lowest offset drift in a FET op amp, 1 µV/°C. Offset voltage drift is measured and trimmed at wafer level for the lowest cost possible. An inherently low noise architecture and advanced manufacturing techniques result in a device with a guaranteed low input voltage noise of 2 µV p-p, 0.1 Hz to 10 Hz. This level of dc performance along with low input currents make the AD645 an excellent choice for high impedance applications where stability is of prime concern.

The AD645 is available in six performance grades. The AD645J and AD645K are rated over the commercial temperature range of 0°C to +70°C. The AD645A, AD645B, and the ultra-precision AD645C are rated over the industrial temperature range of -40°C to +85°C. The AD645S is rated over the military temperature range of -55°C to +125°C and is available processed to MIL-STD-883B.

The AD645 is available in an 8-pin plastic mini-DIP, 8-pin header, or in die form.