精密放大器 FET INPT, SINGLE SPLY AMP
Product Details
The AD820 is a precision, low power FET input op amp that can operate from a single supply of 5 V to 36 V, or dual supplies of ±2.5 V to ±18 V. It has true single-supply capability, with an input voltage range extending below the negative rail, allowing the AD820 to accommodate input signals below ground in the single-supply mode. Output voltage swing extends to within 10 mV of each rail, providing the maximum output dynamic range.
Offset voltage of 800 μV maximum, offset voltage drift of 2 μV/°C, typical input bias currents below 25 pA, and low input voltage noise provide dc precision with source impedances up to 1 GΩ. 1.8 MHz unity gain bandwidth, −93 dB THD at 10 kHz, and 3 V/μs slew rate are provided for a low supply current of 800 μA. The AD820 drives up to 350 pF of direct capacitive load and provides a minimum output current of 15 mA. This allows the amplifier to handle a wide range of load conditions. This combination of ac and dc performance, plus the outstanding load drive capability, results in an exceptionally versatile amplifier for the single-supply user.
The AD820 is available in two performance grades. The A and B grades are rated over the industrial temperature range of −40°C to +85°C. The AD820 is offered in three 8-lead package options: plastic DIP PDIP, surface mount SOIC and MSOP.
**Applications**
* Battery-powered precision instrumentation
* Photodiode preamps
* Active filters
* 12-bit to 14-bit data acquisition systems
* Medical instrumentation
* Low power references and regulators
Data Sheet, Rev. F, 11/08
### Features and Benefits
Output swings rail-to-rail
Input voltage range extends below ground
Single-supply capability from 5 V to 36 V
Dual-supply capability from ±2.5 V to ±18 V
Capacitive load drive up to 350 pF
Minimum output current of 15 mA
800 μA maximum quiescent current
Unity-gain bandwidth: 1.8 MHz
Slew rate of 3 V/μs
800 μV maximum input offset voltage
2 μV/°C typical offset voltage drift
25 pA maximum input bias current