Fast Settling, JFET Input Operational Amplifier

The LT1122 JFET input operational amplifier combines high speed and precision performance.

A unique poly-gate JFET process minimizes gate series resistance and gate-to-drain capacitance, facilitating wide bandwidth performance, without degrading JFET transistor matching.

It slews at 80V/μs and settles in 340ns. The LT1122 is internally compensated to be unity-gain stable, yet it has a bandwidth of 14MHz at a supply current of only 7mA. Its speed makes the LT1122 an ideal choice for fast settling 12-bit data conversion and acquisition systems.

The LT1122 offset voltage of 120μV, and voltage gain of 500,000 also support the 12-bit accurate applications.

The input bias current of 10pA and offset current of 4pA combined with its speed allow the LT1122 to be used in such applications as high speed sample and hold amplifiers, peak detectors, and integrators.

Applications

* Fast 12-Bit D/A Output Amplifiers

* High Speed Buffers

* Fast Sample-and-Hold Amplifiers

* High Speed Integrators

* Voltage to Frequency Converters

* Active Filters

* Log Amplifiers

* Peak Detectors

* 100% Tested Settling Time to 1mV at Sum Node, 10V Step

* 340ns Typ* 540ns Max

* Tested with Fixed Feedback Capacitor

* Slew Rate 60V/μs Min

* Gain-Bandwidth Product 14MHz

* Power Bandwidth (20VP-P) 1.2 MHz

* Unity-Gain Stable; Phase Margin 60°

* Input Offset Voltage 600μV Max

* Input Bias Current

* 25°C 75pA Max

* 70°C 600pA Max

* Input Offset Current

* 25°C 40pA Max

* 70°C 150pA Max

* Low Distortion