Dual 9 MHz Precision Operational Amplifier

The OP285 is a precision high-speed amplifier featuring the Butler Amplifier front-end. This new front-end design combines the accuracy and low noise performance of bipolar transistors with the speed of JFETs. This yields an amplifier with high slew rates, low offset and good noise performance at low supply currents. Bias currents are also low compared to bipolar designs.

The OP285 offers the slew rate and low power of a JFET amplifier combined with the precision, low noise and low drift of a bipolar amplifier. Input offset voltage is laser-trimmed and guaranteed less than 250 μV. This makes the OP285 useful in dc-coupled or summing applications without the need for special selections or the added noise of additional offset adjustment circuitry. Slew rates of 22 V/μs and a bandwidth of 9 MHz make the OP285 one of the most accurate medium speed amplifiers available.

The combination of low noise, speed and accuracy can be used to build high speed instrumentation systems. Circuits such as instrumentation amplifiers, ramp generators, bi-quad filters and dc-coupled audio systems are all practical with the OP285. For applications that require long term stability, the OP285 has a guaranteed maximum long term drift specification.

The OP285 is specified over the XIND—extended industrial— (−40°C to +85°C) temperature range. The OP285 is available in an 8-lead SOICN surface mount package.

Applications

* High performance audio

* Active filters

* Fast amplifiers

* Integrators

* Low offset voltage: 250 μV

* Low noise: 6 nV/√Hz

* Low distortion: 0.0006%

* High slew rate: 22 V/μs

* Wide bandwidth: 9 MHz

* Low supply current: 5 mA

* Low offset current: 2 nA

* Unity-gain stable

* 8-lead SOICN package