features
High Linearity Near Limiting
Fast Recovery from Overdrive: 2.4 ns
IiMiting Voltage Accuracy: ±15 mV
−3dB Bandwidth (G = +1): 450 MHz
Slew Rate: 1000 V/μs
±5-V and 5-V Supply Operation
Unity Gain Version of the OPA689
IF Limiting Amplifiers
AM Signal Generation
Non−Linear Analog Signal Processing
High Speed Comparators

applications
Fast Limiting ADC Input Buffers
CCD Pixel Clock Stripping
Video Sync Stripping
HF Mixers

description
The OPA688 is a wideband, unity gain stable voltage-feedback op amp that offers bipolar output voltage limiting.
Two buffered limiting voltages take control of the output when it attempts to drive beyond these limits. This new
output limiting architecture holds the limiter offset error to ±15 mV. The op amp operates linearly to within
30 mV of the output limit voltages.
The combination of narrow nonlinear range and low limiting offset allows the limiting voltages to be set within
100 mV of the desired linear output range. A fast 2.4-ns recovery from limiting ensures that overdrive signals
will be transparent to the signal channel. Implementing the limiting function at the output, as opposed to the
input, gives the specified limiting accuracy for any gain, and allows the OPA688 to be used in all standard op
amp applications.
Non-linear analog signal processing will benefit from the OPA688s sharp transition from linear operation to
output limiting. The quick recovery time supports high-speed applications.
The OPA688M is available in an industry standard pinout CDIP-8 package. For higher gain, or transimpedance
applications requiring output limiting with fast recovery, consider the OPA689M.