DESCRIPTION
The LT ®1251/LT1256 are 2-input, 1-output, 40MHz current feedback amplifiers with a linear control circuit that sets the amount each input contributes to the output. These parts make excellent electronically controlled variable gain amplifiers, filters, mixers and faders. The only external components required are the power supply bypass capacitors and the feedback resistors. Both parts operate on supplies from ±2.5V (or single 5V) to ±15V (or single 30V).

FEATURES
■ Accurate Linear Gain Control: ±1% Typ, ±3% Max
■ Constant Gain with Temperature
■ Wide Bandwidth: 40MHz
■ High Slew Rate: 300V/µs
■ Fast Control Path: 10MHz
■ Low Control Feedthrough: 2.5mV
■ High Output Current: 40mA
■ Low Output Noise
   45nV/√Hz at AV = 1
   270nV/√Hz at AV = 100
■ Low Distortion: 0.01%
■ Wide Supply Range: ±2.5V to ±15V
■ Low Supply Current: 13mA
■ Low Differential Gain and Phase: 0.02%, 0.02°

APPLICATIONS
■ Composite Video Gain Control
■ RGB, YUV Video Gain Control
■ Video Faders, Keyers
■ Gamma Correction Amplifiers
■ Audio Gain Control, Faders
■ Multipliers, Modulators
■ Electronically Tunable Filters