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Applications Information

The EL4094 is a self-contained and calibrated fader

subsystem. When a given channel has 100% gain the circuit

behaves as a current-feedback amplifier in unity-gain

connection. As such, video and transfer distortions are very

low. As the gain of the input is reduced, a 2-quadrant

multiplier is gradually introduced into the signal path and

distortions increase with reducing gain.

The input impedance also changes with gain setting, from

about 1M

Ω at 100% gain down to 16kΩ at zero gain. To

maximize gain accuracy and linearity, the inputs should be

driven from source impedances of 500

Ω or less.

Linearity

The EL4094 is designed to work linearly with ±2V inputs, but

lowest distortion occurs at ±1V levels and below. Errors are

closer to those of a good current-feedback amplifier above

90% gain.

Low-frequency linearity is 0.1% or better for gains 25% to

100% and inputs up to 1V. NTSC differential gain and phase

errors are better than 0.3% and 0.3° for the 25% to 100%

gain range. These distortions are not strongly affected by

Gain Control Gain vs Frequency

Change in V(100%) and V(0%) of

Change in V(100%) and V(0%) of Gain

Control vs Supply Voltage

Change in V(100%) and V(0%) of Gain

Control vs Die Temperature

Supply Current vs Supply Voltage

Maximum Dissipation vs

Ambient Temperature

EL4094