4-Input Video Multiplexer with 75MHz Current Feedback Amplifier

The LT1204 is a 4-input video multiplexer designed to drive 75Ω cables and easily expand into larger routing systems. Wide bandwidth, high slew rate, and low differential gain and phase make the LT1204 ideal for broadcast quality signal routing. Channel separation and disable isolation are greater than 90dB up to 10MHz. The channel-to-channel output switching transient is only 40mVP-P, with a 50ns duration, making the transition imperceptible on high quality monitors.

A unique feature of the LT1204 is its ability to expand into larger routing matrices. This is accomplished by a patent pending circuit that bootstraps the feedback resistors in the disable condition, raising the true output impedance of the circuit. The effect of this feature is to eliminate cable misterminations in large systems.

The large input and output signal levels supported by the LT1204 when operated on ±15V supplies make it ideal for general purpose analog signal selection and multiplexing. A shutdown feature reduces the supply current to 1.5mA.

Applications

* Broadcast Quality Video Multiplexing

* Large Matrix Routing

* Medical Imaging

* Large Amplitude Signal Multiplexing

* Programmable Gain Amplifiers

* 0.1dB Gain Flatness > 30MHz

* Channel Separation at 10MHz: 90dB

* Input 40mV Switching Transient, Input Referred

* −3dB Bandwidth, AV = 2, RL = 150Ω: 75MHz

* Channel-to-Channel Switching Time: 120ns

* Easy to Expand for More Inputs

* Large Input Range: ±6V

* 0.04% Differential Gain, RL = 150Ω

* 0.06° Differential Phase, RL = 150Ω

* High Slew Rate: 1000V/µs

* Output Swing, RL = 400Ω: ±13V

* Wide Supply Range: ±5V to ±15V