8x8 Crosspoint Video Switch

The MAX456 is the first monolithic CMOS 8 x 8 video crosspoint switch that significantly reduces component count, board space, and cost. The crosspoint switch contains a digitally controlled matrix of 64 T-switches that connect eight video input signals to any, or all, output channels. Each matrix output connects to eight internal, high-speed (250V/µs), unity-gain-stable buffers capable of driving 400Ω and 20pF to ±1.3V. For applications requiring increased drive capability, the MAX456 outputs can be connected directly to two MAX470 quad, gain-of-two video buffers, which are capable of driving 75Ω loads.

Three-state output capability and internal, programmable active loads make it feasible to parallel multiple MAX456s and form larger switch matrices.

In the 40-pin DIP package, crosstalk (70dB at 5MHz) is minimized, and board area and complexity are simplified by using a straight-through pinout. The analog inputs and outputs are on opposite sides, and each channel is separated by a power-supply line or quiet digital logic line.

Applications

* Video Editing * Video Security Systems * Video Test Equipment

* Routes Any Input Channel to Any Output Channel

* Switches Standard Video Signals

* Serial or Parallel Digital Interface

* Expandable for Larger Switch Matrices

* 80dB All-Channel Off Isolation at 5MHz

* 8 Internal Buffers with: * 250V/µs Slew Rate, Three-State Output Capability,

* Power-Saving Disable Feature, 35MHz Bandwidth