Bus Switch 1-Element CMOS 8-IN 20-Pin TVSOP T/R

The SN74CBT6845C is a high-speed TTL-compatible FET bus switch with low ON-state resistance (ron), allowing for minimal propagation delay. Active Undershoot-Protection Circuitry on the A and B ports of the SN74CBT6845C provides protection for undershoot up to -2 V by sensing an undershoot event and ensuring that the switch remains in the proper OFF state. The device also precharges the B port to a user-selectable bias voltage (BIASV) to minimize live-insertion noise.The SN74CBT6845C is an 8-bit bus switch with a single output-enable (OE) input. When OE is low, the 8-bit bus switch is ON, and the A port is connected to the B port, allowing bidirectional data flow between ports. When OE is high, the 8-bit bus switch is OFF, and a high-impedance state exists between the A and B ports. The B port is precharged to BIASV through the equivalent of a 10-k? resistor when OE is high, or if the device is powered down (VCC = 0 V).

• Undershoot Protection for Off-Isolation on A and B Ports Up To -2 V
• B-Port Outputs Are Precharged by Bias Voltage (BIASV) to Minimize Signal Distortion During Live Insertion and Hot-Plugging
• Supports PCI Hot Plug
• Bidirectional Data Flow, With Near-Zero Propagation Delay
• Low ON-State Resistance (ron) Characteristics (ron = 3 ? Typical)
• Low Input/Output Capacitance Minimizes Loading and Signal Distortion (Cio(OFF) = 5.5 pF Typical)
• Data and Control Inputs Provide Undershoot Clamp Diodes
• Low Power Consumption (ICC = 3 µA Max)