FSTD16861: 20-Bit Bus Switch with Level Shifting

The Fairchild Switch FSTD16861 provides 20-bits of high-speed CMOS TTL-compatible bus switching. The low On Resistance of the switch allows inputs to be connected to outputs without adding propagation delay or generating additional ground bounce noise. A diode to VCC has been integrated into the circuit to allow for level shifting between 5V inputs and 3.3V outputs.

The device is organized as a 10-bit or 20-bit bus switch. When OE#1 is LOW, the switch is ON and Port 1A is connected to Port 1B. When OE#2 is LOW, Port 2A is connected to Port 2B. When OE#X is HIGH, a high impedance state exists between the A and B Ports.

Features

• 4ohm switch connection between two ports.
• Minimal propagation delay through the switch.
• Low l_CC.
• Zero bounce in flow-through mode.
• Control inputs compatible with TTL level.
• TruTranslation™ voltage translation from 5.0V inputs to 3.3V outputs
• Power-off high impedance inputs and outputs
• Supports live insertion/withdrawal (Note 1)

Application Notes