FSTD3125: 4-Bit Bus Switch with Level Shifting

Fairchild switch FSTD3125 provides four high-speed CMOS TTL-compatible bus switches. 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 four one-bit switches with separate /OE inputs. When /OE is LOW, the switch is ON and port A is connected to port B. When /OE is HIGH, the switch is OPEN and a high-impedance state exists between the two 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

Application Notes