5-Ω Switch Connection Between Two Ports
TTL-Compatible Input Levels
Bus Hold on Data Inputs/Outputs
Eliminates the Need for External
Pullup/Pulldown Resistors

description
The SN74CBTH16211 provides 24 bits of
high-speed TTL-compatible bus switching. The
low on-state resistance of the switch allows
connections to be made with minimal propagation
delay.
The device is organized as dual 12-bit bus
switches with separate output-enable (OE)
inputs. It can be used as two 12-bit bus switches
or one 24-bit bus switch. When OE is low, the
associated 12-bit bus switch is on, and the A port
is connected to the B port. When OE is high, the
switch is open, and a high-impedance state exists
between the two ports.
Active bus-hold circuitry is provided to hold
unused or floating A and B ports at a valid logic
level.
To ensure the high-impedance state during power
up or power down, OE should be tied to VCC
through a pullup resistor; the minimum value of
the resistor is determined by the current-sinking
capability of the driver.