General-purpose mux offers an internal injection current control feature

03-08-2020 | Texas Instruments | Connectors, Switches & EMECH

The Texas Instruments TMUX1308 and TMUX1309 are general-purpose CMOS mux. The TMUX1308 is an 8:1, one-channel (single-ended) mux, while the TMUX1309 is a 4:1, two-channel (differential) mux. The devices offer bidirectional analog and digital signals on the source (Sx) and drain (Dx) pins extending from GND to VDD.

The devices offer an internal injection current control feature which removes the requirement for external diode and resistor networks often employed to defend the switch and retain the input signals within the supply voltage. The internal injection current control circuitry enables signals on disabled signal paths to surpass the supply voltage without affecting the signal of the enabled signal path. Furthermore, the devices do not possess any internal diode path to the supply pin, which removes the risk of damaging components connected to the supply pin or giving unintended power to the supply rail.

All logic inputs provide 1.8V logic compatible thresholds, assuring both TTL and CMOS logic compatibility when running with a valid supply voltage. Fail-Safe Logic circuitry enables voltages on the control pins to be implemented before the supply pin, shielding the device from potential damage.

By Natasha Shek