Octal Bus Transceiver

TC74AC245P/F/FT 3-State, Non-Inverting

TC74AC640P/F/FT 3-State, Inverting

The TC74AC245, 640 are advanced high speed CMOS OCTAL BUS TRANSCEIVERs fabricated with silicon gate and double-layer metal wiring C2MOS technology. They achieve the high speed operation similar to equivalent Bipolar Schottky TTL while maintaining the CMOS low power

dissipation. They are intended for two-way asynchronous communication between data busses. The direction of data transmission is determined by the level of the DIR input. The enable input (G) can be used to disable the device so that the busses are effectively isolated. All inputs are equipped with protection circuits against static discharge or transient excess voltage.

Features

• High speed: tpd = 3.9 ns (typ.) at VCC = 5 V

• Low power dissipation: ICC = 8 μA (max) at Ta =25°C

• High noise immunity: VNIH = VNIL =28% VCC(min)

• Symmetrical output impedance:

|IOH| =IOL = 24 mA (min)

Capability of driving 50 Ωtransmission lines.

• Balanced propagation delays: tpLH

∼  − tpHL

• Wide operating voltage range: VCC(opr) =2 V to 5.5 V

• Pin and function compatible with 74F245/640