Octal Bus Transceiver
TC74HC245AP/AF 3-State, Non-Inverting
TC74HC640AP/AF 3-State, Inverting

The TC74HC245A, 640A are high speed CMOS OCTAL BUS TRANSCEIVERs fabricated with silicon gate C2MOS technology.
They achieve the high speed operation similar to equivalent LSTTL 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 (Note 1)(Note 2)
• High speed: tpd = 10 ns (typ.) at VCC = 5 V
• Low power dissipation: ICC = 4 μA (max) at Ta = 25°C
• High noise immunity: VNIH = VNIL = 28% VCC (min)
• Output drive capability: 15 LSTTL loads
• Symmetrical output impedance: |IOH| = IOL = 6 mA (min)
• Balanced propagation delays: tpLH ∼ − tpHL
• Wide operating voltage range: VCC (opr) = 2 to 6 V
• Pin and function compatible with 74LS245/640