The TC74HC640AF(EL,F) is a high-speed CMOS octal bus transceiver with three-state outputs manufactured by Toshiba Semiconductor and Storage. It is fabricated with silicon gate CMOS technology, achieving high-speed operation similar to equivalent Schottky TTL while maintaining the low power dissipation characteristic of CMOS. This device is designed for asynchronous two-way communication between data buses.

Applications

• Bidirectional bus transceivers
• Memory interface
• Microprocessor systems
• Peripheral interface
• Data bus isolation

Features

• High-speed operation: tpd = 13 ns (typ.) at VCC = 5V
• 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 = 2 V to 6 V
• Three-state outputs for bus-oriented applications
• Direction control pin for controlling data flow

Benefits

• High-speed performance enables use in demanding data transfer applications.
• Low power consumption reduces power requirements, useful in battery-powered systems.
• High noise immunity provides reliable data transfer even in noisy environments.
• Large output drive capability allows direct connection to multiple devices on the bus.
• Wide operating voltage range makes it suitable for a variety of applications.
• Three-state outputs facilitate easy bus sharing and isolation.
• Direction control pin offers flexible data flow control.

Additional Details

The TC74HC640AF(EL,F) consists of eight transceivers with three-state outputs. The direction of data flow is controlled by the DIR input. When DIR is LOW, data flows from A to B. When DIR is HIGH, data flows from B to A. The output enable (OE) input, when HIGH, disables both A and B outputs, placing them in a high-impedance state. This allows for bus isolation. The (EL, F) suffix likely pertains to the specific packaging and reel options.

The operating temperature range is typically -40°C to +85°C. The package is a SOP20.