Integrated Device Technology, Inc.
FAST CMOS OCTAL
• IDT54/74FCT245/640/645 equivalent to FAST™ speed
• IDT54/74FCT245A/640A/645A 25% faster than FAST
• IDT54/74FCT245C/640C/645C 40% faster than FAST
• TTL input and output level compatible
• CMOS output level compatible
• IOL = 64mA (commercial) and 48mA (military)
• Input current levels only 5µA max.
• CMOS power levels (2.5mW typical static)
• Direction control and over-riding 3-state control
• Product available in Radiation Tolerant and Radiation
• Military product compliant to MIL-STD-883, Class B and
• Meets or exceeds JEDEC Standard 18 specifications
The IDT octal bidirectional transceivers are built using an
advanced dual metal CMOS technology. The IDT54/
74FCT245/A/C, IDT54/74FCT640/A/C and IDT54/74FCT645/
A/C are designed for asynchronous two-way communication
between data buses. The transmit/receive (T/R) input deter-
mines the direction of data flow through the bidirectional
transceiver. Transmit (active HIGH) enables data from A
ports to B ports, and receive (active LOW) from B ports to A
ports. The output enable (OE) input, when HIGH, disables
both A and B ports by placing them in High-Z condition.
The IDT54/74FCT245/A/C and IDT54/74FCT645/A/C
transceivers have non-inverting outputs. The IDT54/
74FCT640/A/C has inverting outputs.
FUNCTIONAL BLOCK DIAGRAM
1. FCT245, 645 are noninverting options.
2. FCT640 is the inverting option.
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The IDT logo is a registered trademark of Integrated Device Technology, Inc.
FAST is a registered trademark of National Semiconductor Co.
MILITARY AND COMMERCIAL TEMPERATURE RANGES
©1992 Integrated Device Technology, Inc.
4 P20-1 17
6 & 15
7 E20-1 14
3 2 20 19
1 18 B0
A4 6 L20-2 16 B2
9 10 11 12 13
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