Document
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVERS
Integrated Device Technology, Inc.
IDT54/74FCT245T/AT/CT/DT - 2245T/AT/CT IDT54/74FCT640T/AT/CT IDT54/74FCT645T/AT/CT/DT
FEATURES:
• Common features: – Low input and output leakage ≤1µA (max.) – CMOS power levels – True TTL input and output compatibility – VOH = 3.3V (typ.) – VOL = 0.3V (typ.) – Meets or exceeds JEDEC standard 18 specifications – Product available in Radiation Tolerant and Radiation Enhanced versions – Military product compliant to MIL-STD-883, Class B and DESC listed (dual marked) – Available in DIP, SOIC, SSOP, QSOP, CERPACK and LCC packages • Features for FCT245T/FCT640T/FCT645T: – Std., A, C and D speed grades – High drive outputs (-15mA IOH, 64mA IOL) • Features for FCT2245T: – Std., A and C speed grades – Resistor outputs (-15mA IOH, 12mA IOL Com.) (-12mA IOH, 12mA IOL Mil.) – Reduced system switching noise
DESCRIPTION:
The IDT octal bidirectional transceivers are built using an advanced dual metal CMOS technology. The FCT245T/ FCT2245T, FCT640T and FCT645T are designed for asynchronous two-way communication between data buses. The transmit/receive (T/R) input determines 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 FCT245T/FCT2245T and FCT645T transceivers have non-inverting outputs. The FCT640T has inverting outputs. The FCT2245T has balanced drive outputs with current limiting resistors. This offers low ground bounce, minimal undershoot and controlled output fall times- reducing the need for external series terminating resistors. The FCT2xxxT parts are plug-in replacements for FCTxxxT parts.
FUNCTIONAL BLOCK DIAGRAM
T/R OE A0 B0 A1 B1 A2 B2 A3 B3 A4 B4 A5 B5 A6 B6 A7 B7
FCT245T/2245T, FCT645T are non-inverting options. FCT640T is the inverting options.
2539 drw 01 The IDT logo is a registered trademark of Integrated Device Technology, Inc.
PIN CONFIGURATIONS
T/R A0 A1 A2 A3 A4 A5 A6 A7 GND
1 2 3 4 5 6 7 8 9 10 20 19
P20-1 D20-1 SO20-2 SO20-7* SO20-8** & E20-1
18 17 16 15 14 13 12 11
Vcc OE B0 B1 B2 B3 B4 B5 B6 B7
2539 drw 02
DIP/SOIC/SSOP/QSOP/CERPACK TOP VIEW *FCT245T/2245T, FCT645T only. **FCT245T/2245T, FCT640T
INDEX
A2 A3 A4 A5 A6
A1 A0 T/R Vcc OE
3 4 5 6 7 8 2 1 20 19 18 17 16 15 14 9 10 11 12 13
L20-2
B0 B1 B2 B3 B4
A7 GND B7 B6 B5
2539 drw 03
LCC TOP VIEW
MILITARY AND COMMERCIAL TEMPERATURE RANGES
©1995 Integrated Device Technology, Inc.
AUGUST 1995
DSC-4611/4
6.9
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IDT54/74FCT245T/AT/CT/DT - 2245T/AT/CT, IDT54/74FCT640T/AT/CT, IDT54/74FCT645T/AT/CT/DT FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVERS MILITARY AND COMMERCIAL TEMPERATURE RANGES
PIN DESCRIPTION
Pin Names
FUNCTION TABLE(2)
Inputs
OE T/R
A0-A7 B0-B7
Description Output Enable Input (Active LOW) Transmit/Receive Input Side A Inputs or 3-State Outputs Side B Inputs or 3-State Outputs
2539 tbl 01
OE
L L H
T/R L H X
Outputs Bus B Data to Bus A(1) Bus B Data to Bus B(1) High Z State
2539 tbl 02
NOTES: 1. 640 is inverting from input to output. 2. H = HIGH Voltage Level L = LOW Voltage Level X = Don't Care
ABSOLUTE MAXIMUM RATINGS(1)
Symbol Rating Commercial VTERM(2) Terminal Voltage –0.5 to +7.0 with Respect to GND VTERM(3) Terminal Voltage –0.5 to with Respect to VCC +0.5 GND TA Operating 0 to +70 Temperature TBIAS Temperature –55 to +125 Under Bias TSTG Storage –55 to +125 Temperature PT Power Dissipation 0.5 I OUT DC Output Current –60 to +120 Military –0.5 to +7.0 Unit V
CAPACITANCE (TA = +25°C, F = 1.0MHZ)
Symbol Parameter(1) CIN Input Capacitance COUT Output Capacitance Conditions VIN = 0V VOUT = 0V Typ. 6 8 Max. Unit 10 pF 12
pF
2539 lnk 04
–0.5 to VCC +0.5 –55 to +125 –65 to +135 –65 to +150 0.5 –60 to +120
V °C °C °C W mA
NOTE: 1. This parameter is measured at characterization but not tested.
2539 lnk 03 NOTES: 1. Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. No terminal voltage may exceed VCC by +0.5V unless otherwise noted. 2. Input and VCC terminals only. 3. Outputs and I/O terminals only.
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IDT54/74FCT245T/AT/CT/DT - 2245T/AT/CT, IDT54/74FCT640T/AT/CT, IDT54/74FCT645T/AT/CT/DT FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVERS MILITARY AND COMMERCIAL TEMPERATURE RANGES
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified: Commercial: TA = 0°C to +70°C, VCC = 5.0V ± 5%; Military: TA = –55°C to +125°C, VCC = 5.0V ± 10%
Symbol VIH VIL II H II L I OZH I OZL II VIK VH I CC Parameter Input HIGH Level Input LOW Level I.