Texas Instruments CY74FCT2245TSOCT, CY74FCT2245TSOC, CY74FCT2245TQCT, CY74FCT2245TQC, CY74FCT2245CTSOCT Datasheet

Data sheet acquired from Cypress Semiconductor Corporation. Data sheet modified to remove devices not offered.

SCCS037 - July 1994 - Revised March 2000

CY74FCT2245T

8-Bit Transceiver

Features

•Function and pinout compatible with FCT and F logic

•25Ω output series resistors to reduce transmission line reflection noise

•FCT-C speed at 4.1 ns max. FCT-A speed at 4.6 ns max.

•Edge-rate control circuitry for significantly improved noise characteristics

•Power-off disable feature

•Fully compatible with TTL input and output logic levels

•ESD > 2000V

• Sink current	12 mA
Source current	15 mA

•Extended commercial temp. range of –40˚C to +85˚C

•Three-state outputs

Functional Description

The FCT2245T contains eight non-inverting, bidirectional buffers with three-state outputs intended for bus oriented applications. On-chip termination resistors have been added to the outputs to reduce system noise caused by reflections. For this reason, the FCT2245T can be used in an existing design to replace the FCT245T. The FCT2245T current sinking capability is 12 mA at the A and B ports.

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; receive (Active LOW) enables data from B ports to A ports. The output enable (OE) input, when HIGH, disables both the A and B ports by putting them in a High Z condition.

The outputs are designed with a power-off disable feature to allow for live insertion of boards.

Logic Block Diagram			Pin Configurations
	T/R
		OE		DIP/SOIC/QSOP
	A0			Top View
		B0	T/R	1	20	VCC
	A1		A0	2	19	OE
					18
		B1	A1	3		B0
			A2	4	17	B1
	A2		A3	5	16	B2
		B2	A4	6	15	B3
					14
	A3		A5	7		B4
			A6	8	13	B5
		B3	A7	9	12	B6
	A4		GND	10	11	B7
		B4			FCT2245T–3
	A5
		B5
	A6
		B6
	A7
		B7
	FCT2245T–1
Function Table[1]
	Inputs
OE	T/R	Output
L	L	Bus B Data to Bus A
L	H	Bus A Data to Bus B
H	X	High Z State
Note:

1.H = HIGH Voltage Level. L = LOW Voltage Level. X = Don’t Care.

Copyright © 2000, Texas Instruments Incorporated

CY74FCT2245T

Maximum Ratings[2,3]

(Above which the useful life may be impaired. For user guidelines, not tested.)

Storage Temperature .................................	–65°C to +150°C
Ambient Temperature with	–65°C to +135°C
Power Applied .............................................
Supply Voltage to Ground Potential ...............	–0.5V to +7.0V
DC Input Voltage............................................	–0.5V to +7.0V
DC Output Voltage .........................................	–0.5V to +7.0V

Electrical Characteristics Over the Operating Range

DC Output Current (Maximum Sink Current/Pin) ......	120 mA
Power Dissipation ..........................................................	0.5W
Static Discharge Voltage............................................	>2001V

(per MIL-STD-883, Method 3015)

Operating Range

		Ambient
Range	Range	Temperature	VCC
Commercial	T, AT, CT	–40°C to +85°C	5V ± 5%

Parameter		Description		Test Conditions		Min.	Typ.[5]	Max.	Unit
VOH		Output HIGH Voltage	VCC=Min., IOH=–15 mA		Com’l	2.4	3.3		V
VOL		Output LOW Voltage	VCC=Min., IOL=12 mA		Com’l		0.3	0.55	V
ROUT		Output Resistance	VCC=Min., IOL=12 mA		Com’l	20	25	40	Ω
VIH		Input HIGH Voltage				2.0			V
VIL		Input LOW Voltage						0.8	V
VH		Hysteresis[6]	All inputs				0.2		V
VIK		Input Clamp Diode Voltage	VCC=Min., IIN=–18 mA				–0.7	–1.2	V
II		Input HIGH Current	VCC=Max., VIN=VCC					5	µA
IIH		Input HIGH Current	VCC=Max., VIN=2.7V					±1	µA
IIL		Input LOW Current	VCC=Max., VIN=0.5V					±1	µA
I	OS	Output Short Circuit Current[7]	V	=Max., V =0.0V		–60	–120	–225	mA
			CC	OUT
IOFF		Power-Off Disable	VCC=0V, VOUT=4.5V					±1	µA

Capacitance[6]

Parameter	Description	Test Conditions	Typ.[5]	Max.	Unit
CIN	Input Capacitance		5	10	pF
COUT	Output Capacitance		9	12	pF
Notes:

2.Unless otherwise noted, these limits are over the operating free-air temperature range.

3.Unused inputs must always be connected to an appropriate logic voltage level, preferably either VCC or ground.

4.TA is the “instant on” case temperature.

5.Typical values are at VCC=5.0V, TA=+25˚C ambient.

6.This parameter is specified but not tested.

7.Not more than one output should be shorted at a time. Duration of short should not exceed one second. The use of high-speed test apparatus and/or sample and hold techniques are preferable in order to minimize internal chip heating and more accurately reflect operational values. Otherwise prolonged shorting of a high output may raise the chip temperature well above normal and thereby cause invalid readings in other parametric tests. In any sequence of parameter tests, IOS tests should be performed last.

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CY74FCT2245T

Power Supply Characteristics

Parameter	Description			Test Conditions	Typ.[5]	Max.	Unit
ICC	Quiescent Power Supply Current	VCC=Max., VIN < 0.2V,			0.1	0.2	mA
		VIN > VCC–0.2V
ICC	Quiescent Power Supply Current	VCC=Max., VIN=3.4V,[8]			0.5	2.0	mA
	(TTL inputs)	f1=0, Outputs Open
ICCD	Dynamic Power Supply	VCC=Max., One Input Toggling,			0.06	0.12	mA/MHz
	Current[9]	50% Duty Cycle, Outputs Open,
		T/R=OE=GND,
		VIN < 0.2V or VIN > VCC–0.2V
IC	Total Power Supply Current[10]	VCC=Max., 50% Duty Cycle,			0.7	1.4	mA
		Outputs Open,
		One Bit Toggling at f1=10 MHz,
		T/R=OE=GND,
		VIN < 0.2V or VIN > VCC–0.2V
		VCC=Max.,			1.0	2.4	mA
		50% Duty Cycle, Outputs Open,
		One Bit Toggling at f1=10 MHz,
		T/R=OE=GND,
		VIN=3.4V or VIN=GND
		VCC=Max.,			1.3	2.6[11]	mA
		50% Duty Cycle, Outputs Open,
		Eight	Bits Toggling at f1=2.5 MHz,
		T/R=OE=GND,
		VIN < 0.2V or VIN > VCC–0.2V
		VCC=Max.,			3.3	10.6[11]	mA
		50% Duty Cycle, Outputs Open,
		Eight	Bits Toggling at f1=2.5 MHz,
		T/R=OE=GND,
		VIN=3.4V or VIN=GND
Notes:

8.Per TTL driven input (VIN=3.4V); all other inputs at VCC or GND.

9.This parameter is not directly testable, but is derived for use in Total Power Supply calculations.

10. IC	= IQUIESCENT + IINPUTS + IDYNAMIC
IC	= ICC+ ICCDHNT+ICCD(f0/2 + f1N1)
ICC	= Quiescent Current with CMOS input levels
ICC	= Power Supply Current for a TTL HIGH input (VIN=3.4V)
DH	= Duty Cycle for TTL inputs HIGH
NT	= Number of TTL inputs at DH
ICCD	= Dynamic Current caused by an input transition pair (HLH or LHL)
f0	= Clock frequency for registered devices, otherwise zero
f1	= Input signal frequency
N1	= Number of inputs changing at f1

All currents are in milliamps and all frequencies are in megahertz.

11. Values for these conditions are examples of the ICC formula. These limits are specified but not tested.

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