Texas Instruments CY74FCT191CTSOCT, CY74FCT191CTSOC, CY74FCT191CTQCT, CY74FCT191CTQC, CY74FCT191ATSOCT Datasheet

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

SCCS016 - May 1994 - Revised February 2000

CY74FCT191T

4-Bit Up/Down Binary Counter

Features

•Function, pinout, and drive compatible with FCT and F logic

•FCT-C speed at 6.2 ns max,

FCT-A speed at 7.8 ns max.

• Reduced V (typically = 3.3V) versions of equivalent

OH

FCT functions

•Edge-rate control circuitry for significantly improved noise characteristics

•Power-off disable permits live insertion

•ESD > 2000V

•Matched rise and fall times

Functional Description

The FCT191T is a reversible modulo-16 binary counter, featuring synchronous counting and asynchronous presetting. The preset allows the FCT191T to be used in programmable dividers. The count enable input, terminal count output, and ripple clock output make possible a variety of methods of implementing multiusage counters. In the counting modes, state changes are initiated by the rising edge of the clock.

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

• Sink current	64 mA
Source current	32 mA

Logic Block Diagram						Pin Configurations
CP U/D	P0	CE	P1	P2	P3	PL
							SOIC/QSOP
								Top View
						P1	1	16	VCC
						Q1	2	15	P0
						Q0	3	14	CP
						CE	4	13	RC
						U/D	5	12	TC
						Q2	6	11	PL
						Q3	7	10	P2
						GND	8	9	P3

J CLOCK K		J CLOCK K		J CLOCK K		J CLOCK K
PRESET		PRESET		PRESET		PRESET
	CLEAR		CLEAR		CLEAR		CLEAR
Q	Q	Q	Q	Q	Q	Q	Q

			Q1
RC TC		Q0		Q2	Q3

Pin Description

		Name					Description
							Count Enable Input (Active LOW)
		CE
	CP						Clock Pulse Input (Active Rising Edge)
	P						Parallel Data Inputs
							Asynchronous Parallel Load Input (Active LOW)
	PL
							Up/Down Count Control Input
	U/D
	Q						Flip-Flop Outputs
							Ripple Clock Output (Active LOW)
	RC
	TC						Terminal Count Output

RC Function Table[1]

Inputs

Outputs

CP

T[2]

CE

RC

L

H

H

X

X

H

X

X

L

H

Copyright © 2000, Texas Instruments Incorporated

CY74FCT191T

RC Function Table[1]

		Inputs				Outputs
				CP	T[2]
	CE							RC

Notes:

1.H = HIGH Voltage Level, L = LOW Voltage Level, X = Don‘t Care,

			= LOW-to-HIGH clock transition.				=Low Pulse.
2. TC is generated internally.

Mode Select[1]

Inputs

CP

Mode

PL

CE

U/D

H

L

L

Count Up

H

L

H

Count Down

L

X

X

X

Preset (Asynchronous)

H

H

X

X

No Change (Hold)

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
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	Temperature	VCC
Commercial	–40°C to +85°C	5V ± 5%

Maximum Ratings[3, 4]

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

Storage Temperature .................................–65°C to +150°C

Electrical Characteristics Over the Operating Range

Parameter		Description		Test Conditions	Min.	Typ.[5]	Max.	Unit
VOH		Output HIGH Voltage	VCC=Min., IOH=–32 mA		2.0			V
			VCC=Min., IOH=–15 mA		2.4	3.3		V
VOL		Output LOW Voltage	VCC=Min., IOL=64 mA			0.3	0.55	V
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	A
IIH		Input HIGH Current	VCC=Max., VIN=2.7V				±1	A
IIL		Input LOW Current	VCC=Max., VIN=0.5V				±1	A
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	A

Capacitance[6]

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

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

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

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.

2