ST 74LCX74 User Manual

74LCX74

Low voltage CMOS dual D-Type Flip Flop with 5V tolerant inputs

Features

■5V tolerant inputs

■High speed:

–fMAX = 150MHz (Max) at VCC = 3V

■Power down protection on inputs and outputs

■Symmetrical output impedance:

–|IOH| = IOL = 24mA (Min) at VCC = 3V

■PCI bus levels guaranteed at 24mA

■Balanced propagation delays:

–tPLH tPHL

■Operating voltage range:

–VCC (Opr) = 2.0V to 3.6V

■Pin and function compatible with 74 series 74

■Latch-up performance exceeds 500mA (JESD 17)

■ESD performance:

–HBM > 2000V

(MIL STD 883 method 3015); MM > 200V

SO-14	TSSOP14

Description

The 74LCX74 is a low voltage CMOS dual D-type flip flop with preset and clear non inverting fabricated with sub-micron silicon gate and double-layer metal wiring C2MOS technology. It is ideal for low power and high speed 3.3V applications; it can be interfaced to 5V signal environment for inputs.

A signal on the D INPUT is transferred to the Q OUTPUT during the positive going transition of the clock pulse.

CLR and PR are independent of the clock and accomplished by a low setting on the appropriate input.

It has same speed performance at 3.3V than 5V AC/ACT family, combined with a lower power consumption.

All inputs and outputs are equipped with protection circuits against static discharge, giving them 2KV ESD immunity and transient excess voltage.

Order codes

Part number	Package	Packaging
74LCX74MTR	SO-14	Tape and reel
74LCX74TTR	TSSOP14	Tape and reel
July 2006	Rev 8	1/17
		www.st.com

Contents	74LCX74

Contents

1	Logic symbols and I/O equivalent circuit . . . . . . . . . . . . . . . . . . . . . . .		. 3
	1.1	Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	3
2	Pin settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		4
	2.1	Pin connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	4
	2.2	Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	4
	2.3	Truth table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	4
3	Maximum rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		5
	3.1	Recommended operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	5
4	Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		6
5	Test circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		8
6	Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		8
7	Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		11
8	Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		16

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74LCX74	Logic symbols and I/O equivalent circuit

1 Logic symbols and I/O equivalent circuit

Figure 1. IEC logic symbols

Figure 2. Input and output equivalent circuit

1.1Logic diagram

Figure 3. Logic diagram

Note:

This logic diagram has not to be used to estimate propagation delays

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Pin settings	74LCX74

2 Pin settings

2.1Pin connection

Figure 4. Pin connection (top through view)

2.2

Pin description

Table 1. Pin description

Pin N°

Symbol

Name and function

1, 13

Asynchronous reset - direct input

1CLR,

2CLR

2, 12

1D, 2D

Data inputs

3, 11

1CK, 2CK

Clock input (LOW to HIGH, Edge Triggered)

4, 10

Asynchronous set - direct input

1PR,

2PR

5, 9

1Q, 2Q

True Flip-Flop outputs

6, 8

Complement Flip-Flop outputs

1Q,

2Q

7

GND

Ground (0V)

14

VCC

Positive supply voltage

2.3

Truth table

Table 2. Truth table

Inputs

Outputs

Function

CLR

PR

D

CK

Q

Q

L

H

X

X

L

H

CLEAR

H

L

X

X

H

L

PRESET

L

L

X

X

H

H

H

H

L

L

H

H

H

H

H

L

H

H

X (1)

Qn

No change

Q

n

1. X do not care

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74LCX74	Maximum rating

3 Maximum rating

stressing the device above the rating listed in the “absolute maximum ratings” table may cause permanent damage to the device. these are stress ratings only and operation of the device at these or any other conditions above those indicated in the operating sections of this specification is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. refer also to the STMicroelectronics sure program and other relevant quality documents.

Table 3. Absolute maximum ratings

Symbol	Parameter	Value	Unit
VCC	Supply voltage	-0.5 to +7.0	V
VI	DC input voltage	-0.5 to +7.0	V
VO	DC output voltage (VCC = 0V)	-0.5 to +7.0	V
VO	DC output voltage (high or low state) (1)	-0.5 to VCC + 0.5	V
IIK	DC input diode current	-50	mA
IOK	DC output diode current (2)	-50	mA
IO	DC output current	± 50	mA
ICC	DC supply current per supply pin	± 100	mA
IGND	DC ground current per supply pin	± 100	mA
Tstg	Storage temperature	-65 to +150	°C
TL	Lead temperature (10 sec)	300	°C

1.IO absolute maximum rating must be observed

2.VO < GND

3.1Recommended operating conditions

Table 4. Recommended operating conditions

Symbol	Parameter	Value	Unit
VCC	Supply voltage (1)	2.0 to 3.6	V
VI	Input voltage	0 to 5.5	V
VO	Output voltage (VCC = 0V)	0 to 5.5	V
VO	Output voltage (high or low state)	0 to VCC	V
IOH, IOL	High or low level output current (VCC = 3.0 to 3.6V)	± 24	mA
IOH, IOL	High or low level output current (VCC = 2.7V)	± 12	mA
Top	Operating temperature	-40 to 85	°C
dt/dv	Input Rise and Fall Time(2)	0 to 10	ns/V

1.Truth table guaranteed: 1.5V to 3.6V

2.VIN from 0.8V to 2V at VCC = 3.0V

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Electrical characteristics	74LCX74

4 Electrical characteristics

Table 5. DC specifications

		Test condition		Value
Symbol	Parameter	VCC		-40 to 85°C			Unit
		(V)		Min		Max
VIH	High level input			2.0			V
	voltage
		2.7 to 3.6
VIL	Low level input					0.8	V
	voltage
		2.7 to 3.6	IO=-100 A	VCC-0.2
VOH	High level output	2.7	IO=-12 mA	2.2			V
	voltage		IO=-18 mA	2.4
		3.0
			IO=-24 mA	2.2
		2.7 to 3.6	IO=100 A			0.2
VOL	Low level output	2.7	IO=12 mA			0.4	V
	voltage		IO=16 mA			0.4
		3.0
			IO=24 mA			0.55
II	Input leakage current	2.7 to 3.6	VI = 0 to 5.5V			± 5	A
Ioff	Power OFF leakage	0	VI or VO = 5.5V			10	A
	current
ICC	Quiescent supply	2.7 to 3.6	VI = VCC or GND			10	A
	current		VI or VO= 3.6 to 5.5V			± 10
∆ICC	I incr. per Input	2.7 to 3.6	VIH = VCC - 0.6V			500	A

Table 6. Dynamic switching characteristics

			Test condition				Value
Symbol	Parameter	VCC				TA = 25 °C			Unit
		(V)				Min	Typ	Max
VOLP	Dynamic low level quiet	3.3		CL = 50pF			0.8		V
VOLV	output (1)			VIL = 0V, VIH	= 3.3V		-0.8

1.Number of outputs defined as "n". Measured with "n-1" outputs switching from HIGH to LOW or LOW to HIGH. The remaining output is measured in the LOW state.

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