ST 74LCX125 User Manual

74LCX125

Low-voltage CMOS quad bus buffer (3-state) with 5 V tolerant inputs and outputs

Datasheet − production data

Features

■ 5 V tolerant inputs and outputs

■ High speed

– tPD = 5.2 ns (max) at VCC = 3 V

■ Power-down protection on inputs and outputs

■ Symmetrical output impedance TSSOP14 SO-14

– |IOH| = IOL = 24 mA (min) at VCC = 3 V

■PCI bus levels guaranteed at 24 mA

■Balanced propagation delay

–tPLH tPHL

■Operating voltage range

–VCC (opr) = 2.0 V to 3.6 V

■Pin and function compatible with 74 series 125

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

■ESD performance

–HBM > 2000V

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

Applications

■Automotive

■Industrial

■Computer

■Consumer

Table 1. Device summary

Description

The 74LCX125 is a low-voltage CMOS quad bus buffer manufactured with sub-micron silicon gate and double-layer metal wiring C2MOS technology. It is ideal for low-power and high-speed 3.3 V applications and can be interfaced to a 5 V signal environment for both inputs and outputs.

The device requires the 3-state control input G to be set high to place the output in the high impedance state.

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

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

Part number	Temperature range	Package	Packaging
74LCX125TTR	-40/+85 °C	TSSOP14	Tape and reel
74LCX125YTTR(1)	-40/+125 °C	TSSOP14 (automotive grade)	Tape and reel
74LCX125MTR	-40/+85 °C	SO-14	Tape and reel

1.Qualification and characterization (according to AEC Q100 and Q003 or equivalent) and advanced screening (according to AEC Q001 and Q002 or equivalent) are ongoing.

June 2012

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This is information on a product in full production.

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Contents	74LCX125

Contents

1	Logic symbols and I/O equivalent circuit . . . . . . . . . . . . . . . . . . . . . . .		. 3
2	Pin settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		4
	2.1	Pin connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	4
	2.2	Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	4
	2.3	Truth table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	4
3	Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		5
	3.1	Recommended operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	5
4	Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		6
5	Test circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		8
6	Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		9
7	Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		10
8	Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		15

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74LCX125	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

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Pin settings	74LCX125

2 Pin settings

2.1Pin connections

Figure 3. Pin connections (top through view)

2.2Pin description

Table 2.	Pin description
Pin number			Symbol				Name and function
1, 4, 10, 13							Output enable input
		1G		TO 4G
2, 5, 9, 12		1A		TO 4A			Data inputs
3, 6, 8, 11		1Y		TO 4Y			Data outputs
	7		GND				Ground (0 V)
	14			VCC			Positive supply voltage

2.3Truth table

Table 3.	Truth table
		Inputs				Output
	A					Y
				G
	X (1)			H		Z (2)
	L			L		L
	H			L		H

1.Do not care

2.High impedance

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74LCX125	Maximum ratings

3 Maximum ratings

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.

Table 4.	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 = 0 V)	-0.5 to +7.0	V
V	DC output voltage (high or low state) (1)	-0.5 to V + 0.5	V
O		CC
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 5.	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 = 0 V)		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 3.6 V)		± 24	mA
	IOH, IOL	High or low level output current (VCC = 2.7 V)		± 12	mA
	Top	Operating temperature	TSSOP14, SO-14	-40 to 85	°C
			TSSOP14 (automotive grade)	-40 to 125	°C
	dt/dv	Input rise and fall time (2)		0 to 10	ns/V

1.Truth table guaranteed: 1.5 V to 3.6 V

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

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