Philips 74HCT7540U, 74HCT7540D, 74HC7540U, 74HC7540N, 74HC7540DB Datasheet

INTEGRATED CIRCUITS

DATA SHEET

For a complete data sheet, please also download:

∙The IC06 74HC/HCT/HCU/HCMOS Logic Family Specifications

∙The IC06 74HC/HCT/HCU/HCMOS Logic Package Information

∙The IC06 74HC/HCT/HCU/HCMOS Logic Package Outlines

74HC/HCT7540

Octal Schmitt trigger buffer/line driver; 3-state; inverting

Product specification			December 1990
Supersedes data of March 1988
File under Integrated Circuits, IC06

Philips Semiconductors	Product specification

Octal Schmitt trigger buffer/line driver;

74HC/HCT7540

3-state; inverting

FEATURES

·Inverting outputs

·Schmitt trigger action on all data inputs

·Output capability: bus driver

·ICC category: MSI

GENERAL DESCRIPTION

The 74HC/HCT7540 are high-speed Si-gate CMOS devices and are pin compatible with low power Schottky TTL (LSTTL). They are specified in compliance with JEDEC standard no. 7A.

QUICK REFERENCE DATA

GND = 0 V; Tamb = 25 °C; tr = tf = 6 ns

The 74HC/HCT7540 are octal Schmitt trigger inverting buffer/line drivers with 3-state outputs. The 3-state outputs are controlled by the output enable inputs OE1 and OE2.

A HIGH on OEn causes the outputs to assume a high impedance OFF-state.

The Schmitt trigger action in the data inputs transforms slowly changing input signals into sharply defined jitter-free output signals.

The “7540” is identical to the “540” but has hysteresis on the data inputs.

SYMBOL	PARAMETER			CONDITIONS		TYPICAL		UNIT
					HC		HCT
tPHL/ tPLH	propagation delay An to		n	CL = 15 pF; VCC = 5 V	11		16	ns
		Y
CI	input capacitance				3.5		3.5	pF
CPD	power dissipation capacitance per buffer			notes 1 and 2	29		31	pF

Notes

1. CPD is used to determine the dynamic power dissipation (PD in mW): PD = CPD ´ VCC2 ´ fi + å (CL ´ VCC2 ´ fo) where:

fi = input frequency in MHz fo = output frequency in MHz

å (CL ´ VCC2 ´ fo) = sum of outputs CL = output load capacitance in pF VCC = supply voltage in V

2. For HC the condition is VI = GND to VCC

For HCT the condition is VI = GND to VCC - 1.5 V

ORDERING INFORMATION

See “74HC/HCT/HCU/HCMOS Logic Package Information”.

December 1990

2

Philips Semiconductors	Product specification

Octal Schmitt trigger buffer/line driver;

74HC/HCT7540

3-state; inverting

PIN DESCRIPTION

PIN NO.		SYMBOL							NAME AND FUNCTION
1, 19				1,				2	output enable inputs (active LOW)
		OE			OE
2, 3, 4, 5, 6, 7, 8, 9		A0 to A7							data inputs
10		GND							ground (0 V)
18, 17, 16, 15, 14, 13, 12, 11							7		bus outputs
		Y	0 to			Y
20		VCC							positive supply voltage

Fig.1 Pin configuration.		Fig.2 Logic symbol.		Fig.3 IEC logic symbol.

December 1990

3