Fairchild Semiconductor 74LCX245MTCX, 74LCX245MTC, 74LCX245MSAX, 74LCX245MSA, 74LCX245CW Datasheet

February 1994
Revised May 1999

74LCX245 Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs

© 1999 Fairchild Semiconductor Corporation DS012006.prf www.fairchildsemi.com

74LCX245
Low Voltage Bidirectional Transceiver with 5V Tolerant

Inputs and Outputs

General Description

The LCX245 contains eight non-inverting bidirectional buff­ers with 3-STATE outputs and is intended for bus ori ented
applications. The device is desi gned for low voltage (2.5V
and 3.3V) V

CC

applications with capability of interfacing to

a 5V signal environment. The T/R

input determines the

direction of data flow through the device. The OE

input dis­ables both the A and B ports by placing them in a h igh
impedance state.

The LCX245 is fabrica ted with an advanced CMOS tech­nology to achieve high spee d operation while mai ntaining
CMOS low power dissipation.

Features

■ 5V tolerant inputs and outputs

■ 2.3V–3.6V V

CC

specifications provided

■ 7.0 ns t

PD

max (V

CC

= 3.3V), 10 µA ICC max

■ Power down high impedance inputs and outputs

■ Supports live insertion/withdrawal (Note 1)

■ ±24 mA output drive (V

CC

= 3.0V)

■ Implements patented noise/EMI reduction circuitry

■ Latch-up performance exceeds 500 mA

■ ESD performance:

Human body model > 2000V
Machine model > 200V

Note 1: To ensure the high-impedan c e state during power up or down, OE
should be tied to VCC through a pull-up res istor: the m inimu m value or t he

resistor is determin ed by the current-sourcing capability of the driver.

Ordering Code:

Devices also availab le in Tape and Reel. Specify by appending th e s uffix let t er “X” to the ordering cod e.

Logic Symbol

Pin Descriptions

Connection Diagram

Order Number Package Number Package Description

74LCX245WM M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300” Wide
74LCX245SJ M20D 20-Lead Small Outline Package (SOP), EIAJ Type II, 4.4mm Wide
74LCX245MSA MSA20 20-Lead Shrink Small Outline Package (SSOP), EIAJ Type II, 5.3mm Wide
74LCX245MTC MTC20 20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide

Pin Names Description

OE

Output Enable Input

T/R

Transmit/Receive Input

A

0–A7

Side A Inputs or 3-STATE Outputs

B

0–B7

Side B Inputs or 3-STATE Outputs

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74LCX245

Truth Table

H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
Z = High Impedance

Note 2: Unused bu s ter m inals during HIGH Z Stat e m ust be held HIGH or LOW.

Logic Diagram

Inputs Outputs

OE

T/R

L L Bus B0 – B7 Data to Bus A0 – A

7

L H Bus A0 – A7 Data to Bus B0 – B

7

H X HIGH Z State on A0 – A7, B0 – B7 (Note 2)

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74LCX245

Absolute Maximum Ratings(Note 3)

Recommended Operating Conditions (Note 5)

Note 3: The Absolute Maximum Ratings are those values beyond which the safety of the device cannot be guaranteed. The device should not be operated

at these limits. The parametric values defined in the Electrical Characteristics tables are not guaranteed at the Absolute Maximum Ratings. The “Recom­mended Operating C onditions” table will def ine the conditions for ac t ual device operation.

Note 4: I

O

Absolute Maximum Rating must be observed.

Note 5: Unused inputs or I/O pins must be held HIGH or LOW. They may not float.

DC Electrical Characteristics

Symbol Parameter Value Conditions Units

V

CC

Supply Voltage −0.5 to +7.0 V

V

I

DC Input Voltage −0.5 to +7.0 V

V

O

DC Output Voltage −0.5 to +7.0 Output in 3-STATE

V

−0.5 to V

CC

+ 0.5 Output in HIGH or LOW State (Note 4)

I

IK

DC Input Diode Current −50 VI < GND mA

I

OK

DC Output Diode Current −50 VO < GND

mA

+50 V

O

> V

CC

I

O

DC Output Source/Sink Current ±50 mA

I

CC

DC Supply Current per Supply Pin ±100 mA

I

GND

DC Ground Current per Ground Pin ±100 mA

T

STG

Storage Temperature −65 to +150 °C

Symbol Parameter Min Max Units

V

CC

Supply Voltage Operating 2.0 3.6

V

Data Retention 1.5 3.6

V

I

Input Voltage 05.5V

V

O

Output Voltage HIGH or LOW State 0 V

CC

V

3-STATE 0 5.5

I

OH/IOL

Output Current VCC = 3.0V − 3.6V ±24

mAV

CC

= 2.7V - 3.0V ±12

V

CC

= 2.3V - 2.7V ±8

T

A

Free-Air Operating Temperature −40 85 °C

∆t/∆V Input Edge Rate, V

IN

= 0.8V − 2.0V, VCC = 3.0V 0 10 ns/V

Symbol Parameter Conditions

V

CC

TA = −40°C to +85°C

Units

(V) Min Max

V

IH

HIGH Level Input Voltage 2.3 − 2.7 1.7

V

2.7 − 3.6 2.0

V

IL

LOW Level Input Voltage 2.3 − 2.7 0.7

V

2.7 - 3.6 0.8

V

OH

HIGH Level Output Voltage IOH = −100 µA 2.3 - 3.6 VCC − 0.2

V

IOH = −8 mA 2.3 1.8
IOH = −12 mA 2.7 2.2
IOH = −18 mA 3.0 2.4
IOH = −24 mA 3.0 2.2

V

OL

LOW Level Output Voltage IOL = 100 µA2.3 − 3.6 0.2

V

IOL = 8mA 2.3 0.6
IOL = 12 mA 2.7 0.4
IOL = 16 mA 3.0 0.4
IOL = 24 mA 3.0 0.55

I

I

Input Leakage Current 0 ≤ VI ≤ 5.5V 2.3 − 3.6 ±5.0 µA

I

OZ

3-STATE I/O Leakage 0 ≤ VO ≤ 5.5V 2.3 − 3.6 ±5.0 µA

VI = VIH or V

IL

I

OFF

Power-Off Leakage Current VI or VO = 5.5V 0 10 µA