Fairchild 74LC244 service manual

74LCX244
Low Voltage Buffer/Line Driver with 5V Tolerant
Inputs and Outputs

74LCX244 — Low Voltage Buffer/Line Driver with 5V Tolerant Inputs and Outputs

February 2009

Features

■ 5V tolerant inputs and outputs

■ 2.3V to 3.6V V

■ 6.5ns t

■ Power down high impedance inputs and outputs

■ Supports live insertion/withdrawal

■ ±24mA output drive (V

■ Implements proprietary noise/EMI reduction circuitry

■ Latch-up performance exceeds 500mA

■ ESD performance:

– Human body model > 2000V
– Machine model > 200V

■ Leadless DQFN package

Note:

1. To ensure the high-impedance state during power up
or down, OE should be tied to VCC through a pull-up
resistor: the minimum value or the resistor is
determined by the current-sourcing capability of the
driver.

max. (VCC = 3.3V), 10µA ICC max.

PD

specifications provided

CC

= 3.0V)

CC

(1)

Ordering Information

General Description

The LCX244 contains eight non-inverting buffers with
3-STATE outputs. The device may be employed as a
memory address driver, clock driver and bus-oriented
transmitter/receiver. The LCX244 is designed for low
voltage (2.5V or 3.3V) V
interfacing to a 5V signal environment.

The LCX244 is fabricated with an advanced CMOS tech­nology to achieve high speed operation while maintain­ing CMOS low power dissipation.

applications with capability of

CC

Package

Order Number

74LCX244WM

74LCX244SJ

74LCX244BQX

74LCX244MSA MSA20 20-Lead Shrink Small Outline Package (SSOP), JEDEC MO-150, 5.3mm Wide

74LCX244MTC

Note:

2. DQFN package available in Tape and Reel only.

Device also available in Tape and Reel. Specify by appending suffix letter “X” to the ordering number.

All packages are lead free per JEDEC: J-STD-020B standard.

©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX244 Rev. 1.12.1

(2)

Number Package Description

M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300" Wide

M20D 20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide

MLP20B

MTC20

20-Terminal Depopulated Quad Very-Thin Flat Pack No Leads (DQFN),
JEDEC MO-241, 2.5 x 4.5mm

20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153,

4.4mm Wide

74LCX244 — Low Voltage Buffer/Line Driver with 5V Tolerant Inputs and Outputs

Connection Diagram

Pin Assignments for SOIC, SOP, SSOP, and TSSOP

Pad Assignments for DQFN

Logic Diagram

Truth Tables

Inputs Outputs

OE

1

LL L

LH H

HX Z

I

n

(Pins 12, 14, 16, 18)

Inputs Outputs

OE

2

LL L

LH H

(Top Through View)

Pin Description

Pin Names Description

OE1, OE

I

0–I7

O

©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX244 Rev. 1.12.1 2

2

0–O7

3-STATE Output Enable Inputs

Inputs

Outputs

HX Z

H = HIGH Voltage Level

L = LOW Voltage Level

X = Immaterial

Z = High Impedance

I

n

(Pins 3, 5, 7, 9)

Absolute Maximum Ratings

Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be
operable above the recommended operating conditions and stressing the parts to these levels is not recommended.
In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability.
The absolute maximum ratings are stress ratings only.

Symbol Parameter Rating

V

CC

V

V

O

I

IK

I

OK

I

O

I

CC

I

GND

T

STG

Note:

3. IO Absolute Maximum Rating must be observed.

Supply Voltage –0.5V to +7.0V

DC Input Voltage –0.5V to +7.0V

I

DC Output Voltage

Output in 3-STATE –0.5V to +7.0V

Output in HIGH or LOW State

(3)

–0.5V to VCC + 0.5V

DC Input Diode Current, VI < GND –50mA

DC Output Diode Current

VO < GND –50mA

> V

V

O

CC

DC Output Source/Sink Current ±50mA

DC Supply Current per Supply Pin ±100mA

DC Ground Current per Ground Pin ±100mA

Storage Temperature –65°C to +150°C

+50mA

74LCX244 — Low Voltage Buffer/Line Driver with 5V Tolerant Inputs and Outputs

Recommended Operating Conditions

(4)

The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended
operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not
recommend exceeding them or designing to absolute maximum ratings.

Symbol Parameter Min. Max. Units

V

CC

V

V

O

I

/ I

OH

T

A

/ ΔV Input Edge Rate, V

Δt

Note:

4. Unused inputs must be held HIGH or LOW. They may not float.

Supply Voltage

Operating 2.0 3.6 V

Data Retention 1.5 3.6

Input Voltage 0 5.5 V

I

Output Voltage

3-STATE 0 5.5 V

HIGH or LOW State 0 V

Output Current

OL

V

= 3.0V–3.6V ±24 mA

CC

= 2.7V–3.0V ±12

V

CC

= 2.3V–2.7V ±8

V

CC

Free-Air Operating Temperature –40 85 °C

= 0.8V–2.0V, VCC = 3.0V 0 10 ns / V

IN

CC

©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX244 Rev. 1.12.1 3

DC Electrical Characteristics

Symbol Parameter V

V

V

V

V

I

I

OFF

I

ΔI

Note:

5. Outputs disabled or 3-STATE only.

HIGH Level Input Voltage 2.3–2.7 1.7 V

IH

LOW Level Input Voltage 2.3–2.7 0.7 V

IL

HIGH Level Output Voltage 2.3–3.6 IOH = –100µA VCC – 0.2 V

OH

LOW Level Output Voltage 2.3–3.6 IOL = 100µA 0.2 V

OL

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

I

I

3-STATE Output Leakage 2.3–3.6 0 ≤ VO ≤ 5.5V,

OZ

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

Quiescent Supply Current 2.3–3.6 VI = VCC or GND 10 µA

CC

Increase in ICC per Input 2.3–3.6 VIH = VCC – 0.6V 500 µA

CC

= –40°C to +85°C

T

A

(V) Conditions

CC

2.7–3.6 2.0

2.7–3.6 0.8

2.3 I

2.7 I

3.0 I

2.3 I

2.7 I

3.0 I

= –8mA 1.8

OH

= –12mA 2.2

OH

= –18mA 2.4

OH

= –24mA 2.2

I

OH

= 8mA 0.6

OL

= 12mA 0.4

OL

= 16mA 0.4

OL

= 24mA 0.55

I

OL

±5.0 µA

VI = VIH or V

3.6V ≤ V

IL

, VO ≤ 5.5V

I

(5)

±10

74LCX244 — Low Voltage Buffer/Line Driver with 5V Tolerant Inputs and Outputs

UnitsMin. Max.

AC Electrical Characteristics

T

= –40°C to +85°C, RL = 500Ω

A

= 3.3V ± 0.3V,

V

CC

C

= 50pF

L

Symbol Parameter

t

PHL

, t

PLH

Propagation Delay,

Min. Max. Min. Max. Min. Max.

1.5 6.5 1.5 7.5 1.5 7.8 ns

Data to Output

t

PZL

t

PLZ

t

OSHL

, t

, t

, t

PZH

PHZ

OSLH

Output Enable Time 1.5 8.0 1.5 9.0 1.5 10.0 ns

Output Disable Time 1.5 7.0 1.5 8.0 1.5 8.4 ns

Output to Output Skew

(6)

1.0 ns

Note:

6. Skew is defined as the absolute value of the difference between the actual propagation delay for any two separate
outputs of the same device. The specification applies to any outputs switching in the same direction, either HIGH-to­LOW (t

©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX244 Rev. 1.12.1 4

) or LOW-to-HIGH (t

OSHL

OSLH

).

V

CC

C

L

= 2.7V,

= 50pF

= 2.5V ± 0.2V,

V

CC

C

= 30pF

L

Units

Dynamic Switching Characteristics

= 25°C

T

A

Symbol Parameter VCC (V) Conditions

V

V

OLP

OLV

Quiet Output Dynamic Peak V

Quiet Output Dynamic Valley V

OL

OL

3.3 CL = 50pF, VIH = 3.3V, VIL = 0V 0.8 V

2.5 C

= 30pF, VIH = 2.5V, VIL = 0V 0.6

L

3.3 CL = 50pF, VIH = 3.3V, VIL = 0V –0.8 V

2.5 C

= 30pF, VIH = 2.5V, VIL = 0V –0.6

L

Capacitance

Symbol Parameter Conditions Typical Units

C

C

OUT

C

PD

Input Capacitance VCC = Open, VI = 0V or V

IN

Output Capacitance VCC = 3.3V, VI = 0V or V

CC

CC

Power Dissipation Capacitance VCC = 3.3V, VI = 0V or VCC, f = 10MHz 25.0 pF

7.0 pF

8.0 pF

74LCX244 — Low Voltage Buffer/Line Driver with 5V Tolerant Inputs and Outputs

UnitTypica l

©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX244 Rev. 1.12.1 5