74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0
February 2008
74LCX245
Low Voltage Bidirectional Transceiver with 5V Tolerant
Inputs and Outputs
Features
■
5V tolerant inputs and outputs
■
2.3V to 3.6V V
CC
specifications provided
■
7.0ns t
PD
max. (V
CC
=
3.3V), 10µA I
CC
max.
■
Power down high impedance inputs and outputs
■
Supports live insertion/withdrawal
(1)
■
±24mA output drive (V
CC
=
3.0V)
■
■
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 V
CC
through a pull-up
resistor: the minimum value or the resistor is
determined by the current-sourcing capability of the
driver.
General Description
The LCX245 contains eight non-inverting bidirectional
buffers with 3-STATE outputs and is intended for bus
oriented applications. The device is designed 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 high impedance state.
The LCX245 is fabricated with an advanced CMOS tech-
nology to achieve high speed operation while maintain-
ing CMOS low power dissipation.
Ordering Information
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.
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, 5.3mm Wide
74LCX245BQX
(2)
MLP20B 20-Terminal Depopulated Quad Very-Thin Flat Pack No Leads (DQFN),
JEDEC MO-241, 2.5 x 4.5mm
74LCX245MSA MSA20 20-Lead Shrink Small Outline Package (SSOP), JEDEC MO-150, 5.3mm Wide
74LCX245MTC MTC20 20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153,
4.4mm Wide
Implements proprietary noise/EMI reduction circuitry
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 2
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Connection Diagrams
Pin Assignments for SOIC, SOP, SSOP, and TSSOP
Pin Assignment for DQFN
(Top Through View)
Pin Description
Logic Symbol
Truth Table
H
=
HIGH Voltage Level
L
=
LOW Voltage Level
X
=
Immaterial
Z
=
High Impedance
Note:
3. Unused bus terminals during HIGH Z State must be
held HIGH or LOW.
Logic Diagram
Pin
Names
Description
OE Output Enable Input
T/R Transmit/Receive Input
A
0
–A
7
Side A Inputs or 3-STATE Outputs
B
0
–B
7
Side B Inputs or 3-STATE Outputs
Inputs
OutputsOE T/R
LLBus B
0
– B
7
Data to Bus A
0
– A
7
LHBus A
0
– A
7
Data to Bus B
0
– B
7
HXHIGH Z State on A
0
– A
7
, B
0
– B
7(3)
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 3
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
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.
Note:
4. I
O
Absolute Maximum Rating must be observed.
Recommended Operating Conditions
(5)
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.
Note:
5. Unused inputs must be held HIGH or LOW. They may not float.
Symbol Parameter Rating
V
CC
Supply Voltage –0.5V to +7.0V
V
I
DC Input Voltage –0.5V to +7.0V
V
O
DC Output Voltage
Output in 3-STATE –0.5V to +7.0V
Output in HIGH or LOW State
(4)
–0.5V to V
CC
+ 0.5V
I
IK
DC Input Diode Current, V
I
<
GND –50mA
I
OK
DC Output Diode Current
V
O
<
GND –50mA
V
O
>
V
CC
+50mA
I
O
DC Output Source/Sink Current ±50mA
I
CC
DC Supply Current per Supply Pin ±100mA
I
GND
DC Ground Current per Ground Pin ±100mA
T
STG
Storage Temperature –65°C 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 0 5.5 V
V
O
Output Voltage
3-STATE 0 5.5 V
HIGH or LOW State 0 V
CC
I
OH
/
I
OL
Output Current
V
CC
=
3.0V–3.6V ±24 mA
V
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, V
CC
=
3.0V 0 10 ns
/
V
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 4
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
DC Electrical Characteristics
Note:
6. Outputs disabled or 3-STATE only.
AC Electrical Characteristics
Note:
7. 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-to-LOW (t
OSHL
) or LOW-to-HIGH (t
OSLH
).
Symbol Parameter V
CC
(V) Conditions
T
A
=
–40°C to +85°C
UnitsMin. 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 2.3–3.6 I
OH
=
–100µA V
CC
– 0.2 V
2.3 I
OH
=
–8mA 1.8
2.7 I
OH
=
–12mA 2.2
3.0 I
OH
=
–18mA 2.4
I
OH
=
–24mA 2.2
V
OL
LOW Level Output Voltage 2.3–3.6 I
OL = 100µA 0.2 V
2.3 IOL = 8mA 0.6
2.7 IOL = 12mA 0.4
3.0 IOL = 16mA 0.4
IOL = 24mA 0.55
IIInput Leakage Current 2.3–3.6 0 ≤ VI ≤ 5.5V ±5.0 µA
IOZ 3-STATE Output Leakage 2.3–3.6 0 ≤ VO ≤ 5.5V,
VI = VIH or VIL
±5.0 µA
IOFF Power-Off Leakage Current 0 VI or VO = 5.5V 10 µA
ICC Quiescent Supply Current 2.3–3.6 VI = VCC or GND 10 µA
3.6V ≤ VI, VO ≤ 5.5V(6) ±10
∆ICC Increase in ICC per Input 2.3–3.6 VIH = VCC – 0.6V 500 µA
Symbol Parameter
TA = –40°C to +85°C, RL = 500Ω
Units
VCC = 3.3V ± 0.3V,
CL = 50pF
VCC = 2.7V,
CL = 50pF
VCC = 2.5V ± 0.2V,
CL = 30pF
Min. Max. Min. Max. Min. Max.
tPHL, tPLH Propagation Delay,
An to Bn or Bn to An
1.5 7.0 1.5 8.0 1.5 8.4 ns
tPZL, tPZH Output Enable Time 1.5 8.5 1.5 9.5 1.5 10.5 ns
tPLZ, tPHZ Output Disable Time 1.5 7.5 1.5 8.5 1.5 9.0 ns
tOSHL, tOSLH Output to Output Skew(7) 1.0 ns
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 5
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Dynamic Switching Characteristics
Capacitance
Symbol Parameter VCC (V) Conditions
TA = 25°C
UnitTypical
VOLP Quiet Output Dynamic Peak VOL 3.3 CL = 50pF, VIH = 3.3V, VIL = 0V 0.8 V
2.5 CL = 30pF, VIH = 2.5V, VIL = 0V 0.6
VOLV Quiet Output Dynamic Valley VOL 3.3 CL = 50pF, VIH = 3.3V, VIL = 0V –0.8 V
2.5 CL = 30pF, VIH = 2.5V, VIL = 0V –0.6
Symbol Parameter Conditions Typical Units
CIN Input Capacitance VCC = Open, VI = 0V or VCC 7.0 pF
COUT Output Capacitance VCC = 3.3V, VI = 0V or VCC 8.0 pF
CPD Power Dissipation Capacitance VCC = 3.3V, VI = 0V or VCC, f = 10MHz 25.0 pF
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 6
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
AC Loading and Waveforms (Generic for LCX Family)
Figure 1. AC Test Circuit (CL includes probe and jig capacitance)
Waveform for Inverting and Non-Inverting Functions
Propagation Delay. Pulse Width and trec Waveforms
3-STATE Output Low Enable and
Disable Times for Logic
3-STATE Output High Enable and
Disable Times for Logic
Setup Time, Hold Time and Recovery Time for Logic
trise and tfall
Figure 2. Waveforms (Input Characteristics; f = 1MHz, tr = tf = 3ns)
Test Switch
tPLH, tPHL Open
tPZL, tPLZ 6V at VCC = 3.3 ± 0.3V
VCC x 2 at VCC = 2.5 ± 0.2V
tPZH, tPHZ GND
Symbol
VCC
3.3V ± 0.3V 2.7V 2.5V ± 0.2V
Vmi 1.5V 1.5V VCC / 2
Vmo 1.5V 1.5V VCC / 2
VxVOL + 0.3V VOL + 0.3V VOL + 0.15V
VyVOH – 0.3V VOH – 0.3V VOH – 0.15V
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 7
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Schematic Diagram (Generic for LCX Family)
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 8
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Tape and Reel Specification
Tape Format for DQFN
Tape Dimension inches (millimeters)
Reel Dimensions inches (millimeters)
Package Designator Tape Section Number of Cavities Cavity Status Cover Tape Status
BQX Leader (Start End) 125 (typ.) Empty Sealed
Carrier 3000 Filled Sealed
Trailer (Hub End) 75 (typ.) Empty Sealed
Tape Size A B C D N W1 W2
12mm 13.0 (330.0) 0.059 (1.50) 0.512 (13.00) 0.795 (20.20) 2.165 (55.00) 0.488 (12.4) 0.724 (18.4)
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 9
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Physical Dimensions
Figure 3. 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300" Wide
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or
obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions,
specifically the warranty therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/
0.10 C
C
A
SEE DETAIL A
NOTES: UNLESS OTHERWISE SPECIFIED
A) THIS PACKAGE CONFORMS TO JEDEC
MS-013, VARIATION AC, ISSUE E
B) ALL DIMENSIONS ARE IN MILLIMETERS.
C) DIMENSIONS DO NOT INCLUDE MOLD
FLASH OR BURRS.
E) LANDPATTERN STANDARD: SOIC127P1030X265-20L
PIN ONE
INDICATOR
0.25
110
BC A
M
20 11
B
X 45°
8°
0°
SEATING PLANE
GAGE PLANE
DETAIL A
SCALE: 2:1
SEATING PLANE
LAND PATTERN RECOMMENDATION
F) DRAWING FILENAME: MKT-M20BREV3
0.65
1.27
2.25
9.50
13.00
12.60
11.43
7.60
7.40
10.65
10.00
0.51
0.35 1.27
2.65 MAX
0.30
0.10
0.33
0.20
0.75
0.25
(R0.10)
(R0.10)
1.27
0.40
(1.40)
0.25
D) CONFORMS TO ASME Y14.5M-1994
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 10
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Physical Dimensions (Continued)
Figure 4. 20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or
obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions,
specifically the warranty therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 11
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Physical Dimensions (Continued)
Figure 5. 20-Terminal Depopulated Quad Very-Thin Flat Pack No Leads (DQFN), JEDEC MO-241, 2.5 x 4.5mm
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or
obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions,
specifically the warranty therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 12
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Physical Dimensions (Continued)
Figure 6. 20-Lead Shrink Small Outline Package (SSOP), JEDEC MO-150, 5.3mm Wide
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or
obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions,
specifically the warranty therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 13
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Physical Dimensions (Continued)
Figure 8. 20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or
obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions,
specifically the warranty therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/
©1994 Fairchild Semiconductor Corporation www.fairchildsemi.com
74LCX245 Rev. 1.11.0 14
TRADEMARKS
Thefollowing includes registered and unregistered trademarks and service marks, owned by Fairchild Semiconductor and/or its global
subsidiaries, and is not intended to be an exhaustive list of all such trademarks.
ACEx®
Build it Now™
CorePLUS™
CROSSVOLT™
CTL™
Current Transfer Logic™
EcoSPARK®
EZSWITCH™ *
™
®
Fairchild®
Fairchild Semiconductor®
FACT Quiet Series™
FACT®
FAST®
FastvCore™
FlashWriter®*
FPS™
FRFET®
Global Power ResourceSM
Green FPS™
Green FPS™e-Series™
GTO™
i-Lo™
IntelliMAX™
ISOPLANAR™
MegaBuck™
MICROCOUPLER™
MicroFET™
MicroPak™
MillerDrive™
Motion-SPM™
OPTOLOGIC®
OPTOPLANAR®
®
PDP-SPM™
Power220®
POWEREDGE®
Power-SPM™
PowerTrench®
Programmable Active Droop™
QFET®
QS™
QT Optoelectronics™
Quiet Series™
RapidConfigure™
SMART START™
SPM®
STEALTH™
SuperFET™
SuperSOT™-3
SuperSOT™-6
SuperSOT™-8
SupreMOS™
SyncFET™®
The Power Franchise®
TinyBoost™
TinyBuck™
TinyLogic®
TINYOPTO™
TinyPower™
TinyPWM™
TinyWire™
µSerDes™
UHC®
Ultra FRFET™
UniFET™
VCX™
*EZSWITCH™ and FlashWriter®are trademarks of System General Corporation, used under license by Fairchild Semiconductor.
DISCLAIMER
FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS
HEREIN TO IMPROVE RELIABILITY, FUNCTION, OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE
APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS
PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. THESE SPECIFICATIONS DO NOT EXPAND THE TERMS OF FAIRCHILD’S
WORLDWIDE TERMS AND CONDITIONS, SPECIFICALLY THE WARRANTY THEREIN, WHICH COVERS THESE PRODUCTS.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR
SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF FAIRCHILD SEMICONDUCTOR CORPORATION.
As used herein:
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the body or
(b) support or sustain life, and (c) whose failure to perform
when properly used in accordance with instructions for use
provided in the labeling, can be reasonably expected to
result in a significant injury of the user.
2. A critical component in any component of a life support,
device, or system whose failure to perform can be
reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
PRODUCT STATUS DEFINITIONS
Definition of Terms
Datasheet Identification Product Status Definition
Advance Information Formative or In Design This datasheet contains the design specifications for product
development. Specifications may change in any manner without notice.
Preliminary First Production
This datasheet contains preliminary data; supplementary data will be
published at a later date. Fairchild Semiconductor reserves the right to
make changes at any time without notice to improve design.
No Identification Needed Full Production
This datasheet contains final specifications. Fairchild Semiconductor
reserves the right to make changes at any time without notice to improve
the design.
Obsolete Not In Production
This datasheet contains specifications on a product that has been
discontinued by Fairchild Semiconductor. The datasheet is printed for
reference information only.
Rev. I33
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
