• Wide supply voltage range:
3 V port: 1.5 to 3.6 V
5 V port: 1.5 to 5.5 V
DESCRIPTION
The 74LVC4245A is a high-performance, low-power, low-voltage, Si-gate
CMOS device, superior to most advanced CMOS compatible TTL families.
The 74LVC4245A is an octal dual supply translating transceiver featuring
non-inverting 3-state bus compatible outputs in both send and receive
directions. It is designed to interface between a 3 and 5 V bus in a mixed 3/5 V
supply environment.
• CMOS low power consumption
• Direct interface with TTL levels
• Control inputs accept voltages up
The 74LVC4245A features an output enable (OE) input for easy cascading and
a send/receive (DIR) input for direction control. (OE) controls the outputs so
that the buses are effectively isolated.
to 5.5 V.
In suspend mode, when V
is zero, there will be no current flow from one
CCA
supply to the other supply. The A-outputs must be set 3-state and the voltage
on the A-bus must be smaller than V
(typ. 0.7 V). V
diode
CCA
≥ V
CCB
suspend mode).
QUICK REFERENCE DATA
GND = 0 V; T
=25°C; tr=tf≤2.5 ns.
amb
SYMBOLPARAMETERCONDITIONSTYPICALUNIT
t
PHL/tPLH
C
I/O
C
PDA
C
PDB
propagation delayCL=50pF
A
to B
n
n
B
to A
n
n
V
= 5.0 V4.0ns
CCA
V
= 3.3 V4.0ns
CCB
input/output capacitance10.0pF
A port
to B
A
n
n
B
to A
n
n
VI= GND to VCC; note 17.8pF
VI= GND to VCC; note 127.9pF
B port
to B
A
n
n
B
to A
n
n
VI= GND to VCC; note 126pF
VI= GND to VCC; note 110.4pF
(except in
Note
1. C
is used to determine the dynamic power dissipation (PDin µW).
PD
PD=CPD× V
2
× fi+ Σ(CL× V
CC
2
× fo) where:
CC
fi= input frequency in MHz;
fo= output frequency in MHz;
CL= output load capacitance in pF;
VCC= supply voltage in Volts;
Σ(CL× V
DC input voltage range (control inputs)05.5V
DC input voltage range; output 3-state05.5V
DC output voltage range; output HIGH or
0V
CC
V
LOW state
T
amb
operating ambient temperature rangesee DC and AC characteristics
−40+85°C
per device
t
r,tf
input rise and fall timesV
= 2.7 to 3.0 V020ns/V
CCB
V
= 3.0 to 3.6 V010
CCB
V
= 3.0 to 4.5 V020
CCA
= 4.5 to 5.5 V010
V
CCA
LIMITING VALUES
In accordance with the Absolute Maximum Rating System (IEC 134). Voltages are referenced to GND (ground = 0 V).
SYMBOLPARAMETERCONDITIONSMIN.MAX.UNIT
V
V
I
V
I
V
CCA
CCB
IK
I
OK
I/O
DC supply voltage 5 V port−0.5+6.5V
DC supply voltage 3 V port−0.5+4.6V
DC input diode currentVI<0−−50mA
DC input voltagenote 1−0.5+6.5V
DC output diode currentVO>VCC or VO<0−±50mA
DC output voltage; output HIGH or LOW note 1−0.5VCC+ 0.5V
DC input voltage; output 3-statenote 1−0.5+6.5V
I
O
I
GND
T
P
, I
stg
tot
DC output diode currentVO=0toV
DC VCC or GND current−±100mA
CC
CC
−±50mA
storage temperature−65+150°C
power dissipation per package
plastic mini-pack (SO)above 70 °C derate linearly
−500mW
with 8 mW/K
plastic shrink mini-pack (SSOP and
TSSOP)
above 60 °C derate linearly
with 5.5 mW/K
−500mW
Note
1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed.
SOLDERING
Introduction to soldering surface mount packages
This text gives a very brief insight to a complex technology.
A more in-depth account of soldering ICs can be found in
our
“Data Handbook IC26; Integrated Circuit Packages”
(document order number 9398 652 90011).
There is no soldering method that is ideal for all surface
mount IC packages. Wave soldering is not always suitable
for surface mount ICs, or for printed-circuit boards with
high population densities. In these situations reflow
soldering is often used.
Reflow soldering
Reflow soldering requires solder paste (a suspension of
fine solder particles, flux and binding agent) to be applied
to the printed-circuit board by screen printing, stencilling or
pressure-syringe dispensing before package placement.
Several methods exist for reflowing; for example,
infrared/convection heating in a conveyor type oven.
Throughput times (preheating, soldering and cooling) vary
between 100 and 200 seconds depending on heating
method.
Typical reflow peak temperatures range from
215 to 250 °C. The top-surface temperature of the
packages should preferable be kept below 230 °C.
• Use a double-wave soldering method comprising a
turbulent wave with high upward pressure followed by a
smooth laminar wave.
• For packages with leads on two sides and a pitch (e):
– larger than or equal to 1.27 mm, the footprint
longitudinal axis is preferred to be parallel to the
transport direction of the printed-circuit board;
– smaller than 1.27 mm, the footprint longitudinal axis
must be parallel to the transport direction of the
printed-circuit board.
The footprint must incorporate solder thieves at the
downstream end.
• For packages with leads on four sides, the footprint must
be placed at a 45° angle to the transport direction of the
printed-circuit board. The footprint must incorporate
solder thieves downstream and at the side corners.
During placement and before soldering, the package must
be fixed with a droplet of adhesive. The adhesive can be
applied by screen printing, pin transfer or syringe
dispensing. The package can be soldered after the
adhesive is cured.
Typical dwell time is 4 seconds at 250 °C.
A mildly-activated flux will eliminate the need for removal
of corrosive residues in most applications.
Manual soldering
Wave soldering
Conventional single wave soldering is not recommended
for surface mount devices (SMDs) or printed-circuit boards
with a high component density, as solder bridging and
non-wetting can present major problems.
To overcome these problems the double-wave soldering
method was specifically developed.
If wave soldering is used the following conditions must be
observed for optimal results:
Fix the component by first soldering two
diagonally-opposite end leads. Use a low voltage (24 V or
less) soldering iron applied to the flat part of the lead.
Contact time must be limited to 10 seconds at up to
300 °C.
When using a dedicated tool, all other leads can be
soldered in one operation within 2 to 5 seconds between
270 and 320 °C.
1. All surface mount (SMD) packages are moisture sensitive. Depending upon the moisture content, the maximum
temperature (with respect to time) and body size of the package, there is a risk that internal or external package
cracks may occur due to vaporization of the moisture in them (the so called popcorn effect). For details, refer to the
Drypack information in the
2. These packages are not suitable for wave soldering as a solder joint between the printed-circuit board and heatsink
(at bottom version) can not be achieved, and as solder may stick to the heatsink (on top version).
3. If wave soldering is considered, then the package must be placed at a 45° angle to the solder wave direction.
The package footprint must incorporate solder thieves downstream and at the side corners.
4. Wave soldering is only suitable for LQFP, TQFP and QFP packages with a pitch (e) equal to or larger than 0.8 mm;
it is definitely not suitable for packages with a pitch (e) equal to or smaller than 0.65 mm.
5. Wave soldering is only suitable for SSOP and TSSOP packages with a pitch (e) equal to or larger than 0.65 mm; it is
definitely not suitable for packages with a pitch (e) equal to or smaller than 0.5 mm.
DEFINITIONS
Data sheet status
Objective specificationThis data sheet contains target or goal specifications for product development.
Preliminary specificationThis data sheet contains preliminary data; supplementary data may be published later.
Product specificationThis data sheet contains final product specifications.
Limiting values
Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one or
more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation
of the device at these or at any other conditions above those given in the Characteristics sections of the specification
is not implied. Exposure to limiting values for extended periods may affect device reliability.
Application information
Where application information is given, it is advisory and does not form part of the specification.
LIFE SUPPORT APPLICATIONS
These products are not designed for use in life support appliances, devices, or systems where malfunction of these
products can reasonably be expected to result in personal injury. Philips customers using or selling these products for
use in such applications do so at their own risk and agree to fully indemnify Philips for any damages resulting from such
improper use or sale.
United States: 811 East Arques Avenue, SUNNYVALE, CA 94088-3409,
Tel. +1 800 234 7381, Fax. +1 800 943 0087
Uruguay: see South America
Vietnam: see Singapore
Yugoslavia: PHILIPS, Trg N. Pasica 5/v, 11000 BEOGRAD,
Tel. +381 11 62 5344, Fax.+381 11 63 5777
For all other countries apply to: Philips Semiconductors,
International Marketing & Sales Communications, Building BE-p, P.O. Box 218,
5600 MD EINDHOVEN, The Netherlands, Fax. +31 40 27 24825
The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed
without notice. No liability will be accepted by the publisher for any consequence of its use. Publication thereof does not convey nor imply any license
under patent- or other industrial or intellectual property rights.
199966
Internet: http://www.semiconductors.philips.com
Printed in The Netherlands245004/03/pp16 Date of release: 1999Jun 15Document order number: 9397 750 06037
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