AD7306 Datasheet, PDF (1/8 Pages) Analog Devices – +5 V Powered RS-232/RS-422 Transceiver

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+5 V Powered
RS-232/RS-422 Transceiver
FEATURES
RS-232 and RS-422 on One Chip
Single +5 V Supply
0.1 ␮F Capacitors
Short Circuit Protection
Excellent Noise Immunity
Low Power BiCMOS Technology
High Speed, Low Skew RS-422 Operation
–40؇C to +85؇C Operations
APPLICATIONS
DTE-DCE Interface
Packet Switching
Local Area Networks
Data Concentration
Data Multiplexers
Integrated Services Digital Network (ISDN)
GENERAL DESCRIPTION
The AD7306 line driver/receiver is a 5 V monolithic product
which provides an interface between TTL signal levels and dual
standard EIA RS-232/RS-422 signal levels. The part contains
two RS-232 drivers, one RS-422 driver, one RS-232 receiver,
and one receiver path which can be configured either as RS-232
or as RS-422.
An internal charge pump voltage converter facilitates operation
from a single +5 V power supply. The internal charge pump
generates ± 10 V levels allowing RS-232 output levels to be de-
veloped without the need for external bipolar power supplies.
A highly efficient charge pump design allows operation using
non polarized, miniature 0.1 µF capacitors. This gives a consid-
erable saving in printed circuit board space over conventional
products which can use up to 10 µF capacitors. The charge
pump output voltages may also be used to power external cir-
cuitry which requires dual supplies.
AD7306
FUNCTIONAL BLOCK DIAGRAM
V+ 1
C1+ ²
C1– ³
R2_IN 4
T1_OUT 5
T2_OUT 6
V_CC 7
R1_IN (B) 8
R1_IN /R1_IN (A) ₉
T3_OUT (B) ₁₀
T3_OUT (A) 11
NC ¹²
AD7306
SOIC
TOP VIEW
(Not to Scale)
24 _V–
23 C2–
22 C2+
21 R2_OUT
20 T1_IN
19 T2_IN
18 _GND
17 R1_OUT
16 ^T3_IN
15 232/422 SEL
14 _GND
13 NC
NC = NO CONNECT
The RS-232 channels are suitable for communications rates up
to 100 kHz and the RS-422 channels are suitable for high speed
communications up to 5 MHz. The RS-422 transmitter comple-
mentary outputs are closely matched and feature low timing
skew between the complementary outputs. This is often an es-
sential requirement to meet tight system timing specifications.
All inputs feature ESD protection, all driver outputs feature
high source and sink current capability and are internally pro-
tected against short circuits on the outputs. An epitaxial layer is
used to guard against latch-up.
The part is available in a 24-lead SOIC and 24-pin plastic DIP
package.
REV. B
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use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
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