19-0246; Rev 1; 7/95
1.8V to 4.25V-Powered,
True RS-232 Dual Transceiver
_______________General Description
The MAX218 RS-232 transceiver is intended for battery-
powered EIA/TIA-232E and V.28/V.24 communications
interfaces that need two drivers and two receivers with
minimum power consumption. It provides a wide +1.8V
to +4.25V operating voltage range while maintaining
true RS-232 and EIA/TIA-562 voltage levels. The
MAX218 runs from two alkaline, NiCd, or NiMH cells
without any form of voltage regulator.
A shutdown mode reduces current consumption to
1碌A, extending battery life in portable systems. While
shut down, all receivers can remain active or can be
disabled under logic control, permitting a system incor-
porating the CMOS MAX218 to monitor external
devices while in low-power shutdown mode.
A guaranteed 120kbps data rate provides compatibility
with popular software for communicating with personal
computers. Three-state drivers are provided on all
receiver outputs so that multiple receivers, generally of
different interface standards, can be wire-ORed at the
UART. The MAX218 is available in 20-pin DIP, SO, and
SSOP packages.
____________________________Features
BETTER THAN BIPOLAR!
o
Operates Directly from Two Alkaline, NiCd,
or NiMH Cells
o
+1.8V to +4.25V Supply Voltage Range
o
120kbps Data Rate
o
Low-Cost Surface-Mount Components
o
Meets EIA/TIA-232E Specifications
o
1碌A Low-Power Shutdown Mode
o
Both Receivers Active During Low-Power Shutdown
o
Three-State Receiver Outputs
o
Flow-Through Pinout
o
On-Board DC-DC Converters
o
20-Pin SSOP, Wide SO, or DIP Packages
MAX218
______________Ordering Information
PART
MAX218CPP
MAX218CWP
MAX218CAP
MAX218C/D
MAX218EPP
MAX218EWP
MAX218EAP
TEMP. RANGE
0掳C to +70掳C
0掳C to +70掳C
0掳C to +70掳C
0掳C to +70掳C
-40掳C to +85掳C
-40掳C to +85掳C
-40掳C to +85掳C
PIN-PACKAGE
20 Plastic DIP
20 Wide SO
20 SSOP
Dice*
20 Plastic DIP
20 Wide SO
20 SSOP
________________________Applications
Battery-Powered Equipment
Computers
Printers
Peripherals
Instruments
Modems
*Contact factory for dice specifications.
__________Typical Operating Circuit
1
LX
V
CC
19
V+
V-
__________________Pin Configuration
TOP VIEW
LX 1
20 GND
19 V+
18 C1+
17 GND
1.8V
TO
4.25V
6
15
N.C. 2
SHDN 3
EN 4
GND 5
V
CC
6
ON/OFF
3
MAX218
SHDN
T1
T2
R1
R2
4
C1+ 18
C1-
16
7 T1IN
8 T2IN
9 R1OUT
10 R2OUT
EN
ENABLE
T1OUT 14
T2OUT 13
R1IN 12
R2IN 11
GND
5, 17, 20
MAX218
16 C1-
15 V-
14 T1OUT
13 T2OUT
12 R1IN
11 R2IN
T1IN 7
T2IN 8
R1OUT 9
R2OUT 10
DIP/SO/SSOP
1
________________________________________________________________
Maxim Integrated Products
Call toll free 1-800-998-8800 for free samples or literature.
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