MAX3218 Datasheet, PDF (1/12 Pages) Maxim Integrated Products – 1uA Supply Current, 1.8V to 4.25V-Powered RS-232 Transceiver with AutoShutdown™

19-0380; Rev 0; 3/95
1µA Supply Current, 1.8V to 4.25V-Powered
RS-232 Transceiver with AutoShutdown™
_______________General Description
The MAX3218 RS-232 transceiver is intended for bat-
tery-powered EIA/TIA-232E and V.28/V.24 communica-
tions interfaces that need two drivers and two receivers
with minimum power consumption from a single low-
voltage supply. It provides a wide +1.8V to +4.25V
operating voltage range while maintaining true RS-232
and EIA/TIA-562 voltage levels. The MAX3218 runs
from two alkaline, NiCd, or NiMH cells without any form
of voltage regulator. A guaranteed 120kbps data rate
provides compatibility with popular software for com-
municating with personal computers.
Supply current is reduced to 1µA with Maxim’s new
AutoShutdown™ feature. When the MAX3218 does not
sense a valid signal level on the receiver inputs, the on-
board power-supply and drivers shut down. This
occurs if the RS-232 cable is disconnected or if the
transmitters of the connected peripheral are turned off.
The system turns on again when a valid level is applied
to either RS-232 receiver input. As a result, the system
saves power without changes to the existing software.
Additionally, the MAX3218 can be forced into or out of
shutdown, under logic control.
While shut down, all receivers can remain active or can
be disabled under logic control, permitting a system
incorporating the CMOS MAX3218 to monitor external
devices while in low-power shutdown. Three-state dri-
vers are provided on both receiver outputs so that multi-
ple receivers, generally of different interface standards,
can be on the same bus. The MAX3218 is available in
20-pin DIP and SSOP packages.
____________________________Features
BETTER THAN BIPOLAR!
o 1µA Supply Current Using AutoShutdown™
o Operates Directly from Two Alkaline,
NiCd or NiMH Cells
o +1.8V to +4.25V Single-Supply Voltage Range
o 120kbps Data Rate Guaranteed
o Low-Cost Surface-Mount Components
o Meets EIA/TIA-232E Specifications
o Three-State Receiver Outputs
o Flow-Through Pinout
o On-Board DC-DC Converters
o 20-Pin SSOP and DIP Packages
______________Ordering Information
PART
MAX3218CPP
MAX3218CAP
MAX3218C/D
MAX3218EPP
MAX3218EAP
TEMP. RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
† Contact factory for dice specifications.
PIN-PACKAGE
20 Plastic DIP
20 SSOP
Dice^†
20 Plastic DIP
20 SSOP
________________________Applications
Battery-Powered Equipment
Subnotebook Computers
PDAs
Hand-Held Equipment
Peripherals
Cellular Phones
* Patent Pending
™ AutoShutdown is a trademark of Maxim Integrated Products.
__________________Pin Configuration
TOP VIEW
LX ₁
INVALID ₂
FORCEON 3
FORCEOFF ₄
GND ₅
V_{CC 6}
T1IN ₇
T2IN ₈
R1OUT ₉
R2OUT ₁₀
MAX3218
20 ^GND
19 V+
18 ^C1+
17 GND
16 C1-
15 V-
14 T1OUT
13 T2OUT
12 R1IN
11 R2IN
DIP/SSOP
________________________________________________________________ Maxim Integrated Products 1
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