19-1289; Rev 1; 3/98
1µA Supply Current, 1Mbps, 3.0V to 5.5V,
RS-232 Transceivers with AutoShutdown Plus
________________General Description
The MAX3224–MAX3227/MAX3244/MAX3245 are 3V-
powered EIA/TIA-232 and V.28/V.24 communications
interfaces with automatic shutdown/wakeup features
and high data-rate capabilities.
All devices achieve a 1µA supply current using Maxim’s
revolutionary AutoShutdown Plus™ feature. These
devices automatically enter a low-power shutdown
mode when the RS-232 cable is disconnected or the
transmitters of the connected peripherals are inactive,
and the UART driving the transmitter inputs is inactive
for more than 30 seconds. They turn on again when
they sense a valid transition at any transmitter or receiv-
er input. AutoShutdown Plus saves power without
changes to the existing BIOS or operating system.
The MAX3225/MAX3227/MAX3245 also feature
MegaBaud™ operation, guaranteeing 1Mbps for high-
speed applications such as communicating with ISDN
modems. The MAX3224/MAX3226/MAX3244 guarantee
250kbps operation. The transceivers have a proprietary
low-dropout transmitter output stage enabling true RS-
232 performance from a +3.0V to +5.5V supply with a
dual charge pump. The charge pump requires only four
small 0.1µF capacitors for operation from a 3.3V supply.
The MAX3224–MAX3227 feature a logic-level output
(READY) that asserts when the charge pump is regulat-
ing and the device is ready to begin transmitting.
All devices are available in a space-saving SSOP pack-
age.
____________________________Features
o
1µA Supply Current
o
AutoShutdown Plus—EDN Innovation of the Year
o
Guaranteed Data Rate:
250kbps (MAX3224/3226/3244)
1Mbps (MAX3225/3227/3245)
o
Guaranteed Slew Rate:
6V/µs (MAX3224/3226/3244)
24V/µs (MAX3225/3227/3245)
o
Meets EIA/TIA-232 Specifications Down to 3.0V
o
Guaranteed Mouse Driveability (MAX3244/3245)
o
Ready-to-Transmit Logic-Level Output
MAX3224–MAX3227/MAX3244/MAX3245
†
_______________Ordering Information
PART
MAX3224CPP
MAX3224CAP
MAX3224EPP
MAX3224EAP
MAX3225CPP
MAX3225CAP
MAX3225EPP
MAX3225EAP
TEMP. RANGE
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
20 Plastic DIP
20 SSOP
20 Plastic DIP
20 SSOP
20 Plastic DIP
20 SSOP
20 Plastic DIP
20 SSOP
________________________Applications
Notebook, Subnotebook, and Palmtop Computers
Cellular Phones
Battery-Powered Equipment
Hand-Held Equipment
Peripherals
Printers
Ordering Information continued at end of data sheet.
_____________________ Selector Guide
PART
NO. OF
GUARANTEED
AUTO-
READY
DRIVERS/
DATA RATE
SHUTDOWN
OUTPUT
RECEIVERS
(bps)
PLUS
2/2
2/2
1/1
1/1
3/5
3/5
250k
1M
250k
1M
250k
1M
—
—
MAX3224
MAX3225
MAX3226
MAX3227
MAX3244
MAX3245
AutoShutdownPlus and MegaBaud are trademarks of Maxim Integrated Products.
†
Covered by U.S. Patent numbers 4,636,930; 4,679,134; 4,777,577; 4,797,899; 4,809,152; 4,897,774; 4,999,761; 5,649,210; and other patents pending.
________________________________________________________________
Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 408-737-7600 ext. 3468.
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
