The MAX3221/MAX3223/MAX3243 achieve 1µA supply current with Maxim's revolutionary AutoShutdown™ feature. When the MAX3221/MAX3223/MAX3243 do not sense a valid signal level on their 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 any RS-232 receiver input. As a result, the system saves power without changes to the existing BIOS or operating system.
The MAX3221/MAX3223/MAX3243 transceivers are 3V-powered EIA/TIA-232 and V.28/V.24 communications interfaces intended for notebook computer applications. A proprietary, high-efficiency, dual charge-pump power supply and a low-dropout transmitter combine to deliver true RS-232 performance from a single +3.0V to +5.5V supply. A guaranteed data rate of 120kbps provides compatibility with popular software for communicating with personal computers.
The MAX3221/MAX3223/MAX3243 require only 0.1µF capacitors in 3.3V operation, and can operate from input voltages ranging from +3.0V to +5.5V. They are ideal for 3.3V-only systems, mixed 3.3V and 5.0V systems, or 5.0V-only systems that require true RS-232 performance.
The MAX3221 is a 1-driver/1-receiver 16-pin SSOP version of the 20-pin MAX3223 (2-driver/2-receiver). The MAX3243 3-driver/5-receiver, complete serial port is ideal for notebook or subnotebook computers. The MAX3243 includes one complementary always-active receiver. This receiver can monitor an external device (such as a modem) in shutdown, without forward biasing the protection diodes in a UART that may have VCC completely removed.
Key Features
Applications/Uses
For Space-Constrained Applications:
MAX3228/MAX3229: +2.5V to +5.5V RS-232 Transceivers in UCSP
For Integrated ESD Protection:
MAX3222E/MAX3232E/MAX3237E/MAX3241E*/
MAX3246E: ±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V, Up to 1Mbps, True RS-232 Transceivers (MAX3246E Available in UCSP Package)
For Low-Voltage or Data Cable Applications:
MAX3380E/MAX3381E: +2.5V to +5.5V, 1µA,
2 Tx/2 Rx RS-232 Transceivers with ±15kV ESD-Protected I/O and Logic Pins
Notes: *This pricing is BUDGETARY, for comparing similar parts. Prices are in
U.S. dollars and subject to change. Quantity pricing may vary
substantially and international prices may differ due to local
duties, taxes, fees, and exchange rates. For volume-specific prices
and delivery, please see the price and availability page
or contact an authorized distributor.
Auto shutdown reduces supply current to 1µA (MAX3221)
Auto shutdown reduces supply current to 1µA (MAX3223)
Auto shutdown reduces supply current to 1µA, complementary receiver, drives mice (MAX3243)
* 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;
and other patents pending.