MULTICHANNAEL RS-232 LINE DRIVERS/RECEIVERS

DESCRIPTION

The UTC UT3243A consists of 3 drivers and 5 receivers. It meets
ElA/TIA-232 and V.28/V.24 specifications, it intended for notebook
computer applications. A high-efficiency, dual charge-pumps power
supply and a low-dropout transmitter combine to deliver true RS-232
performance from a single +3.0V ~ +5.5V power supply. A
guaranteed data rate of 120kbps provides compatibility with popular
software for communicating with PCs.

The UTC UT3243A achieves 1µA supply current in shutdown condition. When the UT3243A doesn’t detect a
valid signal level on its receiver inputs, the on-board power supply and drivers will shutdown, and when a valid level
is applied to any RS-232 receiver input, then the system turns on again. Therefore, the system saves power without
changes to the existing BIOS or operating system.
The UTC UT3243A requires only 0.1µF capacitors in 3.3V operation, and can operate from input voltages ranging
from +3.0V ~ +5.5V. It is ideal for 3.3V-only systems, 5.0V-only systems, or mixed 3.3V and 5.0V systems that
require true RS-232 performance.
The UTC UT3243A includes one complementary always-active receiver that 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.

FEATURES

* Operates With 3.0V ~ 5.5V Power Supply
* Three Drivers and Five Receivers
* Operates Up To 235 kbps
* Designed to Transmit at a Data Rate of 235 kbps
* Low Standby Current (1uA Typical)
* External Capacitors (4×0.1µF)
* Accepts 5.0V Logic Input With 3.3V Supply
* Always-Active Non-inverting Receiver Output (R2OUTB)
* Serial-Mouse Drivability
* ESD(HBM) Protected ±8KV(MIN.) for RS-232 Pins