UCC283-ADJ

V_IN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  . 9V
CT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  -0.3 to 3V
ADJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.3 to 9V
Storage Temperature . . . . . . . . . .  -65°C to +150°C
Junction Temperature. . . . . . . . . . . -55°C to +150°C
Lead Temperature (Soldering, 10 sec.) . . . . . +300°C

Currents are positive into, negative out of the specified terminal.Consult Packaging Section of Databook for thermal limitations and considerations of packages. All voltages are referenced to GND.

The UCC283-3/-5/-ADJ family of positive linear series pass regulators are tailored for low drop out applications where low quiescent power is important. Fabricated with a BiCMOS technology ideally suited for low input to output differential applications,the UCC283-5 will pass 3A while requiring only 0.45V of typical input voltage headroom (guaranteed 0.6V dropout). These regulators include reverse voltage sensing that prevents current in the reverse direction. Quiescent current is always less than 650mA. These devices have been internally compensated in such a manner that the need for a minimum output capacitor has been eliminated.

UCC283-3 and UCC283-5 versions are in 3 lead packages and have preset outputs at 3.3V and 5.0V respectively. The output voltage is regulated to 1.5% at room temperature.The UCC283-ADJ version, in a 5 lead package, regulates the output voltage programmed by an external resistor ratio.

UCC283-3 and UCC283-5 Short circuit current is internally limited. The device responds to a sustained overcurrent condition by turning off after a T_ON delay. The device then stays off for a period,TOFF, that is 32 times the T_ON delay. The device then begins pulsing on and off at the T_ON/(T_ON+T_OFF) duty cycle of 3%. This drastically reduces the power dissipation during short circuit and means heat sinks need only accommodate normal operation.On the 3 leaded versions of the device T_ON is fixed at 750ms, on the adjustable 5 leaded versions an external capacitor sets the on time - the off time is always 32 times TON. The external timing control pin, CT, on the five leaded versions also serves as a shutdown input when pulled low.

UCC283-3 and UCC283-5 Internal power dissipation is further controlled with thermal overload protection circuitry.Thermal shutdown occurs if the junction temperature exceeds 165°C. The chip will remain off until the temperature has dropped 20°C.

The UCC283 series is specified for operation over the industrial range of -40°C to +85°C, and the UCC383 series is specified from 0°C to +70°C. These devices are available in 3 and 5 pin TO-220 and TO-263 power packages.