EXCLUSIVE FORUM FOR MACHINE DISMANTLERS AND REPAIR PEOPLE > Gary Indiana
> Heavy Machinery
> Electrical
> AC Single Phase
> 240v
> UCC283 ldo regulator 3A adjustable 1.2-8.5V TO220 (X3)
UCC283 ldo regulator 3A adjustable 1.2-8.5V TO220 (X3)
3A Low Dropout Voltage Rgulator
* Precision Positive Linear Series Pass Voltage Regulation
* Quiescent Current Under 650 A Irrespective of Load
* Adjustable (5-Lead) Output Voltage Version
* Fixed (3-Lead) Versions for 3.3-V and 5-V Outputs
* Short-Circuit Power Limit of (3% VIN ISHORT)
* Low VOUT to VIN Reverse Leakage
The UCC283 3/ 5/ ADJ family of positive linear series pass voltage 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 passes 3 A while requiring only 0.45 V of typical input voltage headroom (ensured 0.6-V dropout).
These regulators include reverse voltage sensing that prevents current in the reverse direction. Quiescent current is always less than 650 A. These devices have been internally compensated in such a way 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 3.3 V and 5.0 V 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.
Short-circuit current is internally limited. The device responds to a sustained overcurrent condition by turning off after a tON time delay. The device then stays off for a period, tOFF, that is 32 times the tON delay. The device then begins pulsing on and off at the tON/(tON +tOFF) 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 tON is fixed at 750 s, on the adjustable 5-leaded versions an external capacitor sets the on time. The off time is always 32 tON. The external timing control pin, CT, on the 5-leaded versions also serves as a shutdown input when pulled low.
Internal power dissipation is further controlled with thermal overload protection circuitry. Thermal shutdown occurs if the junction temperature exceeds 165 C. The chip remains off until the temperature has dropped 20 C.
