The UCC3583 is a synchronizable secondary side post regulator for preci- sion regulation of the auxiliary outputs of multiple output power supplies.
The Unitrode UCC1583, UCC2583, and UCC3583 are synchronizable secondary side post regulators designed for the precision regulation of auxiliary outputs in multiple output power supplies. These devices utilize a leading edge pulse width modulation technique to generate gate drive signals for a FET power switch connected in series with a rectifying diode. The turn-on of the power switch is delayed from the leading edge of the secondary power pulse to regulate the output voltage, preventing instability in peak current mode primary controlled systems. The controllers operate from a floating power supply referenced to the output voltage being controlled and feature undervoltage lockout, soft start, and averaging current limit amplifiers.
| Ramp Frequency, Free Running | 95 to 105 kHz |
|---|---|
| Supply Clamp Voltage | 13 to 15 V |
| Supply Current (VDD) | 3 to 5 mA |
| Gate Driver Sink/Source Capability | 0.5A Sink/1.5A Source |
| Reference Voltage (UCC3583) | 4.925 to 5.075 V |
| Storage Temperature | -65°C to +150°C |
The maximum input operating frequency for an input with a 5% to 90% duty cycle is 500 kHz.
A capacitor connected to the SS pin programs the soft start time, resulting in a slow increase in output duty cycle during startup.