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UC3823A,UC3823B/UC3825A,UC3825B pdf, datasheet
The UC3823A & B and the UC3825A & B family of PWM control ICs are improvedversions of the standard UC3823 & UC3825 family. Performance enhancementshave been made to several of the circuit blocks. Error amplifier gainbandwidth product is 12MHz while input offset voltage is 2mV. Current limitthreshold is guaranteed to a tolerance of 5%. Oscillator discharge current is specifiedat 10mA for accurate dead TIme control. Frequency accuracy is improvedto 6%. Startup supply current, typically 100mA, is ideal for off-line applicaTIons.The output drivers are redesigned to acTIvely sink current during UVLO at noexpense to the startup current specificaTIon. In addition each output is capableof 2A peak currents during transitions.Functional improvements have also been implemented in this family. TheUC3825 shutdown comparator is now a high-speed overcurrent comparator witha threshold of 1.2V. The overcurrent comparator sets a latch that ensures fulldischarge of the soft start capacitor before allowing a restart. While the fault latchis set, the outputs are in the low state. In the event of continuous faults, the softstart capacitor is fully charged before discharge to insure that the fault frequencydoes not exceed the designed soft start period. The UC3825 Clock pin has becomeCLK/LEB. This pin combines the functions of clock output and leadingedge blanking adjustment and has been buffered for easier interfacing.
