Low cost ultra versatile mixed signal controller circuit

A pulse width modulation controller system for control of automation circuits, AC-DC, DC-DC and power factor correction converter circuits comprising:

• an under-voltage lock-out circuit for internally supplying power to the controller system only when an external supply voltage reaches a pre-established voltage amount and shutting down the controller system's internal supply when the external supply voltage decreases down to an amount lower than another pre-established limit;
• a voltage-gap reference circuit for providing precise and stable supply voltages to circuits of the controller system;
• a driver circuit for generating square wave pulses for driving external buffers;
• an oscillator circuit for generating a voltage ramp signal for voltage mode applications, a set signal for validating each pulse of the driver circuit, and a synchronization signal for compensating delays introduced by other circuits of the controller system;
• a voltage ramp buffer circuit for buffering the voltage ramp signal having a synchronization input and an input/output circuit that allows for both voltage mode and current mode operations;
• a current spike filter circuit for eliminating current spikes included in current feedback signals, having synchronization inputs and outputs;
• an error amplifier circuit for sensing voltage signals having an amplitude higher than a pre-established limit;
• a voltage limiter circuit for limiting an output voltage from the error amplifier down to a pre-established limit;
• a PWM comparator circuit for comparing the voltage ramp signal with the signal outputted by the error amplifier and to generate a reset signal, having synchronization inputs and outputs;
• a PWM logic circuit for processing the set and reset signals and for prohibiting more than one output pulse of the driver circuit per one oscillator cycle that allows for fixed or variable frequency operation, having synchronization inputs and outputs;
• a soft start circuit for forcing the driver circuit output signal's duty cycle to increase smoothly at each when the controller system is connected to a supply source that controls, simultaneously, the error amplifier sensing input and output terminals, having synchronization inputs and outputs;
• and
• a master synchronization system for synchronizing all circuits that generate, buffer or receive voltage ramp, set and reset signals for the reset signal to switch, safely, to a LOW state before the set signal and the PWM logic circuit to deliver square wave pulses signals having any duty cycle ratio between 1% and 100% to the driver circuit.