Pwm controller for compensating a maximum output power and power supply convertor

Abstract

The invention relates to a PWM controller for compensating a maximum output power and a power converter. The power converter includes a power switch and a PWM controller; the PWM controller comprises a control circuit, an oscillator and a frequency modulator. The control circuit generates a PWM signal in response to the pulse signal generated by the oscillator. The frequency modulator generates a second discharge signal to the oscillator for controlling the maximum output power of the power converter. The second discharge signal is decreased for prolonging a switching period of the PWM signal under a high-line voltage of the power converter. The invention adopts the frequency modulator capable of prolonging the exchanging period of PWM signal under the higher input voltage, which is able to compensate the difference caused by the input voltage and the delay time, thereby having the same maximum output power no matter the low input voltage or the high input voltage under the heavy-load.

Description

technical field [0001] The invention relates to a pulse width modulation controller and a power converter, in particular to a pulse width modulation controller and a power converter with a frequency modulator for compensating the maximum output power of the switching power converter. Background technique [0002] Power converters are generally used to provide power to various electronic devices. Pulse Width Modulation technology is a conventional technology in power converters, which can control and adjust the output power of the power converter. Various protection features are built into the power converter to protect the power converter from permanent damage. Among them, the function of compensating the maximum output power is generally used for overload and short circuit protection. [0003] see figure 1 Shown is a circuit diagram of a prior known power converter in the prior art. Existing known power converters, including transformer T 1 , Transformer T 1 With prim...

AI Technical Summary

Problems solved by technology

[0012] It can be seen that the above-mentioned existing pulse width modulation controller and power converter obviously still have inconvenience and defects in structure and use, and need to be further improved urgently.

In order to solve the above-mentioned problems, the relevant manufacturers have tried their best to find a solution, but for a long time no suitable design has been developed, and the general products do not have a suitable structure to solve the above-mentioned problems. This is obviously related The problem that the industry is eager to solve

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