Active wire compensation circuit and controller with the same
An active wire compensation circuit, adapted to compensate a level of an output voltage detecting signal, is disclosed. A feedback controller controls a converting circuit according to the compensated output voltage detecting signal to have a load voltage for driving a load stabilized at a predetermined voltage level. The active wire compensation circuit comprises a compensating unit and a feedback compensating unit. The compensating unit detects the load current flowing through the load and accordingly generates a compensating current. The feedback compensating unit modulates the level of the output voltage detecting signal according to the compensating current and generates the compensated output voltage detecting signal.
1. An active wire compensation circuit, for compensating a level of an output voltage detecting signal, which is received by a feedback controller for controlling a converting circuit so as to have a load voltage received by a load being stabilized at a predetermined voltage level, wherein the converting circuit transforms an input voltage into an output voltage, and the output voltage is supplied to the load through a wire to generate the load voltage, the active wire compensation circuit comprising:
a compensating unit, utilized for detecting a load current and generating a compensating current accordingly, wherein the compensating unit has a current source for generating the compensating current according to the load current; and
a feedback compensating unit, modulating the level of the output voltage detecting signal according to the compensating current and outputting the compensated output voltage detecting signal accordingly, wherein the feedback compensating unit has an amplifier and a compensating resistor, the amplifier has a non-inverted input receiving the output voltage detecting signal and an inverted input receiving the compensating current, and the compensating resistor is coupled between an output of the amplifier and the inverted input to have the amplifier output the compensated output voltage detecting signal;
wherein the output voltage detecting signal is generated directly from the output voltage.
2. The active wire compensation circuit of claim 1 , wherein the compensating unit further comprises a detecting amplifier, the detecting amplifier detects the load current so as to generate an amplified detecting signal, and the current source generates the compensating current according to the amplified detecting signal.
3. A controller with active wire compensation, for controlling a converting circuit to transform an input voltage into an output voltage for driving a load, wherein the output voltage is supplied to the load through a wire to generate a load voltage, the controller with active wire compensation comprising:
an active wire compensation circuit, receiving an output voltage detecting signal responsive to the output voltage and generating a compensating current responsive to a load current through the load to compensate the output voltage detecting signal, wherein the active wire compensation circuit comprises:
a compensating unit, utilized for detecting the load current and generating the compensating current accordingly, wherein the compensating unit has a current source, which generates the compensating current according to the load current; and
a feedback compensating unit, modulating a level of the output voltage detecting signal according to the compensating current and outputting the compensated output voltage detecting signal accordingly; and
a feedback control circuit, generating at least a PWM control signal according to the compensated output voltage detecting signal to control converting operation of the converting circuit, wherein the feedback compensating unit has an amplifier and a compensating resistor, the amplifier has a non-inverted input receiving the output voltage detecting signal and an inverted input receiving the compensating current, and the compensating resistor is coupled between an output of the amplifier and the inverted input to have the amplifier output the compensated output voltage detecting signal;
wherein the output voltage detecting signal is generated directly from the output voltage.
4. The controller with active wire compensation of claim 3 , wherein the compensating unit further comprises a detecting amplifier, the detecting amplifier detects the load current and generates an amplified detecting signal accordingly, and the current source generates the compensating current according to the amplified detecting signal.