Power Converter Responsive to Device Connection Status

1 . A power converter, comprising:

a primary controller configured to control an operating state of a first coil of a transformer such that a second coil of the transformer provides an output voltage during a standby mode of operation; and

a secondary controller configured to adjust to fluctuations in the output voltage arising during the standby mode of operation.

2 . The power converter of claim 1 ,

wherein the secondary controller adjusts for the fluctuations by communicating a compensation signal to the primary controller; and

wherein the primary controller, based upon the compensation signal received from the secondary controller, adjusts a switching cycle of the first coil to maintain the output voltage during standby mode within a predetermined voltage range.

3 . The power converter of claim 1 ,

wherein the predetermined voltage range is three to seven volts.

4 . The power converter of claim 2 ,

wherein the output voltage and the compensation signal are communicated by the secondary controller to the primary controller in a feedback signal.

5 . The power converter of claim 2 , comprising:

a feedback circuit, electrically coupled to the secondary controller and non-electrically coupled to the primary controller, configured to generate and communicate a feedback signal to the primary controller;

wherein the feedback signal is utilized by the primary controller to control the switching cycle for the first coil; and

wherein the feedback signal is adjustable by the secondary controller based on the compensation signal.

6 . The power converter of claim 5 ,

wherein the secondary controller comprises:

a compensator circuit configured to adjust the feedback signal based on a reference voltage signal.

7 . The power converter of claim 1 , comprising:

a monitoring circuit configured to monitor the output voltage and generate a reference voltage signal for use by the secondary controller in adjusting for fluctuations in the output voltage during the standby mode of operation.

8 . The power converter of claim 7 ,

wherein the monitoring circuit is coupled to a compensator circuit having a first capacitance providing a set threshold for comparison with the reference voltage signal.

9 . The power converter of claim 8 ,

wherein the monitoring circuit comprises a voltage divider circuit having:

a first resistor having a first terminal coupled to a first node and a second terminal;

wherein the fluctuations in the output voltage are detectable at the first node;

a second resistor coupled to the second terminal and to a ground potential; and

wherein the reference voltage signal is generated at the second terminal.

10 . The power converter of claim 9 , comprising:

a compensator circuit configured to compare the reference voltage signal to a threshold and, based on the comparison, output a compared signal;

wherein the compared signal is communicated by the secondary controller to the primary controller using a feedback circuit; and

wherein the threshold is pre-set.

11 . The power converter of claim 7 , comprising:

a third resistor having a third resistance coupled to a feedback circuit;

wherein an adjustment signal is communicated in a feedback signal;

wherein a compensator circuit is configured to:

adjust the feedback signal based upon whether a device is connected to the power converter;

after the device is connected to the power converter, first adjust the adjustment signal by decreasing the third resistance; and

after the device is disconnected from the power converter, second adjust the adjustment signal by increasing the third resistance

12 . The power converter of claim 1 ,

wherein, when a device is not connected to the power converter, the primary controller first responds to the fluctuations in the output voltage at a substantially slower rate as compared with a second response of the primary controller to second fluctuations in the output voltage when the device is connected to the power converter.

13 . The power converter of claim 1 , comprising:

a secondary wake-up circuit configured to detect when a device is connected to the power converter based upon changes in a device voltage potential detectable at a port of the secondary controller;

wherein, when the device is connected to the port, a device resistance provided by the device and a fourth resistance provided by the power converter form a voltage divider circuit which changes the device voltage potential at the port.

14 . A circuit, comprising:

an amplifier configured to:

receive a reference voltage signal;

receive a threshold voltage;

compare the reference voltage signal to the threshold voltage; and

based on the comparison, output an adjustment signal;

wherein the reference voltage signal is representative of an output voltage of a power converter;

wherein the adjustment signal is used by a primary controller to control fluctuations in the output voltage while the power converter operates in standby mode.

15 . The circuit of claim 14 ,

wherein the threshold voltage is selected based upon an observed response of the power converter over a range of output voltages.

16 . The circuit of claim 14 , further comprising:

a port connecting the circuit with a feedback circuit;

a resistor, having a variable resistance, electrically coupling outputs of the amplifier, via a first port, with the feedback circuit; and

an attachment detector configured to adjust the variable resistance of the resistor;

wherein, adjustments in the variable resistance of the resistor result in adjustments in the adjustment signal; and

wherein, when the variable resistance is increased, the primary controller responds to the fluctuations in the output voltage at a slower rate than otherwise occur when the variable resistance is decreased.

17 . The circuit of claim 16 ,

wherein the variable resistance is increased when an adaptive device is attached to the power converter; and

wherein the variable resistance is decreased when the adaptive device is detached from the power converter.

18 . A method, comprising:

comparing a reference voltage to a threshold voltage to generate an adjustment signal;

wherein the reference voltage is representative of an output voltage of a power converter;

communicating the adjustment signal to a primary controller for the power converter; and

modifying, based on the adjustment signal and by the primary controller, a switching cycle for a first coil of the transformer;

wherein one or more modifications of the switching cycle are used by the primary controller to compensate for fluctuations in the output voltage arising while the power converter is in standby mode.

19 . The method of claim 18 ,

wherein the power converter includes a primary side and a secondary side;

wherein the primary controller is located on the primary side;

wherein the primary side is electrically connected to an electrical power source during the standby mode of operation;

wherein the secondary side is electrically couplable to the adaptive device;

wherein the comparing operation occurs on the secondary side of the power converter;

and

wherein the adjustment signal is communicated by the secondary side to the primary side using a feedback circuit.

20 . The method of claim 19 ,

wherein prior to communicating the adjustment signal to the primary side, the method further comprises:

when the adaptive device is connected to the power converter, first modifying the adjustment signal; and

when the adaptive device is disconnected from the power converter, second modifying the adjustment signal;

wherein the first modifying results in the primary controller responding more slowly to the fluctuations in the output voltage; and

wherein the second modifying results in the primary controller responding more quickly to the fluctuations in the output voltage.