US 7,622,830 B2 · Supply topology with power limiting feedback loop

Abstract

A supply topology comprising an AC to DC or DC to DC adapter and an electronic device with an active system, a battery, and an adapter controller implements closed-loop control of adapter output voltage to limit power consumption by the electronic device to a value related to maximum adapter power. The adapter couples a signal representing maximum adapter power to a control line connected to the electronic device and the electronic device couples an error signal representing the difference between instantaneous power consumption and adapter maximum power onto the same control line. The adapter adjusts its output voltage in response to the magnitude of the error signal. An adapter controller in the electronic device sets a limit for allocating current to battery charging from the signal representing maximum adapter power, with battery charging current approaching zero as instantaneous power consumption approaches maximum adapter power. The adapter controller adjusts the limit for allocating current to battery charging in response to new values of adapter maximum power associated with alternate adapters connected to the electronic device.

Claims25

Dependent claims

A power supply system, comprising:

an AC/DC or DC/DC adapter comprising circuitry for generating a reference signal representative of a limitation in an adapter output parameter;
an electronic device coupled to said adapter comprising circuitry for receiving power from said adapter, circuitry for receiving said reference signal and coupled to said adapter, circuitry for generating a second signal representative of an operating parameter of said electronic device and coupled to said circuitry for receiving power, and circuitry for generating an error signal related to an amount by which said second signal exceeds said reference signal and coupled to said circuitry for generating said second signal;
and
circuitry for modifying said adapter output parameter in response to said error signal and coupled to said circuitry for generating said error signal.

1 more element

An adapter controller for allocating power from an adapter between external electrical loads, comprising:

a first terminal, a voltage on said first input terminal related to a voltage coupled to an external electrical load;
a second terminal, the voltage difference between said first and second terminals related to a current flowing into an external electrical load;
a third terminal, a voltage related to a limit for allocating power to an external electrical load coupled to said third terminal;
a current sense amplifier with a first input connected to said first input terminal, a second input connected to said second input terminal, and a current sense output, an output signal related to the current flowing into an external electrical load coupled to said current sense output;
a power sense circuit with a first input connected to said first input line, a second input connected to said current sense output, and a power computation output, an output signal related to instantaneous power consumption by an external electrical load coupled to said power computation output;
an error amplifier with a first input connected to said power computation output, a second input connected to said control terminal, and an error output, an error signal representing the difference between said first and second inputs coupled to said error output;
and
a voltage controlled current source with a control input connected to said error output and a control signal output, an output current representing the amount by which instantaneous power consumption by an external electrical load exceeds said limit for allocating power coupled to said control signal output.

5 more elements

Dependencies are inferred from the claim text.

Supply topology with power limiting feedback loop

Life of this patent

Supply topology with power limiting feedback loop

Life of this patent

Abstract

Claims25