Method and apparatus for operating an internal charger system of a portable electronic device

Patent metadata

Field	Value
Publication number	US-9843220-B2
Application number	US-201514607651-A
Country	US
Kind code	B2
Filing date	Jan 28, 2015
Priority date	Jan 28, 2015
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

An internal charging system controls charging of a battery used to power an electronic device when an external power source is connected to the device. The internal charging system can charge a battery that has a higher operating voltage than the voltage provided by the external power source. While charging the battery from the external power source, an internal charge controller can operate and inhibit functions of the device to indicate to user that a charging operation is commencing, and to prevent operation of the device when the battery voltage is too low to support such operation.

First claim

We claim:

1. An internal charger system for an electronic device, comprising:
an internal charge controller that determines a maximum current output of an external power source connected to the electronic device at a standardized data connector and a selected current rate based at least in part on the maximum current output of the external power source and charging parameters retrieved from the battery;
a single-stage direct current (DC) to DC regulator coupled to the standardized data connector that generates the selected current rate from the external power source at a charging voltage, wherein the charging voltage is based on a battery voltage of a battery connected to the electronic device; and
the internal charge controller is coupled to the single-stage DC to DC regulator and controls the single-stage DC to DC regulator to charge the battery connected to the electronic device at the charging voltage and at the selected current rate according to a charge regime controlled by the internal charge controller.

2. The internal charger system of claim 1 , wherein the electronic device further comprises a dedicated set of charging contacts to allow an external battery charger to charge or discharge the battery, the internal charge controller is coupled to the dedicated set of charging contacts and monitors charging of the battery by the external battery charger and reports battery charge status to a host processor of the electronic device.

3. The internal charger system of claim 1 , wherein the single-stage DC to DC regulator is a single stage buck/boost regulator.

4. The internal charger system of claim 1 , wherein the single-stage DC to DC regulator is a buck regulator.

5. The internal charger system of claim 1 , wherein the single-stage DC to DC regulator is a linear regulator.

6. The internal charger system of claim 1 , further comprising:
a mask circuit that is enabled by the internal charge controller to prevent a power management circuit of the electronic device from being turned by or responsive to a user input when the battery voltage indicates the battery is below a low voltage threshold.

7. The internal charger system of claim 6 , wherein the battery voltage rising above a low voltage threshold, the internal charge controller commands the electronic device to a limited turn-on state, the method further comprising:
disabling the mask circuit; and
enabling a visual indicator of the electronic device to indicate that the battery is being charged, after the mask is removed.

8. The internal charger system of claim 1 , further comprising:
a voltage source that is connected to a host processor of the electronic device and to the internal charge controller, and that provides power to the host processor when the electronic device is turned on, wherein the host processor communicates with a power management circuit when it is powered by the voltage source;
the internal charger system further comprises a turn-on circuit that is connected to the power management circuit, wherein the internal charge controller enables the turn on circuit to provide a limited turn-on signal to the power management circuit when power from the voltage source to the host processor is turned off responsive to a user input while the external power source is connected to the standardized data connector.

Assignees

• Motorola Solutions Inc

Inventors

• Herrmann John E
• Bartels Peter J
• Geren Michael D
• Kerfoot Jr Roy L

Classifications

• H02J7/96

  in response to battery voltage · CPC title

• H02J7/94

  in response to battery current · CPC title

• H02J2207/30

  Charge provided using DC bus or data bus of a computer · CPC title

• H02J7/00

  Circuit arrangements for charging or discharging batteries or for supplying loads from batteries · CPC title

• H02J9/002 Primary

  in which a reserve is maintained in an energy source by disconnecting non-critical loads, e.g. maintaining a reserve of charge in a vehicle battery for starting an engine · CPC title