CHARGER SYSTEM FOR COMMUNICATION DEVICES

• US 20090051327A1
• Filed: 08/24/2007
• Published: 02/26/2009
• Est. Priority Date: 08/24/2007
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Bohne, William C.
• Granted Patent: US 8,900,731 B2
• Time in Patent Office: Days
• US Class Current: 320/162
• CPC Class Codes: H02J 7/00036 Charger exchanging data with battery
• CPC Class Codes: H02J 7/00047 with provisions for charging different types of batteries
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/0049 Detection of fully charged condition

Abstract

A charger system (100) for charging a battery power source for a portable host device (102) is provided. The charger system includes a charger circuit (202). The charger circuit operates to communicate a charge status. The charge status can be selected from a charge status group including a charging status and a charge completed status. Further, the charger system includes a battery (108) coupled between the portable host device and the charger circuit. The battery includes a switch circuit (206) operating to switch communication to the portable host device in response to the charge status communicated from the charge circuit. The charger system also includes the portable host device.

Claims

1. A charger system for a portable host device comprising:

a charger circuit operating to communicate a charge status, wherein the charge status is selected from a charge status group comprising;

a charging status, and

a charge completed status; and

a battery coupled between the portable host device and the charger circuit, the battery comprising;

a switch circuit operating to switch communication to the portable host device in response to the charge status communicated from the charger circuit; and

the portable host device.

2. The charger system as claimed in claim 1 wherein the charger circuit communicates the charge status by a DC voltage level charge status using a charger side communication line.

3. The charger system as claimed in claim 2, wherein the switch circuit comprises:

an output coupled to the portable host device which selectively switches a host side communication line to a ground, and

an input coupled to the charger circuit which causes the output to switch upon application of a DC voltage level of sufficient duration to exceed a time constant of an input circuit.

4. The charger system as claimed in claim 3, wherein the input of the switch circuit further allows data communication between the charger circuit and the battery via a charger side communication line without switching the host side communication line to the ground, when the DC voltage level is not of sufficient duration to exceed a time constant of an input circuit.

5. The charger system as claimed in claim 3, wherein the battery further comprises:

a first memory device for communication with the portable host device via the host side communication line.

6. The charger system as claimed in claim 5, wherein the battery further comprises:

a second memory device for communication with the charger circuit via the charger side communication line.

7. The charger system as claimed in claim 3, wherein the portable host device comprises:

a monitor for monitoring the status of the host side communication line.

8. The charger system as claimed in claim 1, wherein the battery further comprises a battery memory device to communicate pre-characterized battery design discharge profile data from the battery to the portable host device to optimize fuel gauge accuracy.

9. The charger system as claimed in claim 8, wherein the portable host device further comprises:

a means to communicate with the battery memory device.

10. The charger system as claimed in claim 1, wherein the portable host device comprises a voltage-based, multiple segment user display to present a state-of-charge information to a user of the portable host device.

11. The charger system as claimed in claim 1, wherein the portable host device is operable while coupled to the charger circuit.

12. A charger system for a portable host device comprising:

a charger circuit;

a portable host device comprising;

a pull-up host resistor that electrically couples a host side communication line to a supply voltage,

a radio data line control for detecting a state of the host side communication line, and

a display for displaying a battery charge state; and

a battery coupled between the charger circuit and the portable host device, the battery comprising;

a transistor Q1,

a first resistor R1 electrically coupled between a gate of the transistor Q1 and a second resistor R2,

the second resistor R2 electrically coupled between the first resistor R1 and ground, and

a battery EPROM U2 electrically coupled between the transistor Q1 and the ground,

wherein when the battery is attached to the portable host device and the portable host device operating without the charger circuit attached, transistor Q1 is held off by the series combination of the first resistor R1 and the second resistor R2, allowing the pull-up host resistor to bias the host side communication line high, and

further wherein the radio date line control of the portable host device is programmed to;

detect the host side communication line high,

enable radio communication with the battery EPROM, U2, and

cause the portable host device to display a battery not charging state as the state-of-charge of the battery on the display.

13. The charger circuit as claimed in claim 12, wherein the charger circuit comprises:

a pull-up charger resistor that electrically couples a charger side communication line to the supply voltage, and

a charger data line control circuit,

wherein the battery further comprises;

a diode D1 coupled between the charger side communication line and the transistor Q1,

wherein when the charger circuit is coupled to the battery and the portable host device, the pull-up charger resistor forward biases the diode D1, turning ON transistor Q1,

wherein when the transistor is turned ON, the host side communication line is biased low through a resistor R3 and the pull-up radio resistor,

further wherein the radio data line control of the portable host device is programmed to;

detect the host side communication line low,

detect the inability for radio communication with the battery EPROM, U2, and

cause the portable host device to display a battery charging state as the state-of-charge of the battery on the display.

14. The charger circuit as claimed in claim 13, wherein the battery further comprises:

a charger side EPROM, U1, and

a capacitor C1 electrically coupled in parallel to the resistor R2,

wherein the charger circuit further comprises;

a microcontroller programmed to;

read the data from the charger side EPROM, U1,

and further wherein the diode D1, the capacitor C1, and the resistor R2 form a time constant which keeps the transistor Q1 gate biased ON while the microcontroller is reading the data.