Single wire radio to charger communications method

• US 6,300,743 B1
• Filed: 03/08/2000
• Issued: 10/09/2001
• Est. Priority Date: 03/08/2000
• Status: Expired due to Term

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Coapstick, Ronald, Desai, Vijaykumar D., Patino, Joseph
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): LUK, LAWRENCE W
• Application Number:
  US09/521,151
• Time in Patent Office: 580 Days
• Field of Search: 320/106, 320/129, 320/130, 320/145, 320/125, 320/138, 320/140
• US Class Current: 320/106
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge

Abstract

This invention is a single wire interface communication system whereby a phone having internal charging circuitry communicates the charging status of the battery attached to the phone by varying the duty cycle of a pulse with a predetermined period across the single wire interface. In a preferred embodiment, the predetermined pulse of time T, where T is 1 second, is divided into N divisions, where N equals 10. A duty cycle high for time T/N and low for time 9T/N represents a first charging state; a duty cycle high for time 2T/N and low for time 8T/N corresponds to a second charging state; and so on. The system allows for information to be transmitted across a single wire, thereby freeing data connections for other accessories.

Claims

1. A method of communicating battery charging status from a phone to a charger, the method comprising the steps of:

A. providing a power supply which can be coupled to a charger for supplying voltage and current;

B. providing a charger having

i. a microprocessor;

ii. at least one pocket for receiving a phone with a battery attached;

iii. a first set of contacts for supplying a voltage and current;

iv. a single wire interface coupled to the microprocessor;

v. a charger contact coupled to the single wire interface;

vi. a pull-up resistor coupled between the single wire interface and a positive voltage;

vii. an identification display means capable of being driven into different states by the microprocessor;

C. providing a phone having

i. charging circuitry disposed therein;

ii. a battery;

iii. electrical contacts coupled to the charging circuitry for receiving voltage and current; and

iv. a phone contact for the single wire interface coupled to the charging circuitry;

D. wherein the charging circuitry communicates battery charging status to the microprocessor by varying the duty cycle of a pulse with a predetermined period across the single wire interface.

2. The method of claim 1, further wherein the predetermined period is divisible by ten.

3. The method of claim 2, further wherein when the pulse is high for one-tenth of the period and low for nine-tenths of the period, a first charging state is represented, causing the microprocessor to drive the identification display means into a first state.

4. The method of claim 3, further wherein when the pulse is high for two-tenths of the period and low for eight-tenths of the period, a second charging state is represented, causing the microprocessor to drive the identification display means into a second state.

5. The method of claim 4, further wherein when the pulse is high for three-tenths of the period and low for seven-tenths of the period, a third charging state is represented causing the microprocessor to drive the identification display means into a third state.

6. The method of claim 5, further wherein when the pulse is high for four-tenths of the period and low for six-tenths of the period, a fourth charging state is represented causing the microprocessor to drive the identification display means into a fourth state.

7. The method of claim 6, further wherein when the pulse is high for five-tenths of the period and low for five-tenths of the period, a fifth charging state is represented causing the microprocessor to drive the identification display means into a fifth state.

8. The method of claim 7, further wherein when the pulse is high for six-tenths of the period and low for four-tenths of the period, a sixth charging state is represented causing the microprocessor to drive the identification display means into a sixth state.

9. The method of claim 8, further wherein when the pulse is high for seven or more tenths of the period, a seventh charging state is represented causing the microprocessor to drive the identification display means into a seventh state.

10. The method of claim 9, wherein the identification display means is a light emitting diode.

11. The method of claim 10 wherein the first state of the identification display means is the light emitting diode illuminated solid red.

12. The method of claim 11 wherein the second state of the identification display means is the light emitting diode illuminated solid yellow.

13. The method of claim 12 wherein the third state of the identification display means is the light emitting diode illuminated flashing green.

14. The method of claim 13 wherein the fourth state of the identification display means is the light emitting diode illuminated solid green.

15. The method of claim 14 wherein the fifth state of the identification display means is the light emitting diode illuminated flashing yellow.

16. The method of claim 15 wherein the sixth state of the identification display means is the light emitting diode illuminated flashing red.

17. The method of claim 16 wherein the seventh state of the identification display means is the light emitting diode turned off.