Shared interface device

• US 20030076243A1
• Filed: 10/23/2001
• Published: 04/24/2003
• Est. Priority Date: 10/23/2001
• Status: Active Grant

• Current Assignee: EJT Technologies Incorporated
• Original Assignee: Lite-On Technology Corporation
• Inventors: Chen, Chien Chih, Lin, Wen Kuan
• Granted Patent: US 6,781,525 B2
• Time in Patent Office: Days
• US Class Current: 341/22
• CPC Class Codes: G06F 1/266 Arrangements to supply power to external peripherals either directly from the computer or under computer control, e.g. supply of power through the communication port, computer controlled power-strips
• CPC Class Codes: H04M 1/72409 by interfacing with external accessories hands-free H04M1/60

Abstract

A shared interface device provides connection between a portable electronic device and a peripheral unit. The shared interface device comprises a switch and an energy-storing element. The switch has a terminal connected to a T×D/POWER pin of the portable electronic device and an R×D pin of the peripheral unit, and another terminal connected to a VCC pin of the peripheral unit. The switch is ON/OFF when the T×D/POWER pin of the portable electronic device is HI/LO. The energy-storing element has one end connected to another end of the switch to supply electrical power to the peripheral unit and another end connected to ground. The energy-storing element is charged when the switch is ON and used as a backup power supply when the switch is OFF.

Claims

1. A shared interface device providing connection between a portable electronic device and a peripheral unit, the portable electronic device having a plurality of pins with one pin assigned with transmitting data/power supplying function (T×

D/POWER pin), the peripheral unit having a plurality of pins with one pin assigned with receiving data function (R×

D pin);

the shared interface device comprising

a switch having at least two terminals, the switch having a first terminal connected to the T×

D/POWER pin of the portable electronic device and the R×

D pin of the peripheral unit, the switch being ON when the T×

D/POWER pin of the portable electronic device is HI and being OFF when the T×

D/POWER pin of the portable electronic device is LO;

an energy-storing element with a first end connected to a second terminal of the switch to supply electrical power to the peripheral unit and a second end connected to ground, the energy-storing element being charged when the switch is ON and used as a backup power supply when the switch is OFF.

2. The shared interface device as in claim 1, wherein the switch is a diode having an anode connected to the T×

D/POWER pin of the portable electronic device and the R×

D pin of the peripheral unit, and a cathode connected to a power source (VCC) pin of the peripheral unit.

3. The shared interface device as in claim 1, wherein the switch is a PNP transistor having a base connected to one end of a resistor and another end of the resistor connected to ground, the PNP transistor further having a collector connected to a power source (VCC) pin of the peripheral unit, and an emitter connected to the T×

D/POWER pin of the portable electronic device and the R×

D pin of the peripheral unit.

4. The shared interface device as in claim 1, wherein the energy-storing element is a capacitor.

5. The shared interface device as in claim 1, wherein the portable electronic device is one of a personal digital assistant and a cellulous phone.

6. The shared interface device as in claim 1, wherein the peripheral unit is a keyboard.