Unlock instant, AI-driven research and patent intelligence for your innovation.

Electronic device power protection circuitry

A technology for electronic equipment and protection circuits, applied in 0002] The present invention relates to the field of electronic equipment as a whole, and can solve problems such as host equipment damage

Active Publication Date: 2015-02-04
APPLE INC
View PDF6 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This behavior, which is sometimes called back powering, can cause damage to the host device

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Electronic device power protection circuitry
  • Electronic device power protection circuitry
  • Electronic device power protection circuitry

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0024] figure 1 An exemplary system including an electronic device with a protection circuit is shown in . Such as figure 1 As shown in , system 8 may include a host device, such as electronic device 10, and an accessory device, such as electronic device 14 or other external device. Path 12 may be used to couple devices 10 and 14 . Path 12 may include power lines, such as positive power line 16 through which positive power supply current flows and ground power line 17 through which ground power supply current flows. Path 12 may also include analog signal lines and / or digital signal lines (eg, pairs of data lines, etc.). When power is being transferred from host 10 to accessory 14, the current I flowing through line 16 will be positive.

[0025] Device 10 may have an input-output port with input-output power terminals T1 and T2. Device 14 may have an input-output port with input-output power terminals T3 and T4. Terminals T1 and T3 may be positive supply terminals. Termi...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

A host electronic device may be coupled to an accessory electronic device. During normal operation, the host device may supply the accessory device with power over a power supply line. Back-powering events in which the accessory device delivers power to the host device may be prevented by interposing a protection transistor in the power supply line. A current mirror may be formed using the protection transistor and an additional transistor that produces a sense current proportional to the amount of current that is flowing through the power supply line. A current -to- voltage amplifier may produce a sense voltage that is proportional to the sense current. A bias circuit may be used to bias the sense current through the current mirror. A control circuit may compare the sense voltage to one or more reference voltages and turn off the protection transistor when appropriate to prevent back- powering of the host device.

Description

[0001] This patent application claims U.S. Patent Application 13 / 629,276, filed September 27, 2012, U.S. Provisional Patent Application 61 / 660,634, filed June 15, 2012, and U.S. Provisional Patent Application 61 / 664,691, filed June 26, 2012 priority of the patent application, which is hereby incorporated by reference in its entirety. Background technique [0002] The present invention relates generally to electronic devices, and more particularly, to power protection circuits for electronic devices. [0003] Electronic devices such as cellular phones, media players, tablet computers, and other devices are often coupled to accessories. For example, an accessory device may have a display, speakers, or other components that the host electronic device may use when playing media files or other content for the user. [0004] During normal operation, the host device can supply power to the accessory. If the accessory is defective or poorly designed, the accessory may supply power t...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): H02H3/18G01R19/00G01R19/14
CPCH02H3/18G05F3/26G01R19/00G01R19/14Y02E10/56
Inventor R·保罗Y·佩雷斯S·赫林亚E·肖克赫特
Owner APPLE INC