Maxim Integrated Products, Inc.

Micrel, Incorporated

Sang Hoon Kim

Kenneth Jay Helfrich

Fabrizio Fraternali

Giuseppe Patti

Described herein are systems and methods for reliably detecting of the presence or absence of accessories and other components connected to an external electrical device or connector. A low-cost detection circuit reliably distinguishes between a compromised connector and the presence of an actual device, thereby, preventing false detection scenarios. In various embodiments, the detection circuit accomplishes this by using a zero-crossing detector and/or a digital signal, which serves as a measure of impedance, to detect, within an identification period, the presence of the external device.

Systems and methods for accessory and impedance detection

A method for providing power through a USB port of an electronic device includes connecting a power supply to a USB port of an electronic device, emulating a personal computer (PC) host system such that the electronic device believes that the power supply is a PC host system, retrieving at least one descriptor from the electronic device, identifying the electronic device from the at least one descriptor, and setting a charging voltage based upon the identity of the electronic device.

Method for providing power to an electronic device

A method for accessory management and data communication between a portable electronic device and an accessory via audio port is disclosed. The method involves using a microphone line of the accessory in different communication modes including a MIC data mode and a power mode. In the MIC data mode, the MIC line disconnects from a microphone load to operate on a voltage above a predetermined threshold whenever the accessory needs to communicate with the host electronic device. In the MIC power mode, the MIC line connects with the microphone load for the normal operation of the microphone.

Accessory management and data communication using audio port

A backward compatible system and method for using 4P audio jack in an electronic device to provide power and signal to headset with active noise cancellation (ANC) as well as accessories that require an external power are disclosed. The method involves automatically deciding at the electronic device accessory type after accessory insertion detected and choosing proper accessory communication mode based at least on the decided accessory type and accessory input signal. The accessory communication mode may be an accessory power mode or an accessory microphone mode.

Backward compatible system and method for using 4P audio jack to provide power and signal to headset with active noise cancellation

In an embodiment, set forth by way of example and not limitation a USB power converter for an electronic device includes a USB bus including VBUS power line, a D&#x2212; data line and a D+ data line, a variable voltage converter, a processor clock, a USB transceiver coupled to the D&#x2212; data line and the D+ data line, and a processor coupled to processor clock and to the USB transceiver. Preferably, the variable voltage converter has an alternating current (AC) input, a direct current (DC) output coupled to the VBUS power line, and a voltage control input responsive to a voltage control signal to provide a plurality of voltage levels at the DC output. The process is, in this example embodiment, operative to develop the control signal based upon communication from an electronic device connected to the USB bus. In a non-limiting embodiment, the USB power converter further includes a host ID controller having a host ID control input coupled to the processor, the host ID controller selectively coupled to the D&#x2212; data line and the D+ data line in response to a host ID control signal developed by the processor.

Method and apparatus for providing power to an electronic device

An apparatus for remote wake-up during dedicated charging mode includes: a USB transceiver port; a USB connector port; a switch network coupling the USB transceiver port to the USB connector port; and control logic coupled to the switch network and operative to control the switch network to disconnect the USB transceiver port from the USB connector port during a dedicated charger operational mode and to connect the USB transceiver port to the USB connector port upon the detection of a potential remote wake-up condition.

Apparatus for remote wake-up during dedicated charging mode

A synchronous switching regulator controller incorporates a switch detection circuit to determine the presence or absence of a power switch at the output of a switch driver so that the switch driver can be disabled when it is left unused. In one embodiment, the synchronous controller includes a switch detection circuit receiving a power cycle signal and the PWM ramp clock signal and measuring a voltage at an output node of the switch driver. The switch detection circuit provides a driver enable signal in response to the assertion of the power cycle signal. The driver enable signal has a first logical state when the voltage at the output node of the switch driver is greater than a reference voltage and a second logical state when the voltage at the output node is less than a reference voltage. The switch driver can be disabled based on the driver enable signal.

Growing community of inventors

Grayslake, IL, United States of America

Sang Hoon Kim