Patent application number | Description | Published |
20080211470 | Auto discharge linear regulator and method for the same - The present invention discloses an auto discharge linear regulator comprising: a basic linear regulator for converting an input voltage to an output voltage at an output node; a load detector circuit for detecting the load condition at the output node; and an discharge control circuit under control by the load detector circuit for discharging the voltage at the output node. | 09-04-2008 |
20090102431 | Universal serial bus charger circuit and charging method - The present invention discloses a universal serial bus (USB) charging circuit, comprising: a charging path for charging a battery from a USB host; a charging switch located on the charging path; a current sensing circuit for sensing current information on the charging path; a maximum available current detection circuit for detecting the maximum available current from the USB host; and a loop controller circuit for controlling the charging switch so that the charging current on the charging path is substantially equal to the maximum available current detected by the maximum available current detection circuit, wherein the maximum available current detection circuit detects the maximum available current during circuit initialization and stores it. | 04-23-2009 |
20090174388 | Dual power switch and voltage regulator using same - The present invention discloses a dual power switch and a voltage regulator using the dual power switch. The dual power switch comprises a PMOS power switch and an NMOS power switch connected in parallel and operating according to corresponding predetermined conditions, respectively. | 07-09-2009 |
20100054313 | Single-wire transmission interface and method of transmission through single-wire - The present invention discloses a single-wire transmission interface, and a method of transmission through single-wire. The method comprises: providing a single-wire signal through a single-wire; and transmitting information only in a transmission period defined by a fixed first time period starting from one of a rising or a falling edge of the single-wire signal. | 03-04-2010 |
20110001461 | Buck-boost switching regulator and control circuit and method therefor - The present invention discloses a buck-boost switching regulator, and a control circuit and a method therefor, to convert an input voltage to an output voltage. The control method comprises: obtaining a feedback signal relating to the output voltage; comparing the feedback signal with a reference voltage to generate an error amplified signal; when the error amplified signal is between a first voltage (V | 01-06-2011 |
Patent application number | Description | Published |
20090212841 | LEVEL SHIFT CIRCUIT AND METHOD FOR THE SAME - The present invention discloses a level shift circuit which comprises: an input driver circuit; a capacitor having a first end electrically connected with the output of the input driver circuit; an output driver circuit electrically connected with a second end of the capacitor; and a feedback latch circuit electrically connected between the output of the output driver circuit and the second end of the capacitor, for maintaining the voltage level at the second end of the capacitor. | 08-27-2009 |
20090219078 | CHARGE PUMP DOWN CIRCUIT AND METHOD FOR THE SAME - The present invention discloses a charge pump down circuit which comprises three capacitors operating in three time phases. In the first time phase, the total of the voltages across the three capacitors is equal to an input voltage; in the second time phase, the voltage across the second capacitor is equal to the voltage across the third capacitor; in the third time phase, the difference between the voltages across the first and the second capacitors is equal to the voltage across the third capacitor, wherein the voltage across the third capacitor is the output voltage of the charge pump down circuit. | 09-03-2009 |
20100066312 | Overvoltage protection circuit for use in charger circuit system and charge circuit with overvoltage protection function - The present invention discloses an overvoltage protection (OVP) circuit for use in a charger circuit system, comprising: a power transistor electrically connected between a voltage supply and a battery; an OVP circuit which turns off the transistor when a voltage supply exceeds a threshold value; and a multiplexing circuit electrically connected between an output of the OVP circuit and the gate of the transistor. The present invention also discloses a charger circuit with an OVP function, comprising: a single power transistor electrically connected between a voltage supply and a battery; an OVP control circuit which turns off the power transistor when a voltage supply exceeds a threshold value; and a charger control circuit which controls the gate of the power transistor to determine a charge current to the battery when the voltage supply does not reach the threshold value. | 03-18-2010 |
20120139443 | LIGHT EMITTING DIODE DRIVING APPARATUS - A light emitting diode (LED) driving apparatus is provided, and which includes a first operational amplifier (OPA) having a positive input terminal receiving a predetermined voltage related to a current flowing through an LED string; a first resistor having a first end coupled to a negative input terminal of the first OPA and a second end coupled to a ground; a power transistor having a gate coupled to an output of the first OPA, a drain coupled to a cathode of the LED string and a source coupled to the first end of the first resistor; an error amplifier having a first input terminal coupled to the gate of the power transistor, a second input terminal receiving a reference voltage and an output terminal outputting a control voltage; and a power conversion stage providing a DC voltage to an anode of the LED string according to the outputted control voltage. | 06-07-2012 |