| Patent application number | Description | Published |
| 20080211465 | Soft-stop circuit and method for a voltage regulator - A soft-stop circuit and method are provided for a voltage regulator which converts a battery voltage to an output voltage according to a feedback voltage derived from the output voltage and a reference voltage, to control the voltage regulator to enter a soft-stop state when the battery voltage is lower than a threshold level, and in which state, and the output voltage is controlled to decrease so as for the battery voltage to have a slower decreasing speed and in turn a longer battery lifetime. | 09-04-2008 |
| 20080246455 | Adaptive zero current sense apparatus and method for a switching regulator - A switching regulator includes a low-side switch having a body diode. During the low-side switch is on, a zero-current sense circuit monitors the inductor current of the switching regulator and triggers a signal to turn off the low-side switch when the inductor current falls down to a zero-current threshold, to prevent reverse inductor current from the output terminal of the switching regulator. A body-diode turn-on time controller monitors the turn-on time of the body diode and adjusts the zero-current threshold according thereto, and the turn-on time of the body diode can be reduced to an optimal interval subsequently. The self-adjustable zero-current threshold is adaptive according to the application conditions, such as the inductor size, input voltage and output voltage of the switching regulator. | 10-09-2008 |
| 20090096434 | NMOSFET-base linear charger - In an NMOSFET-base linear charger, a pair of common gate charging NMOSFET and sensing NMOSFET have their sources coupled together or virtually shorted to each other, so that these two NMOSFETs have a same gate-source voltage and thereby the sensing NMOSFET reflects the drain-source current of the charging NMOSFET on its drain-source current. From the drain-source current of the sensing NMOSFET, a current sensing signal is generated to control the gate voltage of the charging NMOSFET. By implementing the current source with NMOSFETs, the linear charger has smaller die area and less power loss. | 04-16-2009 |
| 20090237035 | Circuit and method for detecting absent battery condition in a linear charger - A circuit and method for detecting absent battery condition in a linear charger apply a detecting signal onto an output terminal of the charger and monitor the output terminal to receive a detected signal. The capacitance at the output terminal is significantly different between the presence and absence of a battery connected to the output terminal, and it is thus available to determine from the detected signal, if no battery is connected to the output terminal. | 09-24-2009 |
| 20090261654 | Power path control circuit - The present invention provides a power path control circuit comprising: an input node for receiving an external power; a first power transistor electrically connected between the input node and a first node, for controlling power supplied from the input node to the first node; a second power transistor electrically connected between the first node and a battery, for controlling power supplied from the battery to the first node; an error amplifier including an output electrically connected with a gate of the second power transistor, a first input terminal electrically connected with the first node, and a second input terminal electrically connected with the battery, wherein a voltage difference is allocated between the two input terminals. | 10-22-2009 |
| 20090315527 | Output current detection of a voltage regulator - For output current detection of a voltage regulator, the currents in a high-side transistor and a low-side transistor of the voltage regulator are sensed and summarized to a summed current to flow through a setting resistor. The voltage variation on the setting resistor is monitored to provide a feedback signal for feedback control in the voltage regulator. This detection scheme removes the current sensing resistor from the charging current path of the voltage regulator to prevent efficiency loss on it, and is much less sensitive to noise interference because greater voltage variation is available by using a greater setting resistor. | 12-24-2009 |
| 20100052629 | Adaptive zero current sense apparatus and method for a switching regulator - A switching regulator includes a low-side switch having a body diode. During the low-side switch is on, a zero-current sense circuit monitors the inductor current of the switching regulator and triggers a signal to turn off the low-side switch when the inductor current falls down to a zero-current threshold, to prevent reverse inductor current from the output terminal of the switching regulator. A body-diode turn-on time controller monitors the turn-on time of the body diode and adjusts the zero-current threshold according thereto, and the turn-on time of the body diode can be reduced to an optimal interval subsequently. The self-adjustable zero-current threshold is adaptive according to the application conditions, such as the inductor size, input voltage and output voltage of the switching regulator. | 03-04-2010 |
| 20100060233 | Charger with USB detection - A charger for a battery system detects the voltage level of a data pin of the battery system to determine whether an external power source plugged in to the battery system is a USB voltage source. When the external power source is a USB voltage source, the charger will provide power for a USB transceiver of the battery system or enable it. | 03-11-2010 |
| 20100072915 | Boost driver circuit with fast discharging function - The present invention discloses a boost driver circuit which converts an input voltage to an output voltage and supplies it to a load, the boost driver circuit comprising: a power transistor electrically connected with a node between the input voltage and the output voltage; a pulse width modulation driver circuit for controlling the operation of the power transistor; an output node electrically connected with the output voltage; a feedback node electrically connected with the load; a low voltage transistor electrically connected with the feedback node; and a clamp and fast discharge circuit electrically connected with the feedback node for discharging the feedback node when the voltage at the feedback node is higher than a predetermined voltage. | 03-25-2010 |
| 20100231047 | POWER SAFETY SYSTEM - A power safety system includes a first MOS, a second MOS, a switch and a body controller. The first MOS is connected between a power input and a power output. The second MOSFET is connected between the power output and a charging output. The switch has an end connected to the body of the first MOS, and the opposite end switched between the source and the drain of the first MOS. A body controller controls the switch according to the voltage at the power input and the voltage at the power output, to connect the body of the first MOS to the source or the drain of the first MOS. By switching the switch, the first MOS will have a parasitic diode effective to prevent a reverse current from the power output to the power input. | 09-16-2010 |
| 20110006728 | HYBRID BATTERY CHARGER AND CONTROL CIRCUIT AND METHOD THEREOF - A hybrid battery charger includes a control circuit and a power stage. The control circuit includes an error amplifier to generate a first error signal and a second error signal according to an output voltage and an output current of the hybrid battery charger, a linear controller to generate a first control signal according to the first error signal, a PWM controller to generate a second control signal and a third control signal according to the second error signal, and according to a mode signal, a multiplexer to select the first control signal for the power stage to operate the hybrid battery charger in a linear mode, or the second and third control signals for the power stage to operate the hybrid battery charger in a switching mode. | 01-13-2011 |
| 20110012565 | CHARGING CIRCUIT WITH APPLICATION SYSTEM THEREOF - A charging circuit with an application system thereof provides an error amplifier to control a transistor switch for controlling the charging power source to charges the battery. When the voltage difference between the power source and load terminals of the transistor switch drops along with the transistor switch being turned on, the output voltage of the error amplifier changes as well to increase the turning-on resistance of the transistor switch such that the voltage difference between the power source and load terminals is capable of maintaining at a value above a certain reference level for avoiding the unstable state resulting from the charging circuit being turned on and off frequently. | 01-20-2011 |
| 20110043162 | CHARGER AND PORTABLE DEVICE HAVING THE SAME - A charger for a portable device includes a USB detector connected to a data pin to detect the effective resistance on the data pin before a USB transceiver is enabled, to identify USB or adapter plug in and control a charging current for a battery accordingly. | 02-24-2011 |
| 20110080142 | Charger Circuit - A charger circuit comprising: a charging path coupled between an input voltage and a battery; a power switch on the charging path; a switch control circuit controlling the power switch; a timer counting a charging period; and a low current control circuit issuing a signal to the switch control circuit to control the power switch such that a charging current is maintained to be a predetermined low current when the timer counts to a predetermined maximum charging period. | 04-07-2011 |
| 20110095624 | Single Wire Transmission Interface And Method For the Same - The present invention discloses a single wire transmission interface comprising: a signal detection circuit detecting level switchings of a transmission signal from a single wire, and generating an enable signal and a decoded signal corresponding to the transmission signal, the level switchings including first switchings from a first level to a second level and second switchings from the second level to the first level, wherein the enable signal starts according to one first switching of the transmission signal, and stops when no first switching occur in a predetermined period after one second switching of the transmission signal, and wherein rising edges (or falling edges) of the decoded signal correspond to the first switchings of the transmission signal; a counter, under enablement by the enable signal, counting a number of the rising edges (or the rising edges) of the decoded signal or the first switchings of the transmission signal, and generating a count; a single short pulse generator generating a short pulse according to the start of the enable signal to reset the decoded signal. | 04-28-2011 |