Abstract: A MOSFET current limiting circuit, a linear voltage regulator, and a voltage converting circuit are provided. A current limiting value of the MOSFET is adjusted with the temperature or the voltage drop across the drain and the source of the MOSFET. Accordingly, it is ensured that the MOSFET operates in the safe operating area in any situation. Therefore, the MOSFET is prevented from being burnt out, and the reliability thereof is also increased.

Abstract: A controller which receives electric power required for operating through a driving voltage terminal and controls a converting circuit to convert an input voltage into an output voltage is provided. The controller is latched to stop providing a part or all of functions until the input voltage is removed. Therefore, the issues of the converting circuit in related arts in shortened life-span and safety of users due to can be avoided in the present invention.

Abstract: A LED driving circuit and a backlight module using the same are disclosed. The LED driving circuit comprises a LED module and a current controlling unit. The LED module has a plurality of the LED strings, each having a driving terminal. The current controlling unit has a plurality of current balancing terminal coupled to the driving terminal, for balancing the currents flowing through the LED strings. The current controlling unit receives a mode switch signal, controls the amount of the currents of the LED strings about a first current value when the mode switch signal represent a first mode, and controls the amount of the currents of the LED strings about a second current value when the mode switch signal represent a second mode.

Abstract: A voltage detection enabling circuit is disclosed. The voltage detection enabling circuit includes a reference voltage generating unit, an enabling protection unit, and an enabling judgment unit. The reference voltage generating unit is coupled to a driving voltage, and generates a reference voltage signal. The enabling protection unit receives the reference voltage signal and outputs an enabling judgment signal when the reference voltage signal is higher than a voltage parameter. Particularly, the voltage parameter is a component parameter of an electronic component. Then the enabling judgment unit determines whether an enabling signal is generated or not according to the enabling judgment signal and the driving voltage.

Abstract: A bias voltage is compared with a voltage difference in a detecting element according to the present invention. A bias voltage unit is coupled to the detecting element, so that they have a common voltage level to avoid noises when the circuit is operating. Accordingly, the erroneous detection caused by the noise interference can be avoided. Hence, a detecting element with a low resistance, such as an MOEFET, can be used in the present invention to decrease power consumption arisen from current detection and to further increase conversion efficiency.

Abstract: A fast current generating element in a current generating unit, used by the present invention, provides a large current for accelerating the switching of transistor switches when the transistor switches are switched. The fast current generating element includes a capacitor to provide a large differential current when a voltage level transiently changes during the switching of the transistor switches. Therefore, a transient response time of a signal transformer is shortened.

Abstract: A battery charging controlling apparatus for balancing voltages of the charged batteries is provided. The battery charging controlling includes a battery reference voltage generating unit, a voltage balancing unit, and a balance judging unit. The battery charging controlling apparatus determines whether a battery voltage difference between any two adjacent battery units of a battery module is too large or not by using a reference voltage provided from the battery reference voltage generating unit. The battery charging controlling apparatus further detects the voltage of the battery module and a charging current thereto to determine a suitable time for balancing the charged batteries. Then, the voltage balancing unit controlled by the balance judging unit allows the charging current of the lower-voltage battery unit greater than the charging current of the higher-voltage battery, unit so as to lower the battery voltage difference of the battery units.

Abstract: The present invention uses a discharge path to release the power stored in an output capacitor of a converting circuit when the time interval between two adjacent switching thereof is too long and may generate noises whose frequencies can be sensed by human ears. Hence, the present invention can keep the operating frequency of the converting circuit higher than a predetermined frequency and reduce the audio noise of the converting circuit.

Abstract: The present invention discloses a battery charging controller for achieving a balanced battery charge. The battery charging controller includes a voltage divider, a switch module and a balance circuit. A reference voltage generated by the voltage divide is used to determine which battery unit in a battery module has an insufficient voltage lower than the others, so that the balance circuit controls the switch module to allow a larger current to charge a lower-voltage battery than a higher-voltage battery, so as to result in substantially the same voltage for each fully charged battery of the battery module.