摘要:
The present invention relates to a power supply device generating an output power by using an AC line voltage generated through rectification of an AC input, and a driving method thereof. The power supply device controls the switching operation of the power switch by using a sensing voltage corresponding to the drain current flowing to the power switch and the feedback voltage corresponding to the output voltage. The power supply device controls the feedback current every switching cycle to generate a threshold voltage, and compares the sensing voltage and the threshold voltage to control the turn-off of the power switch. The feedback current includes the first current to generate the feedback voltage, and the threshold voltage follows a curved line waveform in which the increasing slope is decreased during the switching cycle.
摘要:
The present invention relates to a thermal shutdown unit, a switch controller including the same, and a method controlling a thermal shutdown protection operation. The present invention determines the operation state of an SMPS to vary a reference temperature for controlling a thermal shutdown protection operation according to an operation state of the SMPS.
摘要:
A current controlled switching mode power supply is provided. A turn on/off time of a switching device is adjusted by controlling a leading edge blanking (LEB) time and an external drive current of the switching device by means of a switching controller, thus capable of preventing a switching current from being excessive due to a delay of a turn-off time of the switching device, which is caused by a circuit delay during a soft start of the switching mode power supply. Also, it is possible to prevent a switching current from being excessive due to a failure of accurately controlling a turn-off time of the switching device because of a delay caused when an output voltage (a voltage at a secondary winding of a transformer) of the switching mode power supply is designed to have a high voltage.
摘要:
A CMOS transistor is provided having a relatively high breakdown voltage. The CMOS transistor includes an N-type epitaxial layer on a P-type substrate. Between the substrate and epitaxial layer are a heavily doped N-type buried layer and a heavily doped P-type base layer. An N-type sink region is proximate the edge of the NMOS region, and twin wells are in the area surrounded with the sink region. N+ source and drain regions are formed in respective wells. As the sink region is interposed between the drain and isolation regions, a breakdown occurs between the sink and isolation regions when a high voltage is applied. Twin wells are also formed in the PMOS region. P+ source and drain regions are formed in respective wells. As the N-type well surrounds the source and bulk regions, a breakdown occurs between a buried region and the isolation region when a high voltage is applied.
摘要:
The present invention relates to a switching mode power supply and a driving method thereof. In the present invention, a supply voltage is generated by using a start voltage that corresponds to input power, and a switching operation frequency of a power switch is changed according to an increase/decrease of the supply voltage.
摘要:
A switching mode power supply includes a rectifier configured to convert AC power to a first DC power, an output unit configured to convert the first DC power to a second DC power under the control of a first switch, and a pulse width modulation generator coupled to control the first switch. The pulse width modulation generator has a regulator configured to regulate the first DC power. The regulated first DC power powers the pulse width modulation generator. The regulator includes a second switch coupled to control a transmitter so that when the second switch is in a first state the transmitter transmits the first DC power to a capacitor to charge the capacitor to thereby increase the regulated first DC power, and when the switch is in a second state the transmitter does not transmit the first DC power to the capacitor to thereby allow the charge in the capacitor to reduce and in turn the regulated first DC power to reduce.
摘要:
A CMOS transistor is provided having a relatively high breakdown voltage. The CMOS transistor includes an N-type epitaxial layer on a P-type substrate. Between the substrate and epitaxial layer are a heavily doped N-type buried layer and a heavily doped P-type base layer. An N-type sink region is proximatethe edge of the NMOS region, and twin wells are in the area surrounded with the sink region. N+ source and drain regions are formed in respective wells. As the sink region is interposed between the drain and isolation regions, a breakdown occurs between the sink and isolation regions when a high voltage is applied. Twin wells are also formed in the PMOS region P+ source and drain regions are formed in respective wells. As the N-type well surrounds the source and bulk regions, a breakdown occurs between a buried region and the isolation region when a high voltage is applied.
摘要:
A high efficiency switching controller for use in a switching power supply (SPS) includes a current control device coupled to a voltage source of the SPS and a switch connected between the current control device and an output voltage circuit of the SPS. An under voltage lockout regulator coupled to the output voltage circuit of the SPS and the switch controls the state of the switch based on a voltage of the output voltage circuit and a bias unit coupled to the under voltage lockout regulator provides current to circuitry within the switching controller based on the voltage of the output voltage circuit. A protector within the high efficiency switching controller provides a control signal to the pulse width modulator unit to control the gate drive signal in response to an operating condition of the switching controller. Additionally, the control signal can periodically enable the pulse width modulator unit in response to a voltage of the output voltage circuit so that the gate drive signal includes groups of gate drive pulses.
摘要:
A switching mode power supply and a switch thereof are provided. The switch includes a plurality of first transistors, and a second transistor that is turned on/off by a control signal that is equal to that of the plurality of first transistors and in which a second current corresponding to a first current flowing to the plurality of first transistors flows, wherein a ratio of the first current to the second current sequentially changes from a time point at which the second transistor is turned on. Therefore, a switching mode power supply and a switch thereof that can always uniformly sustain a maximum limit current flowing to the switch regardless of a level of an input voltage without including a special additional circuit can be provided.
摘要:
In an EMI canceller, a control signal generation unit includes a counter, a second flip-flop, and a multiplexer. The counter outputs first and second output signals and includes first flip-flops in series. An output of the first flip-flop reverses at every cycle of the first and second output signals of a previous first flip-flop. An output of the second flip-flop reverses at every cycle of the first or second output signal of a final first flip-flop. The second flip-flop outputs third and fourth output signals. The multiplexer passes the first output signals of the first flip-flop as a control signal when the third output signal is a first level, and passes the second output signals as the control signal when it is a second level.