Abstract:
A wall control interface for power management includes a transmitting circuit that generates a switching signal to control a switch and achieve a phase modulation to a power line signal in response to a transmitting-data. A receiving circuit is coupled to detect the phase of the power line signal for generating a data signal and a receiving-data in response to the phase of the power line signal. The receiving circuit further generates a control signal to control power of a load in accordance with the data signal or the receiving-data. The phase modulation is achieved by controlling a turn-on angle of the power line signal. The switch remains in a turn-on state during the normal condition, which achieves good power and low current harmonic. The phase modulation is only performed during the communication of the power management.
Abstract:
A power supply system is introduced herein. The power supply system includes a power converter to supply a power source to an electronic circuit through an output cable of the power supply. A communication unit is coupled to the output cable of the power supply to develop a communication channel between the power converter and the electronic circuit in order to report the status of the power converter to the electronic circuit.
Abstract:
A switching controller having switching frequency hopping for a power converter includes a first oscillator generating a pulse signal and a maximum duty-cycle signal for determining a switching frequency of a switching signal, a pattern generator having a second oscillator and generating a digital pattern code in response to a clock signal, a programmable capacitor coupled to the pattern generator and the first oscillator for modulating the switching frequency of the switching signal in response to the digital pattern code, and a PWM circuit coupled to the first oscillator for generating the switching signal in accordance with the maximum duty-cycle signal. A maximum on-time of the switching signal is limited by the maximum duty-cycle signal. The switching signal is utilized to switch a transformer of the power converter.
Abstract:
An electrostatic discharge (ESD) protection device with adjustable single-trigger or multi-trigger voltage is provided. The semiconductor structure has multi-stage protection semiconductor circuit function and adjustable discharge capacity. The single-trigger or multi-trigger semiconductor structure may be fabricated by using the conventional semiconductor process, and can be applied to IC semiconductor design and to effectively protect the important semiconductor devices and to prevent the semiconductor devices from ESD damage. In particular, the present invention can meet the requirements of high power semiconductor device and has better protection function compared to conventional ESD protection circuit. In the present invention, a plurality of N-wells or P-wells connected in parallel are used to adjust the discharge capacity of various wells in the P-substrate so as to improve the ESD protection capability and meet different power standards.
Abstract:
The present invention provides a primary-side flyback power converter that supplies a constant voltage output and a constant current output. To generate a well-regulated output voltage under varying load conditions, a PWM controller is included in the power converter in order to generate a PWM signal controlling a switching transistor in response to a flyback voltage sampled from a first primary winding of the power supply transformer. Several improvements are included in this present invention to overcome the disadvantages of prior-art flyback power converters. Firstly, the flyback energy of the first primary winding is used as a DC power source for the PWM controller in order to reduce power consumption. A double sample amplifier samples the flyback voltage just before the transformer current drops to zero. Moreover, an offset current is pulled from a detection input of the double sample amplifier in order to generate a more accurate DC output voltage. The offset current is generated in response to the temperature in order to compensate for temperature-induced voltage fluctuations across the output rectifier. Ultimately, in order to maintain a constant output current, the PWM controller modulates the switching frequency in response to the output voltage.
Abstract:
A method of manufacturing different-voltage devices mainly comprises forming at least one high-voltage well in high-voltage device regions, at least one N-well in low-voltage device regions, at least one P-well in low-voltage device regions, source/drain wells in high-voltage device regions, and isolation wells in isolation regions in a p-type substrate. The breakdown voltage is adjusted by modulating the ion doping profile. Furthermore, parameters of implanting conductive ions are adjusted for implanting conductive ions into both high-voltage device regions and low-voltage device regions. The isolation wells formed in isolation regions between devices are for separating device formed over high-voltage device regions and device formed over low-voltage device regions. The thickness of a HV gate oxide layer is thicker than the thickness of an LV gate oxide layer for modulating threshold voltages of high-voltage devices and low-voltage devices.
Abstract:
A method and apparatus to dynamically modify internal compensation of a low dropout (LDO) voltage regulator is provided. The LDO voltage regulator includes an output pass transistor, an error amplifier, a bias transistor and a compensation network. The compensation network is connected between a gate and a drain of the output pass transistor to compensate for the feedback loop. The compensation network and the bias transistor generate pole-zero pairs to perform a maximum 45 degrees phase shift before reaching the crossover frequency in the LDO voltage regulator. Therefore a minimum 45 degrees phase margin is provided for the feedback loop in various load conditions. Furthermore, the pole-zero pairs produced in the LDO voltage regulator are adaptively adjusted according to load conditions, so that the bandwidth is optimized and faster transient response is achieved.
Abstract:
A high voltage LDMOS transistor according to the present invention includes a P-field and divided P-fields in an extended drain region of a N-well. The P-field and divided P-fields form junction-fields in the N-well, in which a drift region is fully depleted before breakdown occurs. Therefore, a higher breakdown voltage is achieved and a higher doping density of the N-well is allowed. Higher doping density can effectively reduce the on-resistance of the LDMOS transistor. Furthermore, the N-well generated beneath a source diffusion region provides a low-impedance path for a source region, which restrict the transistor current flow in between a drain region and a source region.
Abstract:
A high voltage LDMOS transistor according to the present invention includes P-field blocks in the extended drain region of a N-well. The P-field blocks form the junction-fields in the N-well for equalizing the capacitance of parasitic capacitors between the drain region and the source region and fully deplete the drift region before breakdown occurs. A higher breakdown voltage is therefore achieved and the N-well having a higher doping density is thus allowed. The higher doping density reduces the on-resistance of the transistor. Furthermore, the portion of the N-well generated beneath the source diffusion region produces a low-impedance path for the source region, which restricts the transistor current flow in between the drain region and the source region.
Abstract:
A primary-side flyback power converter supplies a constant voltage and a constant current output. To generate a well-regulated output voltage under varying load conditions, the power converter includes a PWM controller. The PWM controller generates a PWM signal to control a switching transistor in response to a flyback voltage detected from the first primary winding of the power supply transformer. To reduce power consumption, the flyback energy of the first primary winding is used as a DC power source for the PWM controller. The flyback voltage is sampled following a delay time to reduce interference from the inductance leakage of the transformer. To generate a more accurate DC output voltage, a bias current is pulled from the detection input to form a voltage drop across a detection resistor for compensating for the voltage drop of the output rectifying diode.