Patent application number | Description | Published |
20080278872 | Electrostatic Discharge Protection Circuit - Techniques pertaining to designs of ElectroStatic Discharge (ESD) protection circuits are disclosed. In one embodiment, an ESD protection circuit combines a substrate-driving technique with a gate-driving technique to ease the ESD design and save the silicon area. In another embodiment, an ESD protection circuit is based on a Positive Metal Oxide Semiconductor field effect transistor (PMOS) in a standard Complementary Metal Oxide Semiconductor (CMOS) process. In another embodiment, the ESD protection circuit is based on a negative Metal Oxide Semiconductor field effect transistor (NMOS) in the standard CMOS process. Depending on implementation, the ESD protection circuit is implemented for a negative voltage input pin, a normal input pin, and a power supply clamp circuit. | 11-13-2008 |
20080284394 | Low dropout voltage regulator with improved voltage controlled current source - Techniques pertaining to designs of a compensation voltage controlled current source (VCCS) used in low dropout voltage regulators are disclosed. According to one aspect of the present invention, a compensation voltage controlled current source (VCCS) is so designed to meet the low input/output voltage requirements. Various features of the VCCS are demonstrated through several embodiments. | 11-20-2008 |
20080284395 | Low Dropout Voltage regulator - Techniques pertaining designs of LDO voltage regulators are described. According to one design, the LDO voltage regulator comprises: a differential amplifier circuit having a pair of input terminals and an output terminal, one of the input terminals coupled to a predetermined reference voltage; an intermediate amplifier circuit having an output terminal and an input terminal coupled to the output terminal of the differential amplifier circuit; and an output pass circuit comprising a pass transistor, an output resistor and an output capacitor, the pass transistor having a control terminal coupled to the output terminal of the intermediate amplifier circuit, an input terminal coupled to a power supply and an output terminal coupled to one terminal of the output resistor, the other terminal of the output resistor taken as a voltage output node, the output capacitor coupled between the voltage output node and a ground reference; a feedback circuit including a pair of ladder resistors coupled in series between the voltage output node and the ground reference, a node between the ladder resistors coupled to the other one of the input terminals of the differential amplifier circuit; and a voltage controlled current source circuit having an input terminal coupled to a node between the pass transistor and the output resistor of the output pass circuit and an output terminal coupled to the node between the ladder resistors. | 11-20-2008 |
20090128107 | Low Dropout Voltage Regulator - Improved designs of an LDO voltage regulator with ultra low quiescent current are disclosed. According to one embodiment, an LDO voltage regulator is designed to completely cancel an intermediate gain stage while decreasing a quiescent current and to stabilize a loop circuit by means of two zeros introduced in a frequency transfer function thereof. Such a LDO voltage regulator does not increase the power consumption and applicable in many circuits used in electronic devices. | 05-21-2009 |
20090167197 | Driver and method for driving LEDS on multiple branch circuits - Techniques pertaining to driving LEDs on multiple branches of a circuit are disclosed. According to one aspect of the present invention, an LED drive circuit includes a boost circuit configured for receiving an input voltage and providing an output voltage according to a control signal, a selector configured for alternatively selecting one of the feedback signals as an output feedback signal and switching on a corresponding branch circuit, and a pulse-width modulation (PWM) controller configured for generating a pulse-width modulation signal as the control signal for the boost circuit according to the output feedback signal of the selector, essentially to match respective currents in the multiple branches. | 07-02-2009 |
20090167263 | Current limiting circuit and voltage regulator using the same - Techniques pertaining to a voltage regulator with a current limiting circuit having low quiescent current are disclosed. According to one aspect of the present invention, a current limiting circuit is provided for limiting a current passing through an output pass circuit of a voltage regulator, the current limiting circuit comprises: a current sampling circuit for sampling the current passing through the output pass circuit to obtain a duplicated current being proportional to the current passing through the output pass circuit; a current mirror circuit for producing a mirror current being proportional to the duplicated current with the duplicated current as a reference current; a current to voltage converter for producing a voltage being proportional to the mirror current; and a voltage comparator for comparing the voltage produced by the current to voltage converter with a threshold voltage and turning off the output pass circuit when the voltage produced by the current to voltage converter is larger than or equal to the threshold voltage. | 07-02-2009 |
20100259237 | Compensation Circuit - An improved compensation circuit with loop compensation is disclosed. The compensation circuit can get an equivalent large capacitance by amplifying a small capacitor. Hence, the compensation circuit can get a good compensation effect with a minimum chip area, hence lower cost. | 10-14-2010 |
20100264881 | Battery Protection Circuit - A battery protection circuit with quickly testable design is disclosed. According to one embodiment, the battery protection circuit includes a battery voltage detection circuit configured to detect a battery voltage, output an effective trigger signal if the battery voltage reaches a voltage protection threshold, and output an ineffective trigger signal otherwise; a delay circuit configured to receive the trigger signal, output an effective status signal if the trigger signal is maintained effective continuously over a period of time, and outputs an ineffective status signal otherwise; a protection driver configured to receive the trigger signal and the status signal, enter a driving state when both the trigger signal and the status signal are effective, enter a non-driving state when both the trigger signal and the status signal are ineffective, and enter a ready driving state when the trigger signal is effective and the status signal is ineffective. | 10-21-2010 |
20100302822 | Flyback Power converters - Designs of flyback power converters are described. According to one aspect of the designs, a power converter includes a primary side including a primary winding of a transformer coupled to an input voltage and a primary switch for switching on or off the primary winding, a secondary side including a secondary winding of the transformer for generating an output voltage, and a loop controller configured to sample a feedback voltage representative of the output voltage, generate a gate signal with a fixed falling edge and an adjustable rising edge to drive the primary switch, and adjust a duty cycle of the gate signal by adjusting the rising edge of the gate signal until the feedback voltage converges to a reference voltage. | 12-02-2010 |
20110115308 | FEEDER AUTOMATION SYSTEM AND METHOD FOR OPERATING THE SAME - A feeder automation system and a method for operating the feeder automation system are disclosed. The feeder automation system comprises a first domain comprising a first slave station; a second domain comprising a second slave station; and a tie-switch provided between the first domain and the second domain. The first slave station is adapted to operate the tie-switch directly, and the second slave station is adapted to operate the tie-switch through the first slave station. When a fault occurs in the system, the first slave station and the second slave station cooperate with each other to perform fault detection, fault isolation, and fault restoration etc. without interacting with a master station. | 05-19-2011 |
20110316507 | Multiple-input comparator and power converter - Techniques pertaining to multiple-input comparator and power converter designs are disclosed. According to one aspect, the present invention discloses a multiple-input comparator comprising a pair of differential transistors connected by a resister. The gate terminals of the transistor pair serve as the input terminals of the comparator for receiving external voltage for comparison. The terminal of the resistor serves as the current input terminal and is either connected to a current source or a current sink. A power inverter utilizing the multiple-input comparator is also disclosed. The power inverter comprises a power switch driven by a PMW signal, a voltage sampling circuit, an error amplifier and a multiple-input PWM comparator. | 12-29-2011 |
20120089262 | INTELLIGENT PROCESS INTERFACE AND SUBSTATION AUTOMATION SYSTEM - This specification discloses an intelligent and digitalized process level interface which is referred to herein as an Intelligent Process Interface (IPI). The input of the IPI includes both analog and digital channels and therefore the IPI can be used for substations in transition or retrofit stages with both conventional and non-conventional primary devices. The IPI acts not only as a digitalized interface, but also as an intelligent supervisory and control unit for switching functions. The architecture of the IPI is flexible and allows for the functionality to be distributed to several devices. | 04-12-2012 |
20130132555 | COMMUNICATION METHOD AND APPARATUS OF NETWORK MANAGEMENT SYSTEM - The invention provides a communication system for a power distribution network, which comprises at least two distribution domains, each of the domains includes one management device and at least one electrical device. The management device is configured as connected with the electrical devices within its domain, and is further configured as capable of collect information from the electrical devices. The system also comprises a communication link, which is arranged for the management devices of different domains, and the management devices are configured as capable of directly exchanging information through the link. | 05-23-2013 |
20130148388 | AC-DC flyback converter and loop compensation method thereof - The prevent invention provides an AC-DC flyback converter and a loop compensation method thereof. The AD-DC flyback converter comprises an isolating transformer, a power switch, and a feed control module. The feed control module includes a compensating circuit, a voltage buffer, and an error amplifier having a first resistor and a second resistor, and a pulse width modulation controller. With the AC-DC flyback converter and the loop compensating method, the system stability can be improved and the loop bandwidth can be reduced. | 06-13-2013 |
20140358225 | POSTERIOR CHAMBER INTRAOCULAR LENS - The present invention relates to a posterior chamber intraocular lens (IOL), comprising: an optic consisting of an effective optical area and an effective optical area edge; at least two haptics connected to the optic, wherein a posterior surface of the effective optical area is a convex surface, and a basic spherical surface thereof has a radius of curvature in a range of 6.6 mm-80.0 mm. The effective optical area of the posterior chamber IOL adopts a design with the posterior surface obviously convex, which reduces the distance between the posterior surface of the effective optical area of the IOL and the posterior capsule, improves the stability of a spatial position of the IOL in a capsule bag, and reduces an incidence rate of posterior capsule opacification (PCO) after implantation of the IOL; since the effective optical area anterior surface is relatively flat, the IOL haptics will not be tightly pressed on the effective optical area anterior surface upon folding, the haptics are more easily unfolded after implantation into the eye and the support haptics are not mutually adhered to the effective optical area, and meanwhile the IOL imaging quality can be improved and/or the visual quality of the astigmatism sufferer is enhanced. | 12-04-2014 |