Abstract: In a general aspect, an apparatus can include an insulated-gate bipolar transistor device (IGBT), a gate driver circuit (driver) coupled with a gate terminal of the IGBT and a low-resistance switch device coupled between an emitter terminal of the IGBT and an electrical ground terminal, the low-resistance switch device being coupled with the electrical ground terminal via a resistor. The apparatus can also include a current sensing circuit coupled with the driver and a current sense signal line coupled with the current sensing circuit and a current sense node, the current sense node being disposed between the low-resistance switch device and the resistor. The apparatus can further include a control circuit configured, when the driver is off, to detect, based on a voltage on the current sense node, when a current through the resistor is above a threshold value and disable the IGBT in response to the detection.
Abstract: A synchronous rectifier driver pre-positions a gate of a synchronous rectifier to allow for fast turn-off. The synchronous rectifier driver turns ON the synchronous rectifier by driving the gate at a high level for a period of time that is based on a previous conduction time of the synchronous rectifier. The synchronous rectifier driver thereafter drives the gate at a lower level that is sufficient to keep the synchronous rectifier ON. The synchronous rectifier can be quickly turned OFF by further reducing the level of the drive signal at the gate of the synchronous rectifier.
Abstract: In at least one general aspect, a SiC device can include a drift region of a first conductivity type, a shielding body, and a Schottky region. The SiC device can include a rim having a second conductivity type at least partially surrounding the shielding body and the Schottky region. The SiC device can include a termination region at least partially surrounding the rim and having a doping of the second conductivity type. The termination region can have a transition zone disposed between a first zone and a second zone where the first zone has a top surface lower in depth than a depth of a top surface of the second zone and the transition zone has a recess.
Abstract: In one general aspect, an apparatus can include a junction-less, gate-controlled voltage clamp device having a gate terminal coupled to a voltage reference device.
Abstract: In a general aspect, an apparatus can include a temperature measurement circuit configured to produce a first signal indicating a first operating temperature of a first semiconductor device and a temperature comparison circuit operationally coupled with the temperature measurement circuit. The temperature comparison circuit can be configured to compare the first signal with a second signal indicating a second operating temperature of at least a second semiconductor device and produce a comparison signal indicating whether the indicated first operating temperature is higher, lower or equal to the indicated second operating temperature. The apparatus can also include an adjustment circuit configured to adjust operation of the first semiconductor device based on the comparison signal.
Abstract: In some general aspects, an apparatus may include a first semiconductor die, a second semiconductor die, and a capacitive isolation circuit being coupled to the first semiconductor die and the second semiconductor die. The capacitive isolation circuit may be disposed outside of the first semiconductor die and the second semiconductor die. The first semiconductor die, the second semiconductor die, and the capacitive circuit may be included in a molding of a semiconductor package.
Type:
Grant
Filed:
January 9, 2015
Date of Patent:
August 15, 2017
Assignee:
Fairchild Semiconductor Corporation
Inventors:
John Constantino, Timwah Luk, Ahmad Ashrafzadeh, Robert L. Krause, Etan Shacham, Maria Clemens Ypil Quinones, Janusz Bryzek, Chung-Lin Wu
Abstract: In one general aspect, a method can include calculating, at a calibration temperature of a speaker, a calibration parameter through a coil of the speaker in response to a first test signal, and can include sending a second test signal through the coil of the speaker. The method can also include measuring a parameter through the coil of the speaker based on the second test signal, and calculating a temperature change of the coil of the speaker based on the parameter and based on the calibration parameter at the calibration temperature.
Type:
Grant
Filed:
November 7, 2013
Date of Patent:
August 8, 2017
Assignee:
Fairchild Semiconductor Corporation
Inventors:
Philip Crawley, William D. Llewellyn, Majid Shushtarian
Abstract: A flyback converter includes a primary-side switch that controls conduction of current on a primary side of a transformer and a synchronous rectifier on a secondary side of the transformer. A synchronous rectifier driver controls the conduction of the synchronous rectifier by adaptively adjusting a turn-off threshold of the synchronous rectifier.
Type:
Application
Filed:
November 22, 2016
Publication date:
August 3, 2017
Applicant:
FAIRCHILD SEMICONDUCTOR CORPORATION
Inventors:
Hangseok CHOI, Lei CHEN, Cheng-Sung CHEN
Abstract: Generally, this disclosure provides circuitry and methods for determining the output capacitance of an output load capacitor of a power supply. The output capacitance is generally determined by beginning a calibration period and charging an output capacitor with a current source to generate an output voltage. The output voltage may be compared to a reference voltage, and a time period is determined during which the output voltage is less than the reference voltage. The capacitance value, C, of the output capacitor may be determined based on, at least in part, the determined time period. This disclosure also provides circuitry and methods to adjust certain parameters of the power supply based on the determined C value. For example, in a ramp compensation portion of the power supply, the value of a ramp capacitor and/or reset resistor may be adjusted once the value of C is determined.
Abstract: A switching converter includes a synchronous rectifier and a synchronous rectifier driver that controls conduction of the synchronous rectifier. The synchronous rectifier driver turns OFF the synchronous rectifier in response to a turn-off trigger. The synchronous rectifier driver prevents the turn-off trigger from turning OFF the synchronous rectifier during a turn-off trigger blanking time that is adaptively set based on a conduction time of the synchronous rectifier.
Type:
Application
Filed:
November 22, 2016
Publication date:
August 3, 2017
Applicant:
FAIRCHILD SEMICONDUCTOR CORPORATION
Inventors:
Hangseok CHOI, Lei CHEN, Cheng-Sung CHEN
Abstract: This document discusses, among other things, systems and methods to reduce power use of an accessory detection device. The accessory detection device can be configured to be coupled to a mobile device having an audio jack configured to be coupled to a mobile device accessory having a send/end key. In an example, the accessory detection device can include a comparator and a switch. The comparator can be configured to receive mobile device accessory information from the mobile device accessory and to determine activation of the send/end key using the received mobile device accessory information. The switch can be configured to receive connection information indicative of mobile device accessory connection to the audio jack and to isolate a reference input of the comparator from a supply voltage using the connection information, for example, to reduce leakage current.
Abstract: In one general aspect, an apparatus can include a load terminal, and a power source terminal. The apparatus can include a current limiter coupled to the load terminal and coupled to the power terminal. The current limiter can be configured to limit a current from the power source terminal to the load terminal using an electric field activated in response to a difference in voltage between the power source terminal and the load terminal.
Abstract: In a general aspect, a wireless multichip module can include a leadframe structure with portions configured to receive at least one flip-chip mounted semiconductor die, including one or more of an integrated circuit, a high side MOSFET and/or a low side MOSFET, which can form a half-bridge circuit that is encapsulated in a molding compound. The module can be assembled without any bond wires (e.g., be wireless). The module may include carry passive components including an external input capacitor and/or an internal input capacitor.
Abstract: An integrated power stage device includes a switch node that is coupled to an output inductor. The integrated power stage device generates a monitor current that is a scaled version of the current through the output inductor. The integrated power stage device outputs a single-ended offset monitor current that is equal to the monitor current plus a DC offset current. A PWM controller senses the current through the output inductor by receiving a monitor voltage that is developed from the offset monitor current. The PWM controller generates a PWM signal in accordance with the sensed output inductor current to control a switching operation of a power switch of the integrated power stage device.
Abstract: In one general aspect, an apparatus can include a silicon carbide (SiC) device can include a gate dielectric, a first doped region having a first conductivity type, a body region of the first conductivity type, and a second doped region having a second conductivity type. The second doped region has a first portion disposed between the first doped region and the body region, and the second doped region has a second portion disposed between the first doped region and the gate dielectric.
Abstract: In a general aspect, a packaged semiconductor device can include a semiconductor die having at least a first terminal on a first side of the semiconductor die and a second terminal on a second side of the semiconductor die. The device can include a leadframe portion electrically coupled to the first terminal of the semiconductor die and a clip portion electrically coupled to the second terminal of the semiconductor die. The device can include a molding compound. A surface of the leadframe portion and a first surface of the molding compound can define at least a portion of a first surface of the device. A surface of the clip portion and a second surface of the molding compound can define at least a portion of a second surface of the device that is parallel to the first surface of the device.
Type:
Grant
Filed:
March 28, 2016
Date of Patent:
June 20, 2017
Assignee:
Fairchild Semiconductor Corporation
Inventors:
Margie Rios, Aira Lourdes Villamor, Maria Cristina Estacio, Armand Vincent Jereza
Abstract: In one general aspect, an apparatus can include a semiconductor substrate, and a trench defined within the semiconductor substrate and having a depth aligned along a vertical axis, a length aligned along a longitudinal axis, and a width aligned along a horizontal axis. The apparatus includes a dielectric disposed within the trench, and an electrode disposed within the dielectric and insulated from the semiconductor substrate by the dielectric. The semiconductor substrate can have a portion aligned vertically and adjacent the trench, and the portion of the semiconductor substrate can have a conductivity type that is continuous along an entirety of the depth of the trench. The apparatus is biased to a normally-on state.
Type:
Grant
Filed:
August 7, 2014
Date of Patent:
June 13, 2017
Assignee:
Fairchild Semiconductor Corporation
Inventors:
Tirthajyoti Sarkar, Adrian Mikolajczak, Ihsiu Ho, Ashok Challa
Abstract: The present disclosure describes full bridge power supply systems and control methods. In at least one embodiment, the full bridge power supply system may be driven utilizing a two-phase continuous conduction switching mode to control the inductor current. In another embodiment, the full bridge power supply system may be driven utilizing variably-configured three-phase continuous conduction modes to control the inductor current when an input voltage is within a window value to the output voltage. In another embodiment, the full bridge power supply may be driven using a four-phase discontinuous conduction switching mode to control the inductor current when a load current is below a current lower threshold.
Abstract: This document discusses, among other things, a charge regulator configured to optimize charging of an energy storage device by measuring an internal voltage drop of the energy storage device using an open circuit voltage (OCV) across the terminals of the energy storage device during charging and a voltage across the terminals of the energy storage device during charging (CCV).