Abstract: A PWM control circuit for a voltage regulator including a compensation network, a ramp generator providing a ramp voltage, an offset adjust circuit and a comparator circuit. The compensation network senses the output voltage, receives a reference voltage, and outputs a compensation voltage. The offset adjust circuit adjusts a selected one of the ramp voltage and the compensation voltage based on the reference voltage. The comparator circuit compares the compensation voltage with the ramp voltage and provides a PWM signal for controlling the output voltage. The offset adjust circuit may generate an offset voltage based on the reference voltage and a gain G of the voltage regulator. The offset adjust circuit may subtract the offset voltage from either the ramp voltage or the compensation voltage to provide an adjusted voltage to the comparator circuit.

Abstract: The present disclosed integrated circuit includes a substrate having a top surface, a buried N type layer in the substrate, N type contact region extending from the surface to the buried N type region, a buried P type region abutting and above the buried N type region in the substrate, a P type contact region extending from the surface to the buried P type region, and an N type device region in the surface and above the buried P type region. The P type impurity of the buried P type region including an impurity of a lower coefficient of diffusion than the coefficient of diffusion of the impurities of the P type contact region.

Abstract: This disclosure describes an improved process and resulting structure that allows a single masking step to be used to define both the body and the threshold adjustment layer of the body. The method consists of forming a first mask on a surface of a substrate with an opening exposing a first region of the substrate; implanting through the opening a first impurity of a first conductivity type and having a first diffusion coefficient; and implanting through the opening a second impurity of the first conductivity type and having a second diffusion coefficient lower than the first diffusion coefficient. The first and second impurities are then co-diffused to form a body region of a field effect transistor. The remainder of the device is formed.

Abstract: A voltage converter including a buck converter and a capacitive voltage divider. The converter includes four capacitors, a switch circuit, an inductor and a controller. A first capacitor is coupled between a reference node and a first output node which develops a first output voltage. A second capacitor is coupled between an input node and either the reference node or the first output node. The switch circuit couples a third capacitor between the reference and first output nodes in a first state of a PWM signal, and couples the third capacitor between the first output and input nodes in a second PWM signal state. The inductor is coupled to the third capacitor and provides a second output node coupled to the fourth capacitor providing a second output voltage. The controller controls the duty cycle of the PWM signal to regulate the second output voltage to a predetermined level.

Abstract: A voltage converter including a capacitive voltage divider combined with a buck converter and battery charger. The converter includes four capacitors, a switch circuit, an inductor and a controller. The capacitors form a capacitor loop between an input node and a reference node and include a fly capacitor controlled by the switch circuit, which is controlled by a PWM signal to half the input voltage to provide a first output voltage on a first output node, and to convert the first output voltage to the second output voltage via the inductor. The controller controls the PWM signal to regulate the second output voltage, and provides a voltage control signal to control the input voltage to maintain the first output node between a predetermined minimum and maximum battery voltage levels. A battery charge path is coupled to the reference node and battery charge mode depends upon the battery voltage.

Abstract: A method of a fabricating a multiple wavelength adapted photodiode and resulting photodiode includes the steps of providing a substrate having a first semiconductor type surface region on at least a portion thereof, implanting and forming a second semiconductor type shallow surface layer into the surface region, and forming a multi-layer anti-reflective coating (ARC) on the shallow surface layer. The forming step includes depositing or forming a thin oxide layer on the shallow surface layer and depositing a second dielectric layer different from the thin oxide layer on the thin oxide layer. An etch stop is formed on the second dielectric, wherein the etch stop includes at least one layer resistant to oxide etch. At least one oxide including layer (e.g. ILD) is then deposited on the etch stop. The oxide including layer and etch stop are then removed to expose at least a portion of the ARC to the ambient.

Abstract: A method of operating a synchronous power converter generates a control signal in a load current compensation circuit based on a light load condition at the converter, where the control signal controls a gate driver for at least one power switch of the converter. When the gate driver is turned off via the control signal, the method monitors one or more comparison signals in a reference voltage adjustment module of the compensation circuit, a first comparison signal of the one or more comparison signals indicative of a voltage level at a phase node of the converter. Based on a remaining body diode conduction level associated a body diode with the at least one power switch as detected by at least a second comparison signal, the method adjusts a reference voltage for the at least one power switch with the adjustment module until the body diode is no longer conducting.

Abstract: A method of operating a synchronous power converter detects when at least one of an upper power switch and a lower power switch of the converter transition to an off state during a dead-time transition interval between the upper power switch and the lower power switch. The method generates a first comparison signal, indicative of a voltage level at a phase node of the converter, in a dead-time adjustment circuit coupled to the converter. The method further detects a body diode conduction level of at least one of the upper and lower power switches in the off state using at least a second comparison signal generated in the dead-time adjustment circuit and adjusts the dead-time transition interval between the upper power switch and the lower power switch using at least one current source from the dead-time adjustment circuit to reduce the dead-time transition interval to a desired dead-time interval.

Abstract: A method of providing threshold voltage monitoring and control in synchronous power converters is disclosed. The method establishes a threshold voltage level for at least one of an upper gate and a lower gate power switch in a synchronous power converter. The threshold voltage levels indicate switching delay times are present in the upper and lower gate power switches. The method detects body diode conduction levels for both the upper and lower gate power switches. When at least one of the detected body diode conduction levels exceed a prescribed body diode conduction level, the method adjusts the threshold voltage level for at least one of the upper and lower gate power switches to reduce a body diode conduction time for the at least one of the upper and lower gate power switches.

Abstract: A MOSFET-based, multi signal-switching circuit controllably passes analog/audio signals and digital signals through a common terminal to a single connector. Analog/audio signals are coupled through a single N-channel MOSFET analog signal switch which, when turned-ON, minimizes distortion of the analog/audio signal and capacitive loading to an adjacent, MOS-based or CMOS-based digital data signal switch. A respective turn-OFF circuit maintains its associated switch MOSFET turned OFF.

Abstract: An electrostatic discharge (ESD) device and method is provided. The ESD device can comprise a substrate doped to a first conductivity type, an epitaxial region doped to the second conductivity type, and a first well doped to the first conductivity type disposed in the substrate. The first well can comprise a first region doped to the first conductivity type, a second region doped to a second conductivity type, and a first isolation region disposed between the first region and the second region. The ESD device can also comprise a second well doped to a second conductivity type disposed in the substrate adjacent to the first well, where the second well can comprise a third region doped to the first conductivity type, a fourth region doped to the second conductivity type, and a second isolation region disposed between the third region and the fourth region.

Abstract: A system and method is provided for improving the accuracy of the voltage reference output of a floating gate voltage reference circuit by minimizing the temperature coefficient, Tc. The system and method provides a minimized Tc on output reference voltage, for a wide variety of such output voltages. In a dual floating gate voltage reference circuit wherein a voltage reference output (Vref) is generated as a function of the difference in charge of said floating gates, a method includes causing each of the floating gates to change voltage substantially the same amount as a function of temperature such that, during a read mode of the reference circuit, the temperature coefficient, Tc, of the voltage reference output is substantially reduced. The system and method achieves very low Tc over a wide range of reference or comparator voltages using low cost analog test equipment and methods.

Abstract: A steady state frequency control circuit for a variable frequency regulator including an open loop frequency control circuit, a frequency detector and a comparator circuit. The variable frequency regulator provides a clock signal indicating actual operating frequency and has a frequency control parameter for adjusting steady state operating frequency. The frequency detector receives the clock signal and provides a frequency sense signal which is compared with a steady state frequency reference signal to provide a frequency adjust signal. The frequency control parameter is adjusted by the frequency adjust signal to control steady state frequency.

Abstract: A battery charger comprises charging circuitry for providing a battery charging voltage responsive to an input voltage. First circuitry provides both over-voltage protection and an input voltage bypass signal responsive to the input voltage. The first circuitry includes a low impedance switch having a resistance of at least 500 m? for connecting the input voltage to an output voltage node. The first circuit also includes a higher impedance switch having a resistance of at least 1000 m? for providing the input voltage as a voltage bypass signal.

Abstract: In accordance with the invention, there are various methods of making an integrated circuit comprising a bipolar transistor. According to an embodiment of the invention, the bipolar transistor can comprise a substrate, a collector comprising a plurality of alternating doped regions, wherein the plurality of alternating doped regions alternate in a lateral direction from a net first conductivity to a net second conductivity, and a collector contact in electrical contact with the collector. The bipolar transistor can also comprise a heavily doped buried layer below the collector, a base in electrical contact with a base contact, wherein the base is doped to a net second conductivity type and wherein the base spans a portion of the plurality of alternating doped regions, and an emitter disposed within the base, the emitter doped to a net first conductivity, wherein a portion of the alternating doped region under the emitter is doped to a concentration of less than about 3×1012 cm?2.

Abstract: A system and method for determining an initial duty cycle for startup of a voltage regulator involves generating a first current source responsive to an input voltage to the voltage regulator and generating a second current source responsive to an output voltage of the voltage regulator. A first capacitor is charged using the first current source responsive to a duty cycle of a PWM signal of the voltage regulator to a first voltage. A second capacitor is charged to a second voltage responsive to a period of the PWM signal of the voltage regulator. The initial duty cycle for startup of the voltage regulator is established as the duty cycle of the PWM signal when the first voltage is substantially equal to the second voltage.

Abstract: A modulator control circuit including a linear control circuit, a non-linear control circuit, and a combiner. The linear control circuit has an input receiving a compensation signal indicative of an output parameter and an output providing a first control signal. The non-linear control circuit has an input receiving the compensation signal and an output providing a second control signal. The non-linear control circuit senses transients of the compensation signal not otherwise detected by the linear control circuit and asserts the second control signal indicative thereof. The combiner combines the first and second control signals to provide a pulse width modulation signal for controlling the output parameter, such as output voltage or the like.

Abstract: In a phase-locked loop (PLL), a phase detector receives a reference signal and a feedback oscillator signal, generates a phase-detect pulse having a first duration in response to one of the reference and feedback signals, and generates a phase-correction pulse having second, shorter duration in response to the phase-detect pulse. By shortening the phase-correction pulse, such a phase detector can reduce or eliminate the overcorrection period during which the phase-correction pulse is active after phase correction is achieved, and thus can reduce or eliminate the phase error that the overcorrection period may introduce into a PLL's oscillator signal.

Abstract: An integrated circuit includes a first and second diode connected in parallel. The first diode has a first breakdown voltage and has first P type region and first N type region adjacent to each other at the surface of the substrate of a substrate to form a lateral diode. The second diode has a second breakdown voltage less than the first breakdown voltage and has a second P type region and second N type region lateral adjacent to each other in the substrate to form a lateral diode below the surface The first and second N type regions overlap and the first and second P type region being electrically connected whereby the first and second diodes are in parallel.

Abstract: An embodiment of a coupled-inductor core includes first and second members and first and second forms extending between the first and second members. The first form has a parameter (e.g., length) of a first value, and is operable to conduct a first magnetic flux having a first density that depends on the first value of the parameter. The second form is spaced apart from the first form, has the parameter (e.g., length) of a second value different from the first value, and is operable to conduct a second magnetic flux having a second density that depends on the second value of the parameter. Because two or more of the forms of such a core may have different values for the same parameter, the core may be suitable for use in a multiphase power supply where the currents through the phases are unbalanced.