Cirrus Logic Inc.

Silicon Laboratories Inc.

Arnab Dutta

John L Melanson

Ramin Zanbaghi

Rahul Singh

Prashanth Drakshapalli

Thirumalai Rengachari

Eric Jerome King

Siddharth Maru

Stephen Timothy Hodapp

Firas Azrai

Nicholas Montgomery Atkinson

Essam S Atalla

Erik Pankratz

A POR circuit for a secondary supply domain of an IC. A bias and reference circuit provides startup current and a reference voltage for a comparator. The comparator compares the reference voltage with a primary supply voltage and develops a bias current. The bias and reference circuit and the comparator includes a VGS loop which mirrors the bias current to develop the reference voltage. When the comparator switches, the bias current is at the low quiescent current level. A level shift and isolation circuit initially isolates a primary POR signal from the secondary domain. When the comparator switches, the primary POR signal is detected and level shifted to control the reset state. The delay circuit senses ramping of the secondary supply voltage and provides a delayed secondary POR signal a predetermined time period after the secondary supply voltage achieves a predetermined voltage threshold to additionally control the reset state.

Power-on reset system for secondary supply domain

An apparatus includes an integrated circuit (IC), which includes complementary metal oxide semiconductor (CMOS) circuitry that includes a pull-up network coupled to a supply voltage and at least one input signal. The IC further includes a first metal oxide semiconductor (MOS) transistor coupled to the pull-up network and to a first bias voltage to reduce a gate-induced drain leakage (GIDL) current of the CMOS circuitry.

Apparatus with electronic circuitry having reduced leakage current and associated methods

A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as a converter in LED-based light bulbs. The power stage may be operated by a controller to maintain a desired current output to the LED load. The controller may operate the power stage by monitoring a start and end of a reverse recovery time of the BJT. Information regarding the start and end of the reverse recovery time may be used in the control of the power stage to improve efficiency of the power stage.

Switch-mode drive sensing of reverse recovery in bipolar junction transistor (BJT)-based power converters

Multiple measurements may be obtained via a single pin of an integrated circuit (IC) to set multiple control parameters of a light emitting diode (LED) controller within the IC. For example, a first input signal may be applied from the IC to two or more components via a single IC pin. A first output signal may be obtained from the two or more components via the single IC pin. A second input signal may be applied from the IC to the two or more components via the single IC pin, and a second output signal may be obtained from the two or more components via the single IC pin. A first parameter and a second parameter of the two or more components may be calculated based, at least in part, on the first output signal and the second output signal obtained via the single IC pin.

Measurements of multiple external components through a single pin of an integrated circuit

A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as for LED-based light bulbs. The BJT may be switched on and off from a controller coupled to two terminals of the BJT. Through the two terminals, the control IC may dynamically adjust a reverse recovery time period of the BJT. The reverse recovery time period may be adjusted by changing an amount of base charge that accumulates on the BJT. Additional, the reverse recovery may be controlled through the use of a reverse base current source applied to the BJT after beginning switching off the BJT.

Two terminal drive of bipolar junction transistor (BJT) of a light emitting diode (LED)-based bulb

A self-oscillating resonator (SOR) may be used to control current through light emitting diodes (LEDs). The SOR may be started and stopped by a controller coupled to a transistor switch in the SOR. The controller may output a control signal that starts and stops the SOR by coupling a supply voltage or a ground to a base of the transistor switch in the SOR. Additional control over the current output to the LEDs may be gained through a resistive DAC coupled to the SOR and duty cycling the SOR.

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Austin, TX, United States of America

Arnab Dutta