Avago Technologies Ecbu IP (singapore) Pte. Ltd.

Avago Technologies General IP (singapore) Pte. Ltd.

Avago Technologies International Sales Pte. Limited

Avago Technologies Ecbu IP Pte. Ltd.

Kah Weng Lee

Bin Zhang

Fun Kok Chow

Gek Yong Ng

Dominique Ho

Kwee Chong Chang

Kok Keong Richard Lum

Brian J Misek

Various embodiments of a light source driver are disclosed. In one embodiment, the light source driver may have a driving transistor coupled directly to at least one light source without having additional switches such that the light source driver may be operated with a low voltage supply. Optionally, the light source drivers may have a bypassing circuit configured to reduce power consumption, and peaking current generator configured to speed up the turn on time of the at least one light source. At least some of the circuits, and block diagrams disclosed herein may be implemented using conventional CMOS design and manufacturing techniques and processes to provide, for example, at least one or more integrated circuits.

Light source driver

A capacitive isolation system, capacitive isolator, and method of operating the same are disclosed. The capacitive isolation system is described to include a first semiconductor die and a second semiconductor die each having capacitive elements established thereon and positioned in a face-to-face configuration. An isolation layer is provided between the first and second semiconductor die so as to establish an isolation boundary therebetween. Capacitive coupling is used to carry information across the isolation boundary.

Isolator with reduced susceptibility to parasitic coupling

According to one embodiment, there is provided a high voltage isolation dual capacitor communication system comprising communication drive and sense electrodes and corresponding first and second capacitors that are formed in two separate devices. The two devices are electrically connected in series to provide a single galvanically-isolated communication system that exhibits high breakdown voltage performance in combination with good signal coupling. The system effects communications between drive and receive circuits through the first and second capacitors, and in a preferred embodiment is capable of effecting relatively high-speed digital communications. The system may be formed in a small package using, by way of example, CMOS or other semiconductor fabrication and packaging processes.

High voltage isolation dual capacitor communication system

According to one embodiment, there is provided an optocoupler system configured to generate current signals having high, low and no amplitude portions in response to the receipt of logic high and low input signals. The varying amplitude portions of the current signals are used to drive other portions of the isolation circuitry, and result in reduced power consumption and dissipation, as well as reduced pulse width distortion.

Optocoupler system with reduced power consumption and pulse width distortion

According to one embodiment, there is provided a semiconductor digital communication device comprising communication drive and sense electrodes formed in a single plane, where the electrodes have relatively high sidewalls. The relatively high sidewalls permit low electrical field densities to be obtained in the sense and drive electrodes during operation, and further permit very high breakdown voltages to be obtained between the electrodes, and between the drive electrode and an underlying ground plane substrate. The device effects communications between drive and receive circuits through the drive and sense electrodes by capacitive means, and in a preferred embodiment is capable of effecting relatively high-speed digital communications. The device may be formed in a small package using, by way of example, CMOS or other semiconductor fabrication and packaging processes.

High voltage isolation semiconductor capacitor digital communication device and corresponding package

A light sensor having first and second photodetectors and a current mirror is disclosed. The first photodetector receives a light signal and generates a light current proportional to the light intensity received by the first photodetector and a dark current that is independent of the light intensity. The second photodetector is connected in series with the first photodetector at a first node. The second photodetector has a covering that prevents light from reaching the second photodetector. The second photodetector generates a current equal to the dark current. The first photodetector is connected to a power source and the second photodetector is connected to an output node. The current mirror is connected to the first node and the output node and generates an output current that is proportional to the light current through the output node when the output node is connected to an external circuit.

High linearity CMOS ambient light sensor

A power supply generates a supply voltage that varies from a first voltage level to a second voltage level. A first current source is coupled to the power supply and generates a current that varies due to channel-length modulation. A channel-length modulation (CLM) compensation mechanism is provided to reduce the current variation of the first current source by compensating the channel-length modulation (CLM) of the first current source.

Channel-length modulation (CLM) compensation method and apparatus

An optocoupler system includes a buffer, isolation, and a detector. The system includes a current transfer ratio (CTR) with a temperature coefficient. The buffer includes a light source that generates light that passes through the isolation. A detector receives light that passes through the isolation and generates an output signal based on the received light. A current transfer ratio (CTR) temperature coefficient compensation mechanism is provided that generates a base signal with a temperature coefficient that compensates the temperature coefficient of the CTR.

Current transfer ratio temperature coefficient compensation method and apparatus for an optocoupler

Current transfer ratio temperature coefficient compensation method and apparatus

In one embodiment, a method is provided for reducing output current oscillations of a driver provided with i) a current sensing circuit that senses excessive current draws of an output stage of the driver, and ii) a feedback control circuit that reduces the excessive current draws. In accordance with the method, an output of the current sensing circuit is coupled to an input of a common source amplifier with source degeneration. The output of the common source amplifier is coupled to a node between an input stage and an amplification stage of the driver. The common source amplifier is configured to be activated when the current sensing circuit senses an excessive current draw of the output stage, at which time the feedback control circuit is also activated. Related apparatus is also disclosed.

Methods and apparatus for reducing output current oscillations of a driver provided with circuitry that senses and responds to excessive current draws of an output stage of the driver

Growing community of inventors

Singapore, Singapore

Kah Weng Lee