Other

Altoran Chips & Systems

Altoran Chip and Systems, Inc.

Mosys, Inc.

Jae Hong Jeong

Minjong Kim

Kyeongtae Moon

Weifeng Chen

Juhwan Jeong

Jeong Yeol Choi

Jungung Kim

Gyehyun Cho

Jongho Kim

A light emitting diode (LED) light engine includes: an LED; an LED driver for driving the LED; a bottom printed circuit board (PCB), the LED and the LED driver being securely mounted to the bottom PCB; and a top PCB secured to the bottom PCB, the top PCB including first and second cavities for receiving the LED and the LED driver therein. The LED light engine further includes a layer potted over the LED and formed of material containing a phosphor, or a plate that is disposed over the LED and secured to the top PCB and includes a layer formed of material containing a phosphor. The phosphor is excited by the light emitted from the LEDs to the intensity distribution over the wavelength of the light emitted by the LED.

Light emitting diode light engine

An AC light system with a control unit for controlling power of an LED is disclosed. According to one embodiment, a driver circuit for driving LEDs has a plurality of current sinks, a first interface configured to receive an AC power from an AC power source, a second interface to a plurality LED groups. The driver circuit further has a third interface configured to receive a control input from a control unit. Each current sink of the plurality of current sinks controls an LED current flowing through a corresponding LED group based on the control input from the control unit.

AC lighting system with a control unit for controlling power of an LED

An AC direct driver lighting system is disclosed. According to one embodiment, the AC direct driver lighting system includes a plurality of LED groups serially connected to an AC power source, and an AC driver comprising a plurality of current sinks. Each of the plurality of current sinks is connected between a respective LED group of the plurality of LED groups and a ground. The AC direct driver lighting system further includes a valley fill circuit coupled to a target LED group of the plurality of LED groups. The valley fill circuit charges from the AC power source and supplies electrical power to the target LED group via a current path established between the AC power source and the ground via at least one of the plurality of current sinks.

Balanced AC direct driver lighting system with a valley fill circuit and a light balancer

An AC direct driver lighting system including a surge protection circuit and a current limiting circuit is disclosed. According to one embodiment, the AC direct driver lighting system includes an LED load, a rectifier, and an LED driver configured to receive rectified AC voltage from an AC power source and drive the LED load. The AC direct driver lighting system further includes a surge protection circuit and a current limiting circuit disposed between the AC power source and the LED load. The surge protection circuit and the current limiting circuit suppress excessive current flowing through the AC direct driver lighting system.

System and method for providing surge protection for an AC direct step driver lighting system

An AC lighting system for providing uniform light distribution is disclosed. According to one embodiment, the AC lighting system includes an AC driver and LED packages electrically connected to the AC driver. Each LED package includes a plurality of LED elements and is physically distributed over an illuminating surface of the AC lighting system. The AC driver has a first current sink that drives a first LED group and a second current sink that drives the first LED group and a second LED group. The first LED group includes at least one LED element from each of the LED packages, and the second LED group includes at least one LED element other that the first set of LED elements from each of the LED packages.

AC direct drive lighting system for providing uniform light distribution

A driver circuit for driving light emitting diodes (LEDs). The driver circuit includes: a string of LEDs divided into n groups, the n groups of LEDs being electrically connected to each other in series, a downstream end of group m&#x2212;1 being electrically connected to the upstream end of group m, where m is a positive number equal to or less than n. The driver circuit also includes a power source coupled to an upstream end of group 1 and operative to provide an input voltage and a plurality of current regulating circuits, each of the current regulating circuits being coupled to the downstream end of a corresponding group at one end and coupled to a ground at the other end and including a sensor amplifier and a cascode having first and second transistors.

Light emitting diode driver having cascode structure

A driver circuit for driving light emitting diodes (LEDs). The driver circuit includes a string of LEDs divided into n groups, the n groups of LEDs being electrically connected to each other in series, a downstream end of group m&#x2212;1 being electrically connected to the upstream end of group m. The driver circuit also includes a power source coupled to an upstream end of group. The driver circuit further includes a plurality of current regulating circuits, where each current regulating circuit is coupled to the downstream end of a corresponding group at one end and coupled to a ground at another end and includes a sensor amplifier and a cascode having two transistors. The driver circuit also includes a phase control logic for sending a signal to each of the current regulating circuits to thereby control a current flow through each of the current regulating circuits.

Light emitting diode driver having phase control mechanism

A driver circuit for driving light emitting diodes (LEDs). The driver circuit includes: a string of LEDs divided into n groups, the n groups of LEDs being electrically connected to each other in series, a downstream end of group m&#x2212;1 being electrically connected to the upstream end of group m, where m is a positive number equal to or less than n. The driver circuit also includes a plurality of current regulating circuits, each of the current regulating circuits being coupled to the downstream end of a corresponding group at one end and coupled to the ground at the other end and including a sensor amplifier and a cascode having first and second transistors, each sensor amplifier being coupled to a different voltage source for providing a different reference voltage thereto.

Light emitting diode driver

A driver circuit for driving light emitting diodes (LEDs). The driver circuit includes a string of LEDs divided into n groups and the n groups of LEDs is electrically connected to each other in series, where a downstream end of group m&#x2212;1 is electrically connected to the upstream end of group m. The driver circuit also includes a power source coupled to an upstream end of group 1 and provides an input voltage. The driver circuit further includes current regulating circuits, where each of the current regulating circuits is coupled to the downstream end of the corresponding group at one end and coupled to a ground at the other end. Each of the current regulating circuits includes a sensor amplifier and a cascode having first and second transistors. The driver circuit also includes detectors, where each of the detectors detects a source voltage of the first transistor.

A driver circuit for driving light emitting diodes (LEDs). The driver circuit includes: a string of LEDs divided into n groups, the n groups of LEDs being electrically connected to each other in series, a downstream end of group m-being electrically connected to the upstream end of group m, where m is a positive number equal to or less than n. The driver circuit also includes a plurality of current regulating circuits, each of the current regulating circuits being coupled to the downstream end of a corresponding group at one end and coupled to the ground at the other end and including a sensor amplifier and a cascode having first and second transistors, each sensor amplifier being coupled to a different voltage source for providing a different reference voltage thereto.

A driver circuit for driving light emitting diodes (LEDs). The driver circuit includes a string of LEDs divided into n groups and the n groups of LEDs is electrically connected to each other in series, where a downstream end of group m&#x2212;1 is electrically connected to the upstream end of group m. The driver circuit also includes a power source coupled to an upstream end of groupand provides an input voltage. The driver circuit further includes current regulating circuits, where each of the current regulating circuits is coupled to the downstream end of the corresponding group at one end and coupled to a ground at the other end. Each of the current regulating circuits includes a sensor amplifier and a cascode having first and second transistors. The driver circuit also includes detectors, where each of the detectors detects a source voltage of the first transistor.

A driver circuit for driving light emitting diodes (LEDs). The driver circuit for driving light emitting diodes (LEDs) includes a string of LEDs divided into n groups. The n groups of LEDs are electrically connected to each other in series and the downstream end of group m&#x2212;1 is electrically connected to the upstream end of group m, where m is a positive number equal to or less than n. The driver circuit also includes a plurality of current regulating circuits, where each of the current regulating circuits is coupled to a downstream end of a corresponding group and has at least one transistor and a detector for measuring a current flowing through the corresponding group.

Light emitting diode driver using turn-on voltage of light emitting diode

An embedded memory system that includes DRAM cells and logic transistors. The capacitor of the embedded memory responds to a positive bias voltage of &#xbd; Vdd. The wordline driver of a p-channel access transistor applying the positive power supply voltage when the p-channel access FET is not being accessed and a voltage lower than the threshold voltage of the p-channel access FET is being accessed. For DRAM cells containing an n-channel access FET, the wordline driver applies either a negative voltage or the ground voltage to the n-channel access FET when the DRAM cell is not being accessed. A second voltage composed of Vdd and a boosted voltage is applied to the n-channel FET when the DRAM cell is being accessed.

Growing community of inventors

Saratoga, CA, United States of America

Jae Hong Jeong