Richtek Technology Corporation | Date: 2015-04-18
The present invention discloses a single-wire transmission method, which includes: providing a transmission signal including alternating high and low levels through a single-wire, wherein a period of one of the high and low levels defining a reference time and a period of the other of the high and low levels defining a content time; determining a relative relationship between the reference time and the content time; when the content time is smaller than a proportion of the reference time, defining the content time to express a first meaning; and when the content time is larger than the proportion of the reference time, defining the content time to express a second meaning.
Richtek Technology Corporation | Date: 2015-06-02
The present invention discloses a transient voltage suppression (TVS) device and a manufacturing method thereof. The TVS device limits a voltage drop between two terminals thereof not to exceed a clamp voltage. The TVS device is formed in a stack substrate including a semiconductor substrate, a P-type first epitaxial layer, and a second epitaxial layer stacked in sequence. In the TVS device, a first PN diode is connected to a Zener diode in series, wherein the series circuit is surrounded by a first shallow trench isolation (STI) region; and a second PN diode is connected in parallel to the series circuit, wherein the second PN diode is surrounded by a second STI region. The first STI region and the second STI region both extend from an upper surface to the second epitaxial layer, but not to the first epitaxial layer.
Richtek Technology Corporation | Date: 2015-01-13
The present invention discloses a light emitting device driver chip for driving light emitting devices in series. The chip includes: plural pins electrically connected to corresponding light emitting devices, respectively, wherein an internal voltage is provided through a predetermined one of the pins; a voltage regulation circuit for providing an operation voltage according to the internal voltage; a switch circuit including plural switch groups electrically connected to corresponding pins, respectively; a current source circuit for providing a current to the light emitting devices; and a switch control circuit for controlling the switch groups to determine which light emitting device is turned ON. The light emitting device driver chip does not directly receive the rectified input voltage.
Richtek Technology Corporation | Date: 2015-01-08
The present invention discloses a high voltage device and a manufacturing method thereof. The high voltage device includes: a substrate, having an isolation structure for defining a device region; a drift region located in the device region, wherein from top view, the drift region includes multiple sub-regions separated from one another but are electrically connected with one another; a source and a drain in the device region; and a gate on the surface of the substrate and between the source and drain in the device region.
Richtek Technology Corporation | Date: 2015-12-11
The present invention discloses a semiconductor composite film with a heterojunction and a manufacturing method thereof. The semiconductor composite film includes: a semiconductor substrate; and a semiconductor epitaxial layer, which is formed on the semiconductor substrate, and it has a first surface and a second surface opposite to each other, wherein the heterojunction is formed between the first surface and the semiconductor substrate, and wherein the semiconductor epitaxial layer further includes at least one recess, which is formed by etching the semiconductor epitaxial layer from the second surface toward the first surface. The recess is for mitigating a strain in the semiconductor composite film.