Three-terminal self-feedback linear galvanostat and manufacturing method thereof

Abstract

The invention discloses a three-terminal self-feedback linear galvanostat and a manufacturing method thereof, aiming at solving the technical problems of high cost performance and LED driving reliability. The three-terminal self-feedback linear galvanostat consists of a field effect transistor, a resistor and an adjustable resistor, wherein the source end of the field effect transistor is connected with one end of the resistor; the gate end of the field effect transistor is connected to the other end of the resistor; and the adjustable resistor is connected with the resistor in parallel. The manufacturing method disclosed by the invention comprises the following steps of: preparation of an epitaxial layer, ion implantation and knot-pushing, ion implantation, chemical vapor deposition, polycrystalline deposition and etching, etching of contact holes as well as metal deposition and etching. Compared with the prior art, the three-terminal self-feedback linear galvanostat has the advantages that: constant current output is kept at the same time of increasing alternating current voltage, an LED is powered on without delaying after reaching an LED threshold voltage, the LED keeps brightat low voltage, the LED is protected from being affected by voltage surge, the brightness of the LED is kept constant under the wide-voltage range, the LED is protected in the high input voltage, andlow cost and output stability are achieved.

Description

technical field [0001] The invention relates to a semiconductor power device and a preparation method thereof, in particular to a driving device for LED lighting and a preparation method thereof. Background technique [0002] Because LED has the characteristics of long service life, no pollution, and low power consumption, it can meet the development needs of high-efficiency, mercury-free, diversified and artistic lighting in the world today. With the rapid update of LED research and development, the application field of LED has developed from the initial simple electrical indicator light and LED display to other fields such as LED backlight, landscape lighting, and interior decoration lights, especially in automobile taillights, billboards, decorative lighting, In the lighting application of refrigerators and washing machines, LEDs are replacing the original neon lamps and tungsten filament bulbs in large quantities, and have huge market potential. However, LED driver desi...

AI Technical Summary

Problems solved by technology

In LED applications such as automotive tail lights, switching regulators are complex in design and have electromagnetic interference, which is not suitable. Linear regulators are not very economical. Resistive drivers are lower in cost and simple in structure, but the operating current of this driver It has a linear relationship with the working voltage. Under low voltage conditions, the forward current is low, which will lead to insufficient brightness of the LED. damage

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