Starting circuit for bias circuit

Abstract

The invention provides a starting circuit of a bias circuit, which utilizes a switch to provide an actuated signal so as to draw the bias circuit out of a null state, the switch is driven by a pulse from an external pulse provider or a combined pulse generator, the bias circuit enters a stable operating state after the pulse, and the starting circuit stops operating. Therefore, the starting circuit has the advantages of large-scale voltage supply, no standby current, short starting time, simple circuit layout, etc.

Description

technical field [0001] The invention relates to a start-up circuit which does not consume standby current and can be applied to a wide range of voltage supplies. Background technique [0002] The start-up circuit is used to pull up a zero-state (also referred to as zero-current state) bias circuit to a stable operating state to activate an electronic device. An ideal start-up circuit requires no standby current, simple circuit design, application to a wide range of supply voltages, and short start-up time. [0003] figure 1 It is a schematic diagram of a bias circuit, used to describe a conventional bias circuit in conjunction with the following paragraphs. One end of the bias circuit 100 is connected to a voltage source of a voltage VCC, and the other end is grounded. The bias circuit 100 includes a left leg and a right leg to form a current-mirror-based bias circuit. The left bridge arm contains a p-channel metal oxide silicon field effect transistor (PMOS) MP 1 and a...

AI Technical Summary

Problems solved by technology

When the supply voltage drops, the start-up circuit will not be able to generate the same current as when the supply voltage is high, which will increase the start-up time

[0005] Nowadays, many different starting circuits have been proposed, but some starting circuits cannot meet the requirements of a wide range of voltage supply or no standby current requirements, and some starting circuits cannot meet the requirements of short startup time or simple circuit design.

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