Starting circuit for wide power band gap reference source

Abstract

The invention relates to the technical field of an integrated circuit, and in particular to a non-overshoot starting circuit for a wide power band gap reference source. The starting process is divided into two stages, the first stage is an enabling control start process, the initial stage of the second stage is combined with a two-stage load pipe in an operational amplifier to form a feedback loop, and output current is adjusted to be within a non-overshoot controllable range, so that non-ideal overshoot phenomenon in the start process is effectively avoided; meanwhile, a current path is kept in the circuit, so that the circuit enters a later stage to rapidly build reference voltage. Due to existence of soft start of the feedback loop, the starting circuit is free of overshoot when being started at high voltage, and can ensure enough start current when being started at low voltage, so that the reference normally works. Thus, application of non-overshoot and wide power supply range is achieved. The starting circuit disclosed by the invention is particularly applied to the starting circuit for the wide power band gap reference source.

Description

technical field [0001] The invention relates to the technical field of integrated circuits, in particular to a non-overshoot starting circuit for a wide power bandgap reference source. Background technique [0002] The reference voltage source is an important component unit module in an analog integrated circuit chip, which is used to generate a voltage reference that does not change with the power supply voltage and temperature, and provides a reference voltage for other circuit modules. Since the reference voltage source is often accompanied by two stable states, in order to ensure that the reference circuit can successfully get rid of the non-ideal state of zero current after power-on, and reduce the adverse effects caused by the offset voltage and offset current during power-on, it is necessary to design a startup circuit, to ensure that the circuit can still work normally after a disturbance occurs in the reference circuit, and after the reference source works normally,...

AI Technical Summary

Problems solved by technology

But such start-up current is uncontrollable, especially in high-voltage applications, the start-up current is too large and the output overshoot is not ideal.

However, if you want to take into account the fact that there is no overshoot when starting at high voltage, the starting current at low voltage may be too small, and the reference cannot be started normally, which cannot adapt to the application of a wide power supply range.

Similarly, the above-mentioned problems also exist in the conventional start-up method using a large resistance or a large capacitance.

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