Reference voltage source compensated by positive temperature coefficient currents

Abstract

The invention discloses a reference voltage source with positive temperature coefficient current compensation. A positive temperature coefficient current compensation circuit is added at the output end of the reference voltage source, and two NPN tubes Q8 and Q9 and corresponding resistors R7 and R8 are used to generate the temperature coefficient Different two groups of positive temperature coefficient currents are superimposed to optimize the temperature change rate of the current. The invention solves the application limitation of the traditional bandgap reference, changes the limitation that the traditional first-order bandgap reference can only generate negative temperature coefficient in the high temperature range, and relies on the positive temperature coefficient of the reference in the full temperature range to provide high-current power switching power supply. A simple structure, low cost, stable and reliable output voltage compensation scheme is proposed.

Description

technical field [0001] The invention relates to a reference voltage source, in particular to a reference voltage source for positive temperature coefficient current compensation used in a power management chip, and belongs to the field of integrated circuit power supply design. Background technique [0002] The voltage reference is an important part of the analog circuit, especially the power management chip that needs to maintain a stable output voltage. It needs a voltage reference with high precision and good temperature coefficient to stabilize the output voltage. The traditional bipolar process (bipolar process is an integrated circuit process in which the main active device is a bipolar transistor, and the bipolar transistor is commonly referred to as a triode) bandgap reference uses bipolar transistors working at different current densities. Polar transistors, whose voltage difference has a positive temperature coefficient, and bipolar transistors, whose emitter turn-...

AI Technical Summary

Problems solved by technology

This kind of reference can meet the requirements in ordinary applications, but in some applications with special requirements, the performance of ordinary voltage references is not enough to meet the requirements

In order to compensate the output voltage drop caused by line loss and load adjustment when the power management chip is under heavy load, it is necessary to add additional complex circuits for compensation

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