Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Constant current source capable of adjusting positive and negative temperature coefficients and adjustment method thereof

A technology with negative temperature coefficient and positive temperature coefficient, applied in the field of constant current source, can solve the problem that thermistor is not easy to integrate

Active Publication Date: 2013-10-09
MORNSUN GUANGZHOU SCI & TECH
View PDF8 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] The first purpose of the present invention is to provide a constant current source with adjustable positive and negative temperature coefficients, which can obtain any desired positive and negative temperature coefficient current sources through simple calculation and ratio, which not only improves the difficulty of integration of thermistors At the same time, the method involved in the present invention can not only improve the negative temperature coefficient of the current, but also can improve the positive temperature coefficient of the current, and the present invention has the advantages of wide applicability and strong practicability

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Constant current source capable of adjusting positive and negative temperature coefficients and adjustment method thereof
  • Constant current source capable of adjusting positive and negative temperature coefficients and adjustment method thereof
  • Constant current source capable of adjusting positive and negative temperature coefficients and adjustment method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0077] The present invention relates to integrated circuits, and more specifically, the present invention can be used in all switching power supply controllers that require current bias with a large temperature coefficient. According to various embodiments, the present invention provides various schemes for enhancing the temperature coefficient.

[0078] Such as Figure 5 As shown, the adjustable positive and negative temperature coefficient constant current source of the first embodiment includes a first constant current source A1, a second constant current source A2, a weighted subtraction circuit A3 and a current amplification circuit A4; the first constant current source A1 and The temperature coefficient of the second constant current source A2 is positive and negative, and the output terminals of the first constant current source A1 and the second constant current source A2 are respectively connected to the minuend input terminal and the subtrahend input terminal of the we...

Embodiment 2

[0116] Such as Figure 7 Shown is the second embodiment of the constant current source of the present invention. The difference between the second embodiment and the first embodiment is that the circuit for generating positive and negative temperature coefficients is different from the circuit in the first embodiment.

[0117]The first constant current source A1 includes operational amplifier U1, PMOS transistors P601, P602, P603, P604, NMOS transistor N601 and resistor R601, which form a constant current source circuit and correspond to the first operational amplifier and the third constant current source circuit respectively. , four, five, six PMOS tubes, the fifth NMOS tube and the second resistor; the second constant current source A2 includes operational amplifier U2, PMOS tubes P605, P606, P607, P608, NMOS tube N602 and resistor R602, which also form a constant The current source circuit corresponds to the first operational amplifier, the third, fourth, fifth and sixth P...

Embodiment 3

[0126] Such as Figure 8 Shown is the third embodiment of the constant current source of the present invention, which includes a first constant current source A1, a second constant current source A2 and a weighted subtraction circuit A3.

[0127] Among them, the first constant current source A1 is a negative temperature coefficient current source circuit, which is composed of the seventh PMOS transistor P801, the third resistor R801, the first triode Q801, the second triode Q802 and the fourth resistor R802, and the seventh The source of the PMOS transistor is connected to the power supply terminal, the gate is connected to the drain, and one of the connection points is connected to the collector of the second transistor, and the other is connected to the base of the second transistor through the third resistor. The base of the second transistor is connected to the collector of the first transistor, the emitter is connected to the base of the first transistor, and the base of ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
Resistance valueaaaaaaaaaa
Login to View More

Abstract

The invention discloses a constant current source capable of adjusting positive and negative temperature coefficients and an adjustment method thereof. The constant current source comprises a first constant current source body (A1), a second constant current source body (A2) and a weighted subtraction operational circuit (A3). The temperature coefficient of the first constant current source body (A1) and the temperature coefficient of the second constant current source body (A2) are opposite in positive and negative polarities, an output end of the first constant current source body (A1) and an output end of the second constant current source body (A2) are connected to a minuend input end of the weighted subtraction operational circuit (A3) and a subtrahend input end of the weighted subtraction operational circuit (A3) respectively, and constant currents adjustable in the positive and negative temperature coefficients are outputted through the weighted subtraction operational circuit (A3) by means of adjustment of weighting coefficients of the first constant current source body (A1) and the second constant current source body (A2). The constant current source can conveniently adjust obtained arbitrary positive and negative temperature coefficients.

Description

technical field [0001] The invention relates to a constant current source with adjustable positive and negative temperature coefficients and a method for adjusting the constant current source. Background technique [0002] The traditional ideal constant current source is defined as a current that does not vary with voltage and temperature, and the current value has a zero temperature coefficient. [0003] figure 1 The start-up circuit in the traditional self-excited push-pull converter circuit shown uses a resistive element, that is, the first resistor R101 in the figure, so that the start-up current flowing through the resistor remains almost unchanged, and this scheme will lead to self-excited The push-pull converter has the disadvantages of low-temperature start-up difficulty and high-temperature short-circuit burnout, and making the start-up current have negative temperature characteristics can solve the disadvantages of low-temperature start-up difficulty and high-temp...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G05F1/567
Inventor 曾正球
Owner MORNSUN GUANGZHOU SCI & TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com