Bandgap Reference Circuit Sharing One Current Source for Voltage and Current

Solution Overview

Problem

Current bandgap reference sources in integrated circuits require separate circuits for voltage and current references, leading to high costs and chip area wastage due to the temperature coefficient of semiconductor resistances.

Innovation Solution

A reference source circuit that generates both bandgap reference voltage and current using a single circuit with a first current generating unit, a reference voltage generating unit, and a reference current generating unit, incorporating transistors, resistors, and capacitors to achieve simultaneous operation and multiplexing, thereby saving cost and chip area.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If two separate circuits are prepared for bandgap voltage source and bandgap current source, then both reference sources can be achieved, but chip area increases and cost increases

Engineering Contradiction:

Improvereference source functionalityVSAvoidchip area

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The patent merges the bandgap voltage source circuit and bandgap current source circuit into a single integrated reference source circuit. The first current generating unit generates a first current that is simultaneously used by both the reference voltage generating unit (which generates bandgap reference voltage) and the reference current generating unit (which generates bandgap reference current). This combining of functions into one circuit achieves both reference sources while reducing chip area and cost compared to using two separate circuits.

Inventive Principle:

Principle #5Merging (Combining)

2Reliability

If two separate circuits are prepared for bandgap voltage source and bandgap current source, then both reference sources can be achieved, but manufacturing cost increases

Engineering Contradiction:

Improvereference source functionalityVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent merges the bandgap voltage source circuit and bandgap current source circuit into a single integrated reference source circuit. The first current generating unit generates a first current that is simultaneously used by both the reference voltage generating unit (which generates bandgap reference voltage) and the reference current generating unit (which generates bandgap reference current). This combining of functions into one circuit achieves both reference sources while reducing chip area and cost compared to using two separate circuits.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The first current generating unit serves multiple functions: it provides the first current to the reference voltage generating unit for generating bandgap reference voltage, and simultaneously provides the first current to the reference current generating unit for generating bandgap reference current. This multi-functionality reduces the overall circuit complexity and manufacturing cost while achieving both reference source functionalities.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS12164318B2Reference source circuit, chip, power supply, and electronic apparatus

Publication Date: 2024.12.10 CHIPONE TECHNOLOGY (BEIJING) CO LTD

AI summary

Provided are a reference source circuit, a chip, a power supply, and an electronic device. The circuit comprises: a first current generation unit used for generating first current; a reference voltage generation unit electrically connected to the first current generation unit and used for generating a band-gap reference voltage by using the first current; and a reference current generation unit electrically connected to the first current generation unit and the reference voltage generation unit and used for generating band-gap reference current by using the first current. By means of the circuit above, a band-gap reference voltage and band-gap reference current can be generated in a reference source circuit, and the first current generation unit may be reused, so that high-gain and simultaneous work of two loops can be achieved, the cost can be reduced, and the chip area can be saved as compared with the design of two separate reference sources.