Power Supply IC Temperature Switching Without a Dedicated Thermistor Pin
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing integrated circuits in power supply circuits face challenges in temperature detection, as using a thermistor requires a dedicated terminal, limiting flexibility in setting the predetermined temperature, and internal temperature detection elements are fixed, making it difficult to adjust.
Innovation Solution
The integrated circuit incorporates a detection resistor for temperature detection, with two temperature detection circuits that allow for flexible temperature setting, and a switching control circuit to stop transistor switching when predetermined temperatures are exceeded, using either an internal or external thermistor configuration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a thermistor is used for temperature detection, then the predetermined temperature can be flexibly changed by selecting different thermistors, but a dedicated terminal needs to be provided in the integrated circuit
Solution Approach 1:
The first terminal is designed to serve multiple functions: it can detect temperature through an internal temperature detection element when no external component is connected, or it can detect temperature through an external thermistor when connected. This multi-functionality eliminates the need for a separate dedicated terminal for thermistor connection, resolving the contradiction between adaptability and device complexity
Solution Approach 2:
The integrated circuit uses its own internal resources (the first terminal and internal circuitry) to accommodate external thermistor connections without requiring additional dedicated terminals. The existing terminal structure serves both internal and external temperature detection needs, making the system self-sufficient
2Device complexity
If a temperature detection element is provided in the integrated circuit, then temperature detection is integrated, but it is difficult to change the predetermined temperature
Solution Approach 1:
The system dynamically switches between two temperature detection modes: internal temperature detection element mode and external thermistor mode. The first terminal can be configured to work with either the internal detection element or an externally connected thermistor, allowing the predetermined temperature to be changed by simply connecting or disconnecting the external thermistor without modifying the integrated circuit structure
Solution Approach 2:
The first terminal acts as an intermediary that can interface with both the internal temperature detection element and an external thermistor. This intermediary structure enables the system to switch between integrated and external temperature detection methods, providing flexibility in setting the predetermined temperature while maintaining integration benefits
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enables flexible temperature detection and protection against overheating, ensuring reliable operation of the power supply circuit by stopping transistor switching when temperatures rise, thus preventing damage.
Implementation Method 1
a first temperature detection circuit having a temperature detection element, the first temperature detection circuit being configured to detect a first temperature, based on a voltage of the temperature detection element
Implementation Method 2
a second temperature detection circuit configured to detect a second temperature, based on a first voltage corresponding to a resistance value of the detection resistor
Data Source
AI summary
An integrated circuit for a power supply circuit that includes a detection resistor. The integrated circuit includes: a first pad; a first terminal coupled to the detection resistor, the first terminal being electrically connected to the first pad in a first case, and being electrically separated from the first pad in a second case; a first temperature detection circuit having a temperature detection element, and being configured to detect a first temperature based on a voltage of the temperature detection element; a second temperature detection circuit configured to detect a second temperature of the integrated circuit, based on a first voltage corresponding to a resistance value of the detection resistor, received through the first pad in the first case; and a circuit configured to operate based on results of detection of the second and first temperature detection circuits, respectively in the first case and in the second case.