Galvanic Isolation Circuit for LED Modules Using Single Optocoupler
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing voltage supply circuits for LEDs require two separate optocouplers for transmitting overvoltage and digital data, which is inefficient and complex.
Innovation Solution
The overvoltage information is superimposed on the digital protocol, allowing a single optocoupler to transmit both overvoltage and other measurement data from the secondary side to the primary side, eliminating the need for an additional signal transmitter and ensuring rapid feedback in case of an overvoltage condition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If two separate optocouplers are used to transmit overvoltage signals and digital data, then reliable signal transmission is achieved, but device complexity and component count increase
Solution Approach 1:
The patent combines the overvoltage signal transmission and digital data transmission into a single optocoupler channel. The overvoltage detection circuit generates an analog signal that is superimposed onto the digital data bus, allowing both types of information to be transmitted through one optocoupler instead of requiring separate optocouplers for each signal type.
Solution Approach 2:
The single optocoupler is designed to handle multiple functions: it transmits both the overvoltage alarm signals and the digital operating parameters from the secondary side to the primary side. The evaluation circuit on the primary side distinguishes between these different types of information by analyzing the signal characteristics on the shared communication channel.
2Device complexity
If a single optocoupler is used for both overvoltage and digital data transmission, then device complexity is reduced, but signal transmission reliability may deteriorate
Solution Approach 1:
The system implements feedback mechanisms where the primary-side control circuit continuously monitors the shared communication channel for overvoltage conditions. When an overvoltage condition is detected through the analysis of signal characteristics, the control circuit responds by adjusting the LED module operation, thereby maintaining system reliability despite the shared transmission medium.
Solution Approach 2:
The invention utilizes changes in signal parameters (voltage levels, signal duration, pulse patterns) to encode different types of information on the shared optocoupler channel. The overvoltage alarm is transmitted by modifying the electrical parameters of the signal in a way that can be distinguished from normal digital data by the evaluation circuit, maintaining reliable signal differentiation without requiring separate physical channels.
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 simplifies the circuit by using a single optocoupler for both data types, prioritizing overvoltage signals for quick reaction, and maintaining efficient data transmission while reducing component count and complexity.
Implementation Method 1
a single optocoupler to transmit both overvoltage and other measurement data from the secondary side to the primary side
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The invention relates to a cyclical, galvanically isolated voltage supply circuit (1) for operating an LED module (2), having a galvanic separating element (T), on the primary side of which a switch (SI) is provided which is clocked by a first control circuit (ST1) and of which the secondary side is guided to terminals for the LED module (2). Furthermore a second control circuit (ST2) is provided which is disposed in terms of potential on the secondary side of the galvanic separating element (T), and which is designed to communicate at least unidirectionally with the first control circuit (ST1) by means of a digital protocol via a preferably electrically isolated signal transmitter (Opto), for example an optocoupler, in order to forward operating parameters of the LED module (2) to the first control circuit (ST1). Furthermore on the secondary side a circuit (3) is provided for detecting an overvoltage state, wherein an output signal from the detection circuit (3) is likewise transmitted via the signal transmitter (Opto), which is also used for forwarding the operating parameters, wherein the output signal from the detection circuit (3) bypasses the second control circuit (ST2) and is delivered to the signal transmitter (Opto).