Detector Circuit for AC Presence and Discharge Monitoring
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for reducing power consumption in switching mode power supplies are not cost and time efficient, and may not meet the discharge requirements of X capacitors as specified in IEC 60950 Safety guidelines, often requiring additional large and expensive components that are lossy.
Innovation Solution
A method and structure for determining whether an AC signal is coupled to a power supply, involving a comparator, delay elements, and a timer to generate an indicator signal when the power supply is disconnected from an AC signal source, using a voltage scaling network and edge detectors to efficiently manage energy storage and conduction modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If additional components are used to meet discharge requirements, then reliability is improved, but device complexity and cost increase
Solution Approach 1:
The existing comparator and timer circuits are made multi-functional by configuring them to perform both their original functions and the new AC presence detection function. The comparator compares signals to detect AC presence, and the timer provides both its original timing function and discharge monitoring, eliminating the need for separate dedicated components for discharge requirements.
Solution Approach 2:
The patent combines multiple functions into existing circuit blocks. The comparator circuit is merged with AC detection functionality, and the timer circuit is merged with discharge monitoring functionality. This consolidation achieves discharge requirement compliance without adding separate component modules.
2Reliability
If additional components are used to meet discharge requirements, then reliability is improved, but manufacturing cost increases
Solution Approach 1:
Existing components are configured to perform multiple functions including discharge monitoring. The comparator and timer circuits handle both their original tasks and AC presence/discharge detection, eliminating the need for additional expensive components and reducing manufacturing costs while meeting IEC 60950 discharge requirements.
3Use of energy by moving object
If power consumption is reduced, then energy efficiency is improved, but discharge requirements may not be met
Solution Approach 1:
The circuit uses the existing operational signals and power already present in the system to perform discharge monitoring. The comparator and timer utilize existing voltage rails and signal edges, requiring no additional power supply infrastructure. This self-service approach maintains discharge compliance without increasing power consumption.
4Use of energy by moving object
If existing power consumption reduction techniques are used, then energy efficiency is improved, but they are lossy and require additional components
Solution Approach 1:
The discharge monitoring function utilizes existing system resources including power rails, signal edges, and operational amplifier circuits that are already consuming power for their primary functions. By making these circuits multi-functional, the system avoids additional energy loss that would result from separate dedicated monitoring components.
Data Source
Figure 1~4
Figure 3
Figure 5~6
AI summary
In accordance with an embodiment, a controller includes a comparator, a delay element, and a timer. The delay element is connected to an input terminal of the comparator and the timer is connected to an output terminal of the comparator. The delay element may include a switch having a control electrode coupled for receiving a control signal. In accordance with another embodiment, a detection signal is generated in response to a comparison signal transitioning to a first level.