Continuous Level Shifter Circuit for Reliable High-Side Turn-Off
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pulse-based level shift circuits for high side transistors in high voltage applications are prone to missing reset current pulses, leading to failure in turning off the transistors, and are relatively slow in responding to current pulses.
Innovation Solution
A continuous signal level shift circuit that generates continuous set and reset currents based on the logic state of the input control signal, eliminating the risk of missing pulses and providing faster response times compared to pulse-based systems.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If pulse-based level shift circuits are used, then the circuit structure is simpler, but the reliability deteriorates due to missing reset current pulses causing transistor failure to turn off
Solution Approach 1:
The patent employs a current source that continuously generates either a set current or a reset current based on the logic state of the control signal, rather than using discrete pulses. This continuous current delivery ensures that the comparator always has a valid signal to process, eliminating the risk of missing reset pulses and ensuring reliable transistor turn-off while maintaining relatively simple circuit structure
2Speed
If pulse-based level shift circuits are used, then the response time can be fast, but the reliability deteriorates due to missing pulses
Solution Approach 1:
The continuous current generation approach ensures that the comparator receives uninterrupted signals, eliminating the possibility of missing pulses while maintaining fast response times. The circuit transitions smoothly between set and reset states without gaps, ensuring both speed and reliability in transistor switching operations
3Reliability
If continuous signal level shift circuit is used, then the reliability improves by eliminating missed pulses, but the device complexity increases
Solution Approach 1:
The patent achieves high reliability through a relatively simple continuous current generation approach using a current source and comparator, avoiding the need for complex pulse generation and timing circuits while ensuring uninterrupted signal delivery for reliable transistor switching
Solution Approach 2:
The comparator continuously monitors the current state and provides feedback to the latch, which maintains the appropriate state until a valid transition occurs. This feedback mechanism ensures reliable state management without requiring complex control logic, as the system naturally responds to valid current transitions while ignoring invalid or incomplete signals
Data Source
AI summary
A driver includes a current generator having an input and first and second outputs. The current generator generates a first current at the first output while a signal at the input is at a first logic state and generates a second current at the second output while the signal at the input is at a second logic state. A comparator has a first comparator input, a second comparator input, and a first comparator output, and a second comparator output. The first comparator input is coupled to the first output, and the second comparator input is coupled to the second output. A latch has a first latch input, a second latch input, and a latch output. The first latch input is coupled to the first comparator output, and the second latch input is coupled to the second comparator output. A gate control circuit has an input coupled to the latch output.