Programmable Gate Voltage Switching for Power Module On-Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power module systems face challenges in adjusting gate voltage to prevent damage due to excessive supply voltage and require slow on-resistance adjustments for thermal management and short circuits, which are not adequately addressed by programmable LDO regulators.
Innovation Solution
Implementing a gate driver with a controller and buffer to adjust gate-source voltage (Vgs) dynamically, using a reference voltage to prevent exceeding absolute maximum ratings and enable fast on-resistance adjustments under various conditions, including fault scenarios.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional power module systems use fixed supply voltage to drive power modules, then the system structure is simple, but the gate voltage cannot be adjusted to prevent damage due to excessive supply voltage and cannot enable fast on-resistance adjustments for thermal management and short circuits
Solution Approach 1:
The patent implements dynamic gate voltage adjustment by switching between a full supply voltage (VCC) and a reduced reference voltage (VREF) based on operational conditions. The controller dynamically selects which voltage source to connect to the power module gate through switch control, enabling adaptability for different operating scenarios such as normal operation, thermal management, and short circuit protection without requiring a completely complex programmable voltage regulator system.
Solution Approach 2:
The patent introduces a reference voltage buffer circuit as an intermediary between the supply voltage source and the power module gate. This buffer provides a stable, reduced voltage level (VREF) that acts as a mediator to limit gate voltage under specific conditions. The buffer circuit includes operational amplifiers and resistors that generate and maintain the reference voltage level, serving as an intermediate voltage source that protects the power module while maintaining system simplicity.
2Speed
If programmable LDO regulators are used to adjust on-resistance, then voltage control is possible, but the adjustment speed is too slow for thermal management and short circuit scenarios
Solution Approach 1:
The patent employs periodic or conditional voltage switching rather than continuous gradual adjustment. The controller periodically evaluates operational conditions (such as temperature thresholds or fault detection) and switches the gate voltage between VCC and VREF accordingly. This periodic action enables fast response to thermal management needs and short circuit conditions, achieving high-speed on-resistance adjustment without the slow continuous regulation characteristic of LDO regulators.
Solution Approach 2:
The patent changes the gate voltage parameter abruptly between two discrete levels (VCC and VREF) rather than using gradual continuous adjustment. This parameter change approach allows instantaneous transition of the power module's on-resistance state, providing fast response for thermal management and short circuit protection. The reference voltage VREF is specifically set to achieve a desired on-resistance value for protection scenarios, enabling reliable fast protection effectiveness.
3Reliability
If the supply voltage is reduced to a reference voltage level, then power module damage is prevented, but the driving capability for normal operation may be insufficient
Solution Approach 1:
The system dynamically adjusts the gate voltage based on real-time operational conditions. During normal operation when high driving capability is needed, the full supply voltage VCC is applied to the power module gate for optimal performance. When protection is needed (thermal management or short circuit conditions), the system switches to the reduced reference voltage VREF to limit power module stress. This dynamic switching resolves the contradiction by providing both high power capability and reliable protection at different times.
Solution Approach 2:
The controller periodically monitors operational parameters and switches between full voltage drive and reduced voltage protection modes as needed. This periodic evaluation and switching enables the system to maintain high driving capability during normal operation while providing reliable protection when conditions require it, preventing power module damage without sacrificing normal operational performance.
Data Source
AI summary
Semiconductor devices, systems and methods are described. A semiconductor device can include a driver configured to output a gate current to drive a power module. The semiconductor device can further include a buffer configured to buffer a reference voltage that is less than a supply voltage being provided to the driver. The semiconductor device can further include a controller configured to determine a gate voltage of the power module is equivalent to the reference voltage. The controller can, in response to determination that the gate voltage is equivalent to the reference voltage, disable the driver to cause the driver to stop providing the gate current to the power module and enable the buffer to supply the reference voltage to the power module.