Stacked Voltage Regulator Drivers With Interleaved Ripple Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power management circuits face inefficiencies such as voltage overshoots, increased output noise, and impractical solutions like interleaving or continuously scalable capacitive VRs that compromise efficiency and power density.
Innovation Solution
Implementing a secondary stacked transistor voltage driver with time-shifted control signals, a precharge circuit, and a switching schema for interleaved switching converters, along with a multi-stage approach combining fixed-ratio and continuous capacitive voltage converter stages.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If stacked devices are used to provide higher voltage capabilities, then voltage capability is improved, but efficiency deteriorates due to parasitic capacitances causing voltage overshoots and larger voltage swings
Solution Approach 1:
The precharge circuit charges the intermediate node to a predetermined voltage level before the stacked transistor switches on. This preliminary action prevents voltage overshoot and reduces stress on the transistor by ensuring the node is already at the appropriate voltage level when the switch closes, thereby maintaining efficiency while enabling higher voltage capability.
2Loss of energy
If switching converters are used to improve efficiency, then efficiency is improved, but output noise increases due to voltage ripple
Solution Approach 1:
The patent employs interleaved switching of multiple stacked transistor pairs with different switching phases. By periodically switching the transistors in an interleaved manner rather than simultaneously, the voltage ripple at the output is reduced because the ripples from different phases cancel each other out, thereby reducing output noise while maintaining switching converter efficiency.
3Object-generated harmful factors
If interleaving is used to reduce voltage ripple, then voltage ripple is reduced, but device complexity increases significantly with more than 40 capacitors and 500 transistors
Solution Approach 1:
The patent merges multiple stacked transistor pairs into a single integrated circuit structure where they share common nodes, capacitors, and control logic. This consolidation allows the interleaved switching functionality to be achieved with a manageable number of components rather than requiring separate implementations of each capacitor and transistor, thereby reducing overall device complexity while maintaining ripple reduction benefits.
4Loss of energy
If continuously scalable capacitive VRs are used to improve regulation efficiency, then regulation efficiency is improved, but power density decreases due to stacked devices requirement
Solution Approach 1:
The precharge circuit performs preliminary charging of intermediate nodes to the correct voltage levels before the main switching operation. This allows the capacitive voltage regulator to operate efficiently across a scalable voltage range without requiring stacked transistor configurations, as the precharging prepares the nodes to handle the voltage transitions smoothly. This maintains power density while achieving regulation efficiency.
Data Source
AI summary
Power driver circuits may be used to provide higher voltage capabilities beyond what may managed by a single transistor. To reduce or eliminate effects associated with a stacked transistor voltage driver, a secondary stacked transistor voltage driver may be separated from a primary stacked transistor voltage driver, where the secondary driver is driven using time-shifted control signals. A switching schema may be used to interleave the several cells of a single continuous capacitive voltage regulator. A multi-stage approach may include both a number of fixed-ratio or multi-ratio capacitive voltage converter stages and final stage that is switched out of phase from the preceding stages, where the final stage includes a continuously scalable capacitive converter.