Adaptive Switching Converter and LDO for Power Efficiency
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Solution Overview
Problem
Existing power management systems with cascaded switching converters and linear regulators suffer from inefficiency due to fixed output voltages and reliance on peak load conditions, leading to power inefficiency across varying load conditions.
Innovation Solution
A power conversion arrangement that includes a switching converter with a feedback ladder of resistors and a linear regulator with a sense transistor, allowing for real-time load current sensing and adaptation of the switching converter's output voltage, reducing the drop-out voltage across the linear regulator in light or moderate load conditions, thereby enhancing overall power efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the switching converter's output voltage is fixed for peak load conditions, then the linear regulator can provide accurate output voltage with low ripple, but power efficiency deteriorates for light or moderate load conditions
Solution Approach 1:
The invention makes the switching converter's output voltage dynamic by adjusting it according to the actual load current. The control circuitry senses the load current and modifies the switching converter's output voltage accordingly, transitioning from a fixed voltage design to an adaptive one that matches the actual power requirements, thereby reducing unnecessary power dissipation in the linear regulator during light or moderate load conditions
Solution Approach 2:
The invention changes the operating parameters of the switching converter based on load conditions. By varying the output voltage of the switching converter as a function of load current, the system optimizes the power distribution between the switching converter and linear regulator, reducing the voltage drop across the linear regulator and thereby minimizing power losses while maintaining output voltage accuracy
2Manufacturing precision
If the linear regulator is designed for minimum drop-out voltage at peak load current, then accurate voltage regulation is achieved, but power efficiency worsens for all other load conditions
Solution Approach 1:
The invention dynamically adjusts the switching converter's output voltage based on the actual load current sensed by the control circuitry. This dynamic adjustment allows the linear regulator to operate with optimized drop-out voltage for each load condition rather than being designed for peak load, reducing power dissipation during light or moderate loads while maintaining voltage regulation accuracy
Solution Approach 2:
The invention implements a feedback mechanism where the control circuitry senses the load current and uses this information to adjust the switching converter's output voltage. This closed-loop control ensures that the system adapts to varying load conditions, optimizing power efficiency by reducing the voltage drop across the linear regulator when full power is not required, while maintaining accurate voltage regulation
3Manufacturing precision
If output voltage is adjusted based on feedback from linear regulator, then voltage accuracy is maintained, but power efficiency deteriorates
Solution Approach 1:
The invention implements feedback control where the control circuitry monitors the load current and adjusts the switching converter's output voltage accordingly. This feedback mechanism enables the system to optimize power distribution by reducing the switching converter's output voltage when the load requires less power, thereby reducing the voltage drop and power dissipation in the linear regulator while maintaining accurate output voltage regulation
Solution Approach 2:
The invention changes the output voltage parameter of the switching converter as a function of load current. By adjusting this parameter dynamically rather than maintaining a fixed high voltage, the system reduces unnecessary power dissipation in the linear regulator while keeping the output voltage accurate for the actual load requirements
Data Source
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AI summary
In one embodiment a power conversion arrangement comprises a switching converter (DC) with an input which is supplied with an input voltage (Vin) and a first output (Out1) to provide a first output voltage (Vout1) as a function of the input voltage (Vin), a linear regulator (LDO1) with an input coupled to the first output (Out1) of the switching converter (DC), the linear regulator (LDO1) having a second output (Out2) to provide a second output voltage (Vout2) as a function of the first output voltage (Vout1) to a connectable electrical load (CS), means for sensing (MSI) a load current (Iload) at the second output (Out2) of the linear regulator (LDO1), the means being connected to the second output (Out2) of the linear regulator (LDO1), and means for influencing (MVA) the first output voltage (Vout1) as a function of the load current (Iload), the means (MVA) being connected to the first output (Out1) of the switching converter (DC) and to the means for sensing (MSI) the load current (Iload). Furthermore, a power management circuit and a method for power conversion are described.