Charge Pump Circuit Timing Control for Leakage Reduction

Solution Overview

Problem

Dual-phase charge pump circuits suffer from low efficiency due to delayed charging and discharging of capacitors, which leads to reverse leakage current and delayed turn-off times of transfer transistors, resulting in inefficient power supply.

Innovation Solution

A charge pump circuit design incorporating dual-phase charge pumps, load switches, and a control circuit that manages the switching of load switches based on specific clocks to prevent reverse leakage current by ensuring that pumping voltages are transferred only when the corresponding load switches are off, thereby improving efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If capacitors C3 and C4 are used for charging and discharging nodes ND1 and ND2, then the voltage pumping operation can be performed, but the charging and discharging process is delayed causing reverse leakage current

Engineering Contradiction:

Improvepower supply efficiencyVSAvoidreverse leakage current

Core Design Contradiction:

PowerVSLoss of energy

Solution Approach 1:

The control circuit proactively turns off the transfer transistors P1 and P2 before the capacitors C3 and C4 complete their charging/discharging cycles. This preliminary action prevents the reverse leakage current from occurring in the first place, rather than trying to compensate for it afterward. The control signals are timed to advance the turn-off moment, ensuring that the transfer transistors are already off when the delayed charging/discharging would otherwise cause leakage.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The control circuit monitors the states of nodes ND1 and ND2 and adjusts the turn-off timing of transfer transistors P1 and P2 accordingly. By using feedback from the node states, the control circuit can dynamically optimize the timing to prevent reverse leakage while maintaining efficient power transfer, resolving the contradiction between power efficiency and energy loss.

Inventive Principle:

Principle #23Feedback

2Productivity

If transfer transistors P1 and P2 are turned on to transfer pumping voltage, then power can be supplied to output terminal, but delayed turn-off causes power to flow back to power source

Engineering Contradiction:

Improvepower transfer efficiencyVSAvoidreverse current flow

Core Design Contradiction:

ProductivityVSLoss of energy

Solution Approach 1:

The control circuit proactively turns off the transfer transistors P1 and P2 before the capacitors C3 and C4 complete their charging/discharging cycles. This preliminary action prevents the reverse leakage current from occurring in the first place, rather than trying to compensate for it afterward. The control signals are timed to advance the turn-off moment, ensuring that the transfer transistors are already off when the delayed charging/discharging would otherwise cause leakage.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The control circuit monitors the states of nodes ND1 and ND2 and adjusts the turn-off timing of transfer transistors P1 and P2 accordingly. By using feedback from the node states, the control circuit can dynamically optimize the timing to prevent reverse leakage while maintaining efficient power transfer, resolving the contradiction between power efficiency and energy loss.

Inventive Principle:

Principle #23Feedback

3Power

If dual-phase charge pump operation is performed, then voltage pumping can be achieved, but capacitor delay causes inefficient power supply

Engineering Contradiction:

Improvevoltage pumping capabilityVSAvoidcharging and discharging delay

Core Design Contradiction:

PowerVSLoss of time

Solution Approach 1:

The control circuit proactively turns off the transfer transistors P1 and P2 before the capacitors C3 and C4 complete their charging/discharging cycles. This preliminary action prevents the reverse leakage current from occurring in the first place, rather than trying to compensate for it afterward. The control signals are timed to advance the turn-off moment, ensuring that the transfer transistors are already off when the delayed charging/discharging would otherwise cause leakage.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The control circuit monitors the states of nodes ND1 and ND2 and adjusts the turn-off timing of transfer transistors P1 and P2 accordingly. By using feedback from the node states, the control circuit can dynamically optimize the timing to prevent reverse leakage while maintaining efficient power transfer, resolving the contradiction between power efficiency and energy loss.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS20230155496A1Charge pump circuit

Publication Date: 2023.05.18 GUTSCHSEMI LTD

AI summary

A charge pump circuit is provided. The charge pump circuit includes a dual-phase charge pump, a first load switch, a second load switch, and a control circuit. The dual-phase charge pump performs a voltage pumping operation on a power source in response to a first clock and a second clock to generate a first pumping voltage at a first node and a second pumping voltage at a second node. The control circuit controls the first load switch in response to a third clock and controls the second load switch in response to a fourth clock. In a period during which the first load switch is turned off, the second load switch transfers the first pumping voltage to an output terminal of the charge pump circuit. In a period during which the second load switch is turned off, the first load switch transfers the second pumping voltage to the output terminal.