Ring-Oscillator Charge Pump With Feedback Voltage Stabilization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional charge pumps for semiconductor memory devices face issues with excessive output and power consumption in high-voltage states, and their performance is sensitive to ambient temperature and voltage variations, leading to instability.
Innovation Solution
A charge pump design incorporating a ring oscillator with an odd number of inverters connected in series, a pumping circuit, and a feedback circuit to generate a boosted voltage with reduced variation, where the power voltage of the ring oscillator is inversely proportional to the boosted voltage, stabilizing the system and reducing power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a traditional charge pump driven by a constant frequency clock is used, then the charge pump can generate high voltage for internal circuits, but there is an excess of charge pump output and power consumption in a high-voltage state
Solution Approach 1:
The patent applies dynamics by making the clock frequency variable rather than constant. The clock signal frequency is dynamically adjusted based on the output voltage level - when the charge pump reaches high voltage state, the clock frequency is reduced or stopped, thereby reducing power consumption and excess output. This is achieved through a control mechanism that monitors output voltage and modulates the clock signal accordingly.
Solution Approach 2:
The patent implements feedback control where the output voltage of the charge pump is monitored and fed back to control the clock signal frequency. When the output voltage reaches a certain level, the feedback mechanism adjusts the clock frequency to prevent excessive output and reduce power consumption. This closed-loop control ensures optimal balance between power consumption and charge pump output.
2Reliability
If delay chains are used to separate the turn-on time of each charge pump core, then simultaneous conduction noise is avoided, but the delay chains are highly dependent on ambient temperature and operating voltage
Solution Approach 1:
The patent introduces a clock signal as an intermediary that coordinates the operation of multiple charge pump cores. Instead of using temperature-sensitive delay chains, a centralized clock signal distributes timing information to all cores, ensuring they operate in sequence without simultaneous conduction. This intermediary approach decouples the timing mechanism from direct dependence on temperature and voltage variations.
Solution Approach 2:
The clock signal serves multiple functions: it provides timing synchronization for all charge pump cores, acts as a control signal for sequential operation, and functions as a reference for the feedback mechanism. This multi-functional approach replaces the need for separate delay chains for each core, reducing overall temperature and voltage sensitivity while maintaining noise reduction benefits.
3Reliability
If delay chains are made insensitive to temperature, process and voltage, then the charge pump achieves its original purpose, but the design becomes complex
Solution Approach 1:
The centralized clock signal acts as an intermediary that provides temperature-insensitive timing control to all charge pump cores. Rather than making individual delay chains insensitive to temperature (which would require complex compensation circuits), the clock signal is designed to be stable across temperature variations, simplifying the overall design while achieving the same reliability goal.
Data Source
AI summary
A charge pump comprises a ring oscillator and a pumping circuit. The ring oscillator provides a plurality of oscillating clocks. The pumping circuit includes a plurality of pumping blocks coupled to each other for outputting a boosted voltage, and each pumping block is connected to a corresponding oscillating clock.