On-Chip Clock Generator Using Transistor Timing for Stable Frequency
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Solution Overview
Problem
Existing clock signal generators in on-chip systems suffer from instability in clock frequency due to delays caused by static operating points and temperature drift, affecting the reliability and performance of the on-chip system.
Innovation Solution
A clock signal generator design that utilizes transistors controlled by a control signal generation circuit to alternately turn on and off, with frequency determined by the turn-on and turn-off times of the transistors, independent of comparator delays, and stabilized by capacitor charging and discharging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a comparator is used to generate clock signals, then the clock signal can be generated, but the delay between input and output of the comparator changes with temperature and static operating point, causing frequency instability
Solution Approach 1:
The patent removes the comparator from the clock signal generation circuit. Instead of using a comparator to generate the clock signal, the invention uses a ring oscillator composed of odd numbers of inverters, which eliminates the temperature-sensitive delay issues associated with comparators while maintaining the ability to generate stable clock signals.
Solution Approach 2:
The patent introduces a temperature compensation mechanism that dynamically adjusts the oscillation frequency based on temperature changes. By using a temperature compensation circuit that generates compensation signals in response to temperature variations, the system maintains frequency stability despite environmental changes.
2Reliability
If the clock signal generator is disposed inside the on-chip system, then the clock signal can be provided for the on-chip system, but the delay changes based on static operating point and temperature drift reduce frequency stability
Solution Approach 1:
The patent implements a feedback mechanism where the output of the ring oscillator is fed back to the input through a feedback circuit. This feedback loop, combined with temperature compensation, continuously adjusts the oscillation parameters to maintain stable frequency despite temperature variations and static operating point changes.
Data Source
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AI summary
A clock signal generator (100), an on-chip clock system, and a chip are provided. The clock signal generator (100) includes a first transistor (T1), a second transistor (T2), a flip-flop, and a power supply end. A first electrode of the first transistor (T1) and a first electrode of the second transistor (T2) are coupled to the power supply end, and a second electrode of the first transistor (T1) and a second electrode of the second transistor (T2) are coupled to a common ground (Gnd). A first input end of the flip-flop is coupled to the first electrode of the first transistor (T1), and a second input end of the flip-flop is coupled to the first electrode of the second transistor (T2). The clock signal generator (100) can make a frequency of an output clock signal more stable.