Clock generator with temperature compensation and process error correction functions

Abstract

The invention provides a clock generator with temperature compensation and process error correction functions. The clock generator comprises a current mode band gap reference module, an annular oscillator module and a clock shaping module. A core circuit of the current mode band gap reference module is used for generating positive temperature coefficient current (IPTAT) and negative temperature coefficient current (ICTAT), and generating bias current by using a N-bit current mirror, the annular oscillator module a is used for generating an output signal with clock frequency information, and the clock shaping module is used for performing duty ratio adjustment and voltage peak adjustment on the output of the annular oscillator to form a final clock signal. The clock generator adjusts the proportionality coefficient of the positive temperature coefficient current (IPTAT) and the negative temperature coefficient current (ICTAT) and adjusts the N-bit value of the current mirror to adjust the adjustable range of the bias current Ibias necessary for the clock generator, and controls the magnitude of the access current so as to perform temperature compensation and process error correction on the clock signal.

Description

technical field [0001] The invention relates to the field of integrated circuits, in particular to a clock generator with process error correction and temperature compensation. Background technique [0002] All sequential circuit systems require a clock generator to produce an accurate clock signal that does not change significantly with the temperature process required by the system. Because the various characteristic values ​​of the transistors of the CMOS process will change significantly at different temperatures, such as the threshold voltage (Vth) will decrease significantly with the increase of temperature, etc., so even if the reference voltage or reference current provided to the clock generator does not change with temperature The variation of the threshold voltage (Vth) of the transistor of the CMOS process with temperature will also significantly affect the frequency of the clock signal. Moreover, chips located between different wafers or at different positions ...

AI Technical Summary

Problems solved by technology

Because the various characteristic values ​​of the transistors of the CMOS process will change significantly at different temperatures, such as the threshold voltage (Vth) will decrease significantly with the increase of temperature, etc., so even if the reference voltage or reference current provided to the clock generator does not change with temperature The change of the threshold voltage (Vth) of the transistor of the CMOS process with the temperature will also significantly affect the frequency of the clock signal

Moreover, chips located between different wafers or at different positions of the same wafer will have different degrees of process errors caused by processing errors, and this error will also directly affect the frequency of the clock signal

[0003] At present, although there are embodiments of temperature and process compensation for the clock generator, since the output after compensation is a voltage signal, the voltage needs to be converted into a current, which consumes a lot of power and requires additional circuit design.

Images