58results about How to "Reduce temperature drift coefficient" patented technology

The invention discloses an all-CMOS (Complementary Metal Oxide Semiconductor) reference voltage source with a high power supply rejection ratio, which comprises a reference voltage source. The reference voltage source comprises a starting circuit, a current source circuit and a temperature compensating circuit, wherein an output end of the starting circuit is connected with an input end of the current source circuit; an output end of the current source circuit is connected with an input end of the temperature compensating circuit; an output end of the temperature compensating circuit forms an output end of the whole reference voltage source. The working characteristic of an MOS transistor working in a sub-threshold region is utilized by the all-CMOS reference voltage source, a nanoampere-magnitude reference current is generated; power supply noise is rejected by adopting a cascode current mirror. In addition, the all-CMOS reference voltage source not only has the advantages that the chip area is small and the power consumption is low and is only nanowatt-magnitude, but also has the advantages that the all-CMOS reference voltage source has the high power supply rejection ratio, the temperature drift coefficient is low, and the line-voltage regulation is low; moreover, a resistor, a diode and a triode are not used; the all-CMOS reference voltage source is compatible with a standard CMOS process; the layout area is effectively reduced; the production cost is decreased.

Low temperature drift high power supply rejection ratio bandgap reference circuit based on exponential compensation, including pre-regulation module, pre-regulation start-up module, bandgap reference core module and bandgap reference core start-up module, the bandgap reference core module is used to generate reference voltage , the fifteenth PMOS tube with common source connection forms a βhelp structure, which avoids the problem of too small a value of β in the CMOS process, which causes excessive errors in the base current; at the same time, the high-order curvature of the reference voltage is compensated by the ninth resistor R9 The structure is embedded in the βhelp structure, which significantly reduces the temperature drift coefficient of the reference output voltage; the bandgap reference core startup module is used to make the bandgap reference core module break away from the degeneracy point; the pre-regulator module is used to generate a bandgap reference core module The local voltage supplied by the bandgap reference core start-up module, through the self-adaptive drive structure, not only ensures the driving capability of the pre-regulation structure but also effectively improves the power supply rejection ratio of the reference output voltage; the pre-regulation start-up module is used to make the pre-stabilization The compression module leaves the degeneracy point.

The invention relates to an interface circuit of a differential capacitance micro vibrating sensor. The interface circuit is composed of a power supply voltage stabilizing circuit, a square wave exciting circuit, a C-V conversion circuit, an amplification filter circuit and a micro vibrating sensor sensing element. The interface circuit is in a single-supply power supply mode; and diodes D1 and D2 and capacitors C4 and C5 are employed inside the interface circuit to supply power for internal devices. A square wave excitation signal is generated by an RC crystal oscillator and passes through aresistor Rs1; and then the square wave excitation signal is divided into two paths of signals that respectively pass through a capacitor Cn1 and a capacitor Cn2; and charging and discharging are carried out on sensitive capacitors Cs1 and Cs2. The C-V conversion circuit linearly converts a differential capacitor delta C into a single-voltage signal Vsense; and then amplification and filtering arecarried out on the single-voltage signal Vsense and then the processed signal is output. According to the invention, the principle is simple and there is no large-scale integrated chip; and cost is low as well as miniaturization and low power consumption are easy to realize. The design is flexible; and temperature compensation, zero adjustment, and positive and negative sensitivity adjustment andthe like can be respectively carried out. And precision of detection on a weak signal generated by the differential capacitance micro vibrating sensor is high; a noise level is low; and stability is good.