8results about How to "Lower Offset Voltage" patented technology

The invention discloses an oscillation circuit. The oscillating circuit comprises a charging and discharging module, an energy storage module, a self-zeroing comparison module and an output module; the self-return-to-zero comparison module comprises a storage unit and an output unit; the charging and discharging module is connected with the energy storage module, and the charging and discharging module is used for charging and discharging the energy storage module according to the power supply voltage, so that the energy storage module outputs a triangular wave signal; the storage unit is connected with a first threshold voltage, a second threshold voltage and an offset voltage of the output unit, and the output unit is used for outputting a comparison signal based on a comparison result of the triangular wave signal and the first threshold voltage when the feedback voltage is at a second level and outputting a comparison signal based on a comparison result of the triangular wave signal and the first threshold voltage when the feedback voltage is at a first level. Outputting a comparison signal based on a comparison result of the triangular wave signal and the second threshold voltage; and the output module is connected with the self-return-to-zero comparison module, the feedback voltage is accessed to the output module, and the output module is used for outputting an oscillation signal according to the comparison signal and the feedback voltage. According to the technical scheme, the reliability and the stability of the oscillation circuit are improved.

The disclosed embodiment provides a logarithmic conversion circuit and chip, in which the chopper circuit receives a DC input signal, performs a DC-to-AC process on the DC input signal, and generates an AC input signal; the conversion circuit receives an AC input signal, and performs amplification and AC-to-DC process on the AC input signal, and generates a DC output signal; the conversion circuit includes N cascaded amplifier circuits, and the first-stage amplifier circuit receives an AC input signal; the feedback circuit is connected between the output end of the j-stage amplifier circuit and the input end of the i-stage amplifier circuit, and is used to input a feedback signal to the input end of the i-stage amplifier circuit, wherein the feedback signal includes a DC portion and / or a low-frequency portion in the output signal of the j-stage amplifier circuit. The disclosed embodiment can suppress the offset voltage generated inside the amplifier circuit, which is beneficial for the circuit to achieve a large dynamic range.

The invention discloses a chopping operational amplifier for reducing switch artifacts by using an ORL. The chopping operational amplifier comprises a chopping module, a two-stage amplification module and an ORL module, the chopping module comprises a chopper I and a chopper II; the two-stage amplification module comprises a first-stage amplification module and an output-stage amplification module; the input end of the chopper I is used for acquiring an input signal, the output end of the chopper I is connected with the input end of the first-stage amplification module, and the chopper I is used for generating a modulation signal according to the input signal and transmitting the modulation signal to the first-stage amplification module; the output end of the first-stage amplification module is connected with the input end of the second chopper, and the first-stage amplification module is used for generating a first output signal according to the modulation signal and transmitting the first output signal to the second chopper. The output end of the chopper II is connected with the input end of the output stage amplification module, and is used for generating a demodulation signal according to the first output signal and transmitting the demodulation signal to the output stage amplification module, and on the basis of a pure chopping technology, an ORL is further expanded and added, so that the circuit realizes lower offset voltage and smaller switch artifacts.

The invention discloses an input current compensation circuit, an operational amplifier, a chip and an input current compensation method, and the input current compensation circuit comprises a current copying circuit and two compensation circuits. The current copying circuit is used for accessing a power supply voltage and a bias signal and generating a first current and a second current according to the bias signal and the power supply voltage; the compensating circuit is used for mirroring the first current so as to output a mirrored current of the first current to a first input end of the operational amplifier; the other compensation circuit is used for mirroring the second current so as to output the mirrored current of the second current to the second input end of the operational amplifier. According to the operational amplifier, the input current of the operational amplifier is sampled through the input current compensation circuit, and the compensation current input to the operational amplifier is generated, so that the input current of the operational amplifier is reduced or even eliminated, the input impedance of the operational amplifier is reduced, and the application range of the operational amplifier is widened.

The application relates to an analog integrated circuit technology field, and relates to a high-precision band gap reference source circuit based on digital trimming. In the band gap reference voltage source, a digital trimming resistor array, an adaptive current adjusting driver circuit and a low-offset amplifier circuit are integrated, so that temperature compensation of output voltage, strong band load capacity and low temperature coefficient of output voltage are realized. A temperature sensor outputs a control signal according to different temperatures, and sends the control signal to a digital control and signal processing module, and the digital control and signal processing module is connected with an I 2 C bus communication, and the I 2 C bus reads corresponding trimming codes from a nonvolatile memory and writes the trimming codes into internal digital registers. Then, a level shift circuit reads the trimming codes in the digital registers, and the trimming codes are converted from low voltage in the digital domain into high voltage in the analog domain. The high-voltage trimming codes are transmitted to a resistor array, and the resistor array trims resistors in the band gap reference voltage source according to the current temperature, so that low-offset voltage of the band gap reference voltage source is realized.

The application discloses a kind of based on chopping operational amplifier circuit, the positive and negative input of operational amplifier circuit is connected to operational amplifier unit through a pair of differential pair input, then is output through output stage, operational amplifier unit includes two gain boost operational amplifier, operational amplifier circuit also includes offset voltage adjustment current circuit, chopping switch is equipped at the positive and negative input of operational amplifier circuit, the input of gain boost operational amplifier and inside, gain boost gain boost folded cascode operational amplifier with chopping technology is used, including common-mode voltage control, while improving the output impedance and gain of cascode stage, the offset, drift and 1 / f noise of itself can be eliminated, offset voltage adjustment current circuit reduces the offset voltage caused by transistor size variation in production and manufacture, output stage uses DC bias voltage control circuit, both ensure that output tube is slightly on, improve the output response speed of operational amplifier, and can be controlled at lower static power consumption level.The application realizes effective zero drift technology by independent chopping circuit.

The invention discloses a manufacturing process of an SDB type silicon MEMS high-temperature pressure sensor, and relates to the technical field of pressure detection devices of micro electro mechanical systems, and the manufacturing process comprises the following steps: S1, preparing an SOI material based on a silicon substrate; s2, photoetching a resistor region, and carrying out ion implantation; s3, photoetching a corrosion protection area; s4, carrying out wet etching; s5, manufacturing a lead hole and a metal lead; step S6, metallization and passivation are carried out; and S7, photoetching a back corrosion region. According to the manufacturing process of the SDB type silicon MEMS high-temperature pressure sensor, the surface of the pressure sensitive resistor is not damaged, and the uniformity and consistency are good.

The invention provides a method for eliminating offset voltage to realize reference high-precision output voltage, and relates to a high-precision output voltage method. According to the method, a reference circuit comprises a starting circuit, a self-biasing circuit, an operational amplifier with a chopping structure, a low-pass filter and a band-gap reference module. The self-biased circuit ensures that follow-up circuits can obtain stable bias current and voltage, the operational amplifier with a chopping structure eliminates offset voltage through the chopping technology, the influence of the offset voltage on amplifier output is reduced, and the output of the amplifier is improved. The low-pass filter filters out the offset voltage modulated to the high frequency, and the band-gap reference module generates reference voltage which does not change along with the temperature. The influence of offset voltage on the operational amplifier is greatly reduced, the low-pass filter is introduced, offset voltage signals modulated to high frequency and high-frequency noise signals are eliminated, high-precision output of the operational amplifier is achieved, and therefore low-offset, high-precision and low-temperature-drift reference voltage output is guaranteed.