59results about How to "Reduce bias current" patented technology

The present invention relates to a timing system including an integrated circuit having an oscillator that provides both high and low frequency clock signals from a single high frequency crystal without the necessity of a tuning fork crystal. The low frequency signal is available for time-keeping applications, with low power consumption during “idle” periods. The high performance high frequency signal is available on demand for clock and frequency reference use. The oscillator of the present invention provides improved time-keeping accuracy, whilst size, cost and component count is reduced. Furthermore, phase noise and other critical parameters of the high frequency oscillator are not compromised. Shock vulnerability, a known problem for tuning fork crystals, is reduced.

The invention relates to an electronic device and a method for DC-DC conversion using a comparator for generating an output signal for driving a power switch of a switch mode DC-DC converter. The electronic device is configured to reduce a bias current of the comparator with a first slope in response to a decreasing load and to increase the bias current of the comparator with a second slope in response to an increasing load, wherein the second slope is steeper than the first slope.

The invention discloses a tera-hertz silica-based quadrupler and a frequency multiplier, belonging to the field of RFIC (Radio Frequency Integrated Circuit). The quadrupler comprises transistors (M1 and M2) and transmission lines (L1, L2 and L-1), wherein the drain ends of the transistors (M1 and M2) are respectively connected to an output port through the transmission lines (L1 and L2), source ends are connected with a ground line, grid ends are respectively connected with the signal input ends of an path (I) and the path (Q) of a baseband signal (f0); the transmission line (L-1) is connected between the output port and a power supply; and the length of the transmission lines (L1 and L2) are 1/4 of that of the corresponding wavelength of a signal (2f0), the length of the transmission line (L-1) is 1/4 of that of the corresponding wavelength of a signal (4f0). The multi-frequency multiplier comprises a 2n frequency multiplier (1), a 2n frequency multiplier (2) and a transmission line (L), wherein the output ports of the 2n frequency multiplier (1) and the 2n frequency multiplier (2) are connected to be used as the output port of a 2n+1 frequency multiplier, the transmission line (L) is connected between the output port of the 2n+1 frequency multiplier and the power supply, and the length of the transmission line (L) is 1/4 of that of the corresponding wavelength of a signal (2n+1f0). The tera-hertz silica-based quadrupler and the multi-frequency multiplier, provided by invention, have the advantages of high output frequency, pure frequency spectrum, low power consumption and easiness for integration.

The invention discloses a current type terahertz pyroelectricity detector reading circuit, and belongs to the field of terahertz detecting and imaging. The reading circuit comprises a current-voltage converter, a 50Hz trap circuit, a first-order lowpass filtering amplifying circuit and an electric potential raising module. Signals output by the terahertz pyroelectricity detector are input into the current-voltage converter so that the current signals can be converted into voltage signals; the signals output by the current-voltage converter are input into the 50Hz trap circuit so that power frequency interference can be eliminated; the signals output by the 50Hz trap circuit are input into the first-order lowpass filtering amplifying circuit so that the signals can be further amplified; the signals output by the first-order lowpass filtering amplifying circuit are input into the electric potential raising module so that a voltage can be raised and the voltage signals output by the circuit can be matched with a voltage required by a rear digital collecting circuit. The voltage signals output by the circuit are pure, and the circuit is suitable for collecting and outputting a weak current of the terahertz pyroelectricity detector.

The invention belongs to the technical field of integrated circuit and particularly relates to a temperature compensation current source having wide temperature scope and being compatible with CMOS (complementary metal-oxide-semiconductor transistor) technique, which comprises four NMOS (n-channel metal oxide semiconductor)tubes, three PMOS (p-channel metal oxide semiconductor) tubes, a compensation resistor and an operational amplifier, wherein the operational amplifier is a traditional two-stage miller compensation operational amplifier and has a biasing circuit; the high-gain operational amplifier can be used for ensuring that the voltages at difference input ends are the same; a main circuit of the temperature compensation current source is formed by the four NMOS tubes, three PMOS tubes and the compensation resistor; and by utilizing the resistance, the mobility of MOS tubes and different temperature coefficients of threshold voltages, the novel temperature compensation current source which is low in temperature coefficient, has small area, is fit for wide range of temperature change and is compatible with the standard CMOS technique, is realized.

The invention relates to the technical field of electronic communications, and discloses a voltage generation circuit and a voltage generation method which are used for generating band-gap reference voltage. The voltage generation circuit comprises a first circuit used for generating first voltage which is in direct proportion to temperature and a second circuit used for generating second voltage which is in inverse proportion to the temperature, wherein the first circuit and the second circuit are connected to enable the first voltage and the second voltage to be superposed, and therefore the band-gap reference voltage is provided; the first circuit is obtained by means of transistors. By means of the band-gap reference voltage generation method and circuit, the band-gap reference voltage is generated, the circuit power consumption can be reduced, and the chip area can be decreased.

The invention discloses an ultralow consumption current multiplexing mixer based on substrate bias. The mixer comprises the following parts: a transconductance grade consisting of a pair of NMOS (N-channel Metal Oxide Semiconductor) pipes and a pair of PMOS (P-channel Metal Oxide Semiconductor) pipes, a switch grade consisting of two pairs of NMOS pipes, and a load grade consisting of resistors. The transconductance grade of the mixer utilizes a self-bias complementary transconductance structure and forms a folding structure with the switch grade to greatly reduce voltage of a power supply; substrates of all the MOS pipes in a circuit are additionally provided with fixed bias voltage to reduce threshold voltage of the MOS pipe and realize the design of ultralow voltage ultralow power consumption; and through a current multiplexing technique, the noise performance of the circuit is modified, and the conversion gain and the linearity are improved. The ultralow consumption current multiplexing mixer based on the substrate bias, disclosed by the invention, can be applied to deep submicron radio frequency CMOS (Complementary Metal Oxide Semiconductor) integrated circuits and can be widely applied to electronic systems in the aerospace field.

The invention relates to a matching detection method and circuit of a content addressable memory cell. The matching detection method comprises the steps of: carrying out charging or charging control on a charge circuit of a first matching signal wire and a feedback control circuit of a second matching signal wire; when contents of an NOR memory cell are matched and a voltage difference exists between the matching signal wires, outputting a matching signal; and when the contents of the NOR memory cell are mismatched and no voltage difference exists between the matching signal wires, not outputting the matching signal. The matching detection method is simple and reliable, and has the advantages of reduction in additional offset voltage and offset current and further reduction in power consumption in comparison with the traditional matching detection method of the memory cell.

The invention provides a gate driving method and a gate driving device, so as to drive a gate of a liquid crystal display. The driving method comprises the steps that according to parts, which are away from the center of a panel, of the gate driving device, the gate driving device of a liquid crystal display panel is classified into a panel edge gate driving device, a panel middle driving device and a panel center gate driving device; and from the panel edge gate driving device to the panel center gate driving device, the bias current of an output operational amplifier of a gate drive IC gradually decreases. According to the invention, a gate drive IC output resistor and the gate drive IC output operational amplifier are designed; under the condition of normal panel drive display, the power consumption of the gate drive IC is minimized; and the power consumption of the liquid crystal panel is further reduced.

The invention provides a protection circuit of a power tube, the circuit comprises a bias branch connected to a grid electrode of the power tube and a clamping branch connected between a source electrode and a drain electrode of the power tube, the source electrode of the power tube is connected with an input end, the drain electrode of the power tube is connected with an output end, the bias branch is used for providing bias current, and the clamping branch is used for clamping the bias current. The output current of the power tube is limited by the bias current, and the clamping branch is used for reducing the bias current when the source-drain voltage of the power tube is greater than a source-drain clamping voltage threshold, so that the output current of the power tube is reduced, and the power tube enters a current-limiting protection mode to control the power. Thus, current limiting and clamping can be combined, the power of the power tube is limited, and the safety of the power tube is protected fundamentally.

According to the reference and operational amplifier integrated linear voltage regulator, a depletion tube is introduced, and the depletion tube reference is used as the reference and the first stage of the operational amplifier, so that the operational amplifier and the reference are integrated, a starting circuit is not needed, the circuit is very simple, and the circuit performance is greatly improved on the basis of realizing the circuit performance of the linear voltage regulator. The depletion reference is used as a reference and a first stage of the operational amplifier, so that the static power consumption of low-power application can be obviously improved, and the optimal combination of performance and cost is realized.

The invention discloses an on-chip RC oscillator circuit, and belongs to the technical field of integrated circuits. The on-chip RC oscillator circuit includes a low-power-consumption temperature compensation circuit, a charge and discharge control circuit, a comparator circuit, an RS flip flop, and a buffer. A first NMOS transistor, a first PMOS transistor, a fourth PMOS transistor, a third resistor and a second NMOS transistor in the low-power-consumption temperature compensation circuit form a loop for generating a bias current with a negative temperature coefficient. A second NMOS transistor, a second PMOS tube, a third PMOS transistor, a third NMOS transistor and a second resistor form a loop that generates a positive temperature coefficient current. The two loops implement a negativefeedback connection through the second NMOS transistor, and the first capacitor and the first resistor perform the miller compensation for a negative feedback loop to improve stability. The oscillator circuit only needs four current branches, and the positive and negative temperature coefficient current structure required for temperature compensation is very simple, and the power consumption is low. The first NMOS transistor, the second NMOS transistor and the third NMOS transistor operate at a sub-threshold section, achieving a smaller bias current and consuming less power.

The invention discloses a constant current loop, which comprises an EA (error amplifier) and a power supply, wherein one end of the EA is connected with one end of a current detection element, and the other end of the EA is connected with the other end of the current detection element through a reference generation element; one end of the power supply is grounded, and the other end of the power supply is connected with the source or drain of a metal oxide layer semiconductor field effect transistor; the drain or source of the metal oxide layer semiconductor field effect transistor is connected with the other end of the current detection element. According to the constant current loop, the EA is directly used for forming a negative feedback closed loop, and the whole loop has only one EA gain stage; the offset voltage and bias current of the whole loop are reduced, so that constant current is higher in accuracy; in addition, the structure of the loop is simplified, and the implementation cost is lowered.

The present invention provides an AC motor speed regulating circuit, which includes a motor power supply circuit composed of a first freewheeling module or a second freewheeling module, a rectifier module and a switch module to supply power to the AC motor, and the AC power supply is the first continuous current through the switch module. The conduction power supply of the current module or the second freewheeling module realizes the discharge of the induced electromotive force generated on the main winding of the AC motor through the first freewheeling module or the second freewheeling module, thereby ensuring the normal operation of the AC motor . Moreover, the first freewheeling module and the second freewheeling module are composite tube structures composed of two triodes respectively. When discharging the induced electromotive force generated by the AC motor when the switch module is closed, due to the composite structure of the triodes, it passes The bias current provided by the switch module to maintain the conduction of the above-mentioned freewheeling module is very small, so the bias power consumption provided by the switch module can be greatly reduced, the volume of this part of the circuit is saved, and the heat loss is reduced.