摘要:
A bandgap reference circuit for generating a reference voltage includes a transistor, a bias current source for generating a bias current, a proportional to absolute temperature (PTAT) current source for generating a PTAT current, a first resistor, and a second resistor. The transistor generates a base-emitter voltage that is divided at an output node through the first and second resistors. The first resistor couples between the collector of the transistor and the output node. The second resistor couples between the output node and ground. The bias current source supplies the bias current to the transistor and the PTAT current source supplies a PTAT current to output node 105. The reference voltage may be obtained at output node as a result of combining a portion of the base-emitter voltage, which has a negative temperature coefficient, with a PTAT voltage that is obtained by sensing a portion of the PTAT current over the second resistor.
摘要:
An exemplary method and circuit for temperature nonlinearity compensation and trimming of a voltage reference are configured to provide for two-point independent trimming of each of the curvature coefficients within the Taylor approximation curve. A voltage reference circuit is configured with a translinear circuit having an input current source. The translinear circuit comprises a translinear unit having a plurality of output currents corresponding to the curvature coefficients of the Taylor row approximation curve, with the output currents coupled to a control input terminal of the voltage reference. During trimming, at a first nominal temperature, the input current source is trimmed to a zero value, and each of the curvature terms of the Taylor approximation will be equal to zero value. At a second temperature the plurality of output currents of the translinear circuit can be measured to enable independent trimming of each of the curvature coefficients such that the output currents of the translinear circuit are made substantially equal to predetermined values. Thus, each of the coefficients of the Taylor approximation curve are independently trimmed to pass through zero at the first temperature and through the predetermined values at the second temperature without regard from one voltage reference circuit to another.
摘要:
A bandgap circuit for producing a constant current having a controllable temperature coefficient. A current mirror supplies first and second substantially identical currents to first and second bipolar transistors. A first resistor is connected across the emitters of the bipolar transistors. A second resistor connects one to the bipolar emitters to a common terminal where the current source currents are recombined and supplied to a common terminal of a power supply. The band gap voltage produced at the common base connections of the bipolar transistors have a voltage temperature coefficient which is controlled by the values of the resistors. A current source is coupled to receive the bandgap voltage and produces a current having a temperature coefficient corresponding to the voltage temperature coefficient of the bandgap voltage.
摘要:
A reference voltage source for an integrated circuit includes a first voltage reference that is adjustable, a second voltage reference, a differential sensing device to compare a voltage provided by the first voltage reference to a voltage provided by the second voltage reference, a controller to provide a trim control signal to the first voltage reference in response to an output of the differential sensing device for adjusting the first voltage reference and to provide a signal to power down the second voltage reference after the first voltage reference has been adjusted.
摘要:
A boost voltage circuit includes a plurality of N channel type MOS transistors connected between an input terminal and an output terminal in series, wherein one electrode of each of the N channel type MOS transistors is connected to each of external terminals to which a capacitor can be connected, to generate a boost voltage. A plurality of P channel type MOS transistors are respectively connected to each of the N channel type MOS transistors in parallel. Thereby, a boost voltage circuit with improved stability is provided so that the boost voltage circuit is started without increase of consumption current.
摘要:
A current generating circuit includes a first resistance inversely proportional current generator, a second resistance inversely proportional current generator, and a current subtractor. The first resistance inversely proportional current generator has a first resistance element, and generates a first current which is inversely proportional to resistance variation of the first resistance element. The second resistance inversely proportional current generator has second and third resistance elements of the same type as the first resistance element, and generates a second current which is inversely proportional to half of the resistance variation. The current subtractor subtracts the first current from the second current to output a constant current regardless of the resistance variation of the first to third resistance elements.
摘要:
The voltage generator includes the NPN transistor that flows a current corresponding to a voltage VOP output from the error detector. Furthermore, there is provided the current mirror circuit which includes two PNP transistors that flow currents which are multiples of the current that the NPN transistor flows. Furthermore, there are provided two resistors for generating a feedback voltage VFBK to the error detector from an output voltage VREG generated based on a current that the current mirror circuit flows.
摘要:
A high-speed current mirror and correction circuitry are provided to minimize current errors in short-channel MOS switched current mirrors. The current mirror supplies high current levels at high modulation speeds, while simultaneously exhibiting good output voltage compliance. The correction circuitry includes a buffer amplifier, current shaping circuit, and replica mirror section. The current shaping circuit is able to supply a differential reference current, to correct load current errors, in response to the replica mirror section matching the buffered load voltage.
摘要:
A reference voltage generator capable of stably generating a reference voltage irrespective of temperature variations is provided. The reference voltage generator includes a voltage bias unit having a plurality of resistors and a first group of transistors serially connected between a power supply voltage node and a ground voltage node, a reference voltage node connected to one of the plurality of resistors or transistors to produce a preliminary reference voltage; a voltage controller connected between the preliminary reference voltage node and the ground voltage node; a temperature compensator having a second group of transistors serially connected between the preliminary reference voltage node and a reference voltage node to produce a reference voltage; and a voltage compensator having a third group of transistors serially connected between the reference voltage node and the ground voltage node for controlling the reference voltage. The temperature compensator compensates for temperature variation and the voltage compensator maintains the reference voltage at a predetermined value regardless of the temperature variation. Thus, the reference voltage generator can generate a stable reference voltage.
摘要:
There is disclosed a reference current circuit capable of preventing an appearance of the effect of the Early voltage, operated from a low power supply voltage, and adapted to output a current having a positive or optional temperature characteristic. In this reference current circuit, by a self-biased method, a current of a current mirror circuit is set to be proportional or substantially inversely proportional to a temperature by first and second transistors constituting a non-linear current mirror circuit. A third transistor is provided. A current of the third transistor proportional to a third voltage between a control terminal and a current input terminal is set to be substantially inversely proportional to the temperature, and the currents of the current mirror circuit and the third transistor are weighted and added. Thus, an output current having a fixed temperature current is obtained.