摘要:
A reference circuit includes: (a) a first reference circuit having a reference signal and a ΔVBE loop; and (b) a modification circuit using a first voltage to change a first current in the ΔVBE loop of the first reference circuit. In one embodiment, the reference circuit is a voltage reference circuit. In some embodiments, the reference circuit can include a bandgap core circuit, which adds a VBE and a multiplied ΔVBE, so that the output voltage of the reference circuit is a bandgap voltage. The reference circuit also can also include a modification circuit, which uses the output voltage (i.e. the reference signal) of the bandgap core circuit to change a current in the ΔVBE loop. The ΔVBE loop can be the portion of the circuit involved in generating the ΔVBE voltage. Other embodiments are disclosed in this application.
摘要:
A voltage translator circuit generates a predetermined output voltage (e.g. one half of the supply voltage) in response to a predetermined input voltage. A pair of matched field effect transistors are coupled in series between first and second sources of supply voltage. The gate of the load transistor is coupled to a reference voltage, and the gate of the drive transistor is coupled to a source of input voltage. When both transistors are subject to the same operating conditions (at a predetermined input voltage level), their effective resistances become equal and the supply voltage is divided in half. The circuit does not depend for its operation upon precise threshold voltages of the devices as long as the devices are matched.
摘要:
A circuit that develops a current having a predetermined temperature coefficient includes a pair of transistors which are supplied equal collector currents but which are operated at different current densities to produce a difference voltage between the emitters thereof that has a predetermined temperature coefficient. A third transistor is biased to sink a collector current the value of which is set by the ratio of the difference voltage to the value of a first resistor which is coupled between the collector and base of the third transistor. A second resistor can be coupled between the base and emitter of the third transistor to an output of the circuit whereby the current flowing from the output has a net temperature coefficient that is determined by the ratio of the value of the first resistor to the value of the second resistor.
摘要:
A thermal shut-down circuit is provided that is monolithically integrated in a power BIMOS process wherein a vertical power PNP output transistor comprises a P-type substrate as a collector. The circuit compensates for vertical currents injected from the P-substrate into lateral transistors. A first PNP transistor has an emitter connected to a first resistor and conducts a first current. A second PNP transistor has an emitter connected to a second resistor and conducts a second current. A third resistor has one terminal coupled to the emitter of the second transistor. A fourth resistor is coupled in series with an output means, the combination thereof being coupled in parallel with the second and third resistors.
摘要:
A variable temperature coefficient level shifter includes a circuit which generates a voltage V.sub.BE having a negative temperature coefficient and a voltage .DELTA.V.sub.BE having a positive temperature coefficient. A control current is generated by placing a first resistor between V.sub.BE and ground and a second resistor between .DELTA.V.sub.BE and ground. Each of these currents forms a component of the control current which then has some net temperature coefficient. By properly scaling the resistors the control current may have any desired temperature coefficient between 2800 ppm and 3000 ppm. Once the temperature coefficient is set, a third resistor is provided through which the control current flows. The amplitude of the shift is then selected by selecting the value of resistor R.sub.S.
摘要:
A DC-DC converter (100) includes a switching transistor (M0) connecting an input power terminal (VIN) to an inductor (114) that is also connected to an output power terminal (VOUT), a synchronous rectification transistor (M1) connected to a junction node (113) between the inductor (114) and the switching transistor (M0), and a synchronous rectifier control circuit (200) with an integration capacitor (226) having a voltage that is charged and discharged by first and second current sources (210, 220) to track the charging and discharging of the inductor current, thereby generating a synchronous rectifier control signal (SR) that is applied to the synchronous rectification transistor to discharge the inductor current to zero.
摘要:
An amplifier output stage with minimum circuitry and optimum performance for providing a SAT-to-SAT output voltage signal at an output terminal. The amplifier output stage includes a first transistor having a collector coupled to the output terminal for sourcing current thereto, a base coupled to a first supply voltage terminal, and an emitter coupled to the first supply voltage terminal. A second transistor having a collector coupled to the output terminal for sinking current thereat, a base, and an emitter coupled to a second supply voltage terminal. A third transistor having a collector, a base coupled to the base of the second transistor, and an emitter coupled to the second supply voltage terminal by a first resistor. A fourth transistor having a collector coupled to the first supply voltage terminal, a base coupled to an input terminal, and an emitter coupled to the base of the third transistor. A fifth transistor having a collector coupled to the base of the first transistor, a base coupled to the collector of the third transistor, and an emitter coupled to the second supply voltage terminal and a sixth transistor having a collector coupled to the first supply voltage terminal, a base coupled to the first supply voltage terminal and to the second supply voltage terminal, and an emitter coupled to the base of the fifth transistor.
摘要:
A circuit is provided which comprises a push-pull switching stage responsive to applied control signals for alternately establishing high and low output voltage levels at an output of the circuit responsive to control signals which are derived from an applied input logic signal and which is disabled in response to the control signals being disabled for providing a high output impedance at the output. The circuit includes circuitry responsive to an applied disable signal for disabling the control signals while enabling further circuitry, the latter providing a transient current path to improve the transition from the high voltage output level to the high output impedance condition while establishing a pseudo high output impedance at the output of the circuit until the push-pull stage is disabled.
摘要:
An integrated current amplifier circuit combining bipolar and MOS technologies provides accurate current gain over a wide voltage supply range. The amplifier circuit includes a current source for providing first and second currents and first and second resistive circuits coupled to the current source for sinking the respective currents supplied therefrom. A feedback transistor connected between the current source and an output of the amplifier circuit provides current feedback to the first resistive circuit to establish the current gain action of the amplifier circuit which becomes a ratio of two resistors times an input current supplied to the second resistive circuit. The ratio of the two resistors can be accurately controlled thereby controlling the current gain of the amplifier circuit. Additionally, an active turn-off circuit requiring no standby bias current is provided to ensure that the feedback transistor is non-conducting when the amplifier is in an off state.
摘要:
A correction circuit (12) for providing an error correction voltage for a voltage reference (11). The voltage reference (11) provides a reference voltage within a predetermined temperature range. The voltage reference prior to correction has a peak magnitude at a temperature T.sub.0 within the predetermined temperature range. A first circuit (13) generates a correction current. Zero current is provided by the first circuit (13) at T.sub.0. A second circuit (14) receives the correction current and provides an output current that is uni-directional or of the same sense above and below T.sub.0. [Means responsive to t] The output current of the second circuit (14) generates a voltage across a resistor (28) that is [combined] added to the reference voltage above and below T.sub.0.