Abstract: The present application provides a single-ended to differential converter for converting a single-ended input to dual outputs. The converter comprises a band pass filter having an input node for coupling to the single-ended input, an output node, and a reference node, wherein the band pass filter is arranged to band pass filter the single ended input and provide the band pass filtered input signal to the output node as an output signal, an amplifier circuit accepting the output signal as an input and providing dual outputs, and a DC biasing circuit for generating a bias voltage and applying it to the reference node of the band pass filter. By presenting the bias voltage to the reference node of the band pass filter, a number of advantages including lower noise are achieved.

Abstract: Reference circuits are described. In particular reference circuits that use a plurality of cascaded proportional to absolute temperature, PTAT, cells are described. In the circuits disclosed, currents of the low current density arm of first PTAT cell are mirrored into the high current density arms of a second PTAT cell such that any deviation of current in the low current density arm of the first cell will be replicated as the current in the high current density arm of the second cell. In this way low noise circuits can be provided.

Abstract: Reference circuits are described. In particular reference circuits that use a plurality of cascaded proportional to absolute temperature, PTAT, cells are described. In the circuits disclosed, currents of the low current density arm of first PTAT cell are mirrored into the high current density arms of a second PTAT cell such that any deviation of current in the low current density arm of the first cell will be replicated as the current in the high current density arm of the second cell. In this way low noise circuits can be provided.

Abstract: In accordance with an embodiment, a proportional to absolute temperature (PTAT) circuit includes a first bipolar transistor having a collector coupled to a common node; a second bipolar transistor having a collector coupled to the common node; a MOSFET having a load path coupled between a base of the first bipolar transistor and a base of the second bipolar transistor; and an amplifier having a first input coupled to an emitter of the first bipolar transistor, a second input coupled to an emitter of the second bipolar transistor and an output coupled to a gate of the MOSFET.

Abstract: In accordance with an embodiment, a proportional to absolute temperature (PTAT) circuit includes a first bipolar transistor having a collector coupled to a common node; a second bipolar transistor having a collector coupled to the common node; a MOSFET having a load path coupled between a base of the first bipolar transistor and a base of the second bipolar transistor; and an amplifier having a first input coupled to an emitter of the first bipolar transistor, a second input coupled to an emitter of the second bipolar transistor and an output coupled to a gate of the MOSFET.

Abstract: The present disclosure relates to a PTAT voltage reference circuit and a temperature independent voltage reference circuit in which the effect of transistor base currents on the circuit output is compensated for. This is achieved by a pair of compensation resistors. The base current from one of the pair of transistors is used to increase the voltage drop across one of the compensation resistors. The base current from the other of the pair of transistors is used to decrease the voltage drop across another of the compensation resistors, by an equal amount. The compensation resistors are connected in series with the resistor which reflects the difference in base-emitter voltage (?VBE). The circuit output is measured across the series connected resistors. As such, the base currents are compensated for at the output.

Abstract: The present disclosure relates to a PTAT voltage reference circuit and a temperature independent voltage reference circuit in which the effect of transistor base currents on the circuit output is compensated for. This is achieved by a pair of compensation resistors. The base current from one of the pair of transistors is used to increase the voltage drop across one of the compensation resistors. The base current from the other of the pair of transistors is used to decrease the voltage drop across another of the compensation resistors, by an equal amount. The compensation resistors are connected in series with the resistor which reflects the difference in base-emitter voltage (?VBE). The circuit output is measured across the series connected resistors. As such, the base currents are compensated for at the output.

Abstract: Circuits for generating a PTAT voltage as a base-emitter voltage difference between a pair of bipolar transistors. The circuits may form unit cells in a cascading voltage reference circuit that increases the PTAT voltage with each subsequent stage. The bipolar transistors are controlled using a biasing arrangement that includes an MOS transistor connected to a current mirror that provides the base current for the bipolar transistors. A voltage reference is formed by combining a PTAT voltage and a CTAT voltage at the last stage. The voltage reference may be obtained from the voltage at an emitter of one of the bipolar transistors in the last stage.

Abstract: A bias current generators that may be implemented in low power environments is described. The current generator can be implemented without using resistors and may be used to generate reference currents and voltages. It may also be used to generate voltage references where the output of the circuit is to at least a first order temperature independent.

Abstract: The present disclosure relates to a method and apparatus for generating a voltage reference. More particularly the present disclosure relates to a methodology and circuitry configured to provide an output signal that combines a proportional to absolute temperature component with a complimentary to absolute temperature component to generate a stable output which is not temperature dependent.

Abstract: A proportional to absolute temperature (PTAT) circuit is provided. By judiciously combining circuit elements into two or more cell it is possible to effectively dump bias current into impedance resistive element of a first cell from other cells of the circuit. As a result the circuit as a whole can operate with smaller resistive elements and therefore occupy less area when implemented in silicon. It is also possible to reduce the supply current that is required for providing specific output currents or voltages.

Abstract: Early effects are intrinsically present in bipolar junction transistors (BJTs). Described are examples of complimentary to absolute temperature (CTAT) and proportional to absolute temperature (PTAT) cells that reduce errors associated with the Early effects that would otherwise be present.

Abstract: The present disclosure relates to a method and apparatus for generating a voltage reference. More particularly the present disclosure relates to a methodology and circuitry configured to provide an output signal that combines a proportional to absolute temperature component with a complimentary to absolute temperature component to generate a stable output which is not temperature dependent.

Abstract: A bias current generators that may be implemented in low power environments is described. The current generator can be implemented without using resistors and may be used to generate reference currents and voltages. It may also be used to generate voltage references where the output of the circuit is to at least a first order temperature independent.

Abstract: Circuits and method for providing voltage reference circuits that include low drift over time and lower operating voltages are provided. Generally, it is desirable that a reference circuit provide an accurate and precise reference over time. The voltage reference circuits described can provide for good long term stability, operation at lower voltages than prior designs, consistent output voltage with reduced variability due to process changes and mismatches, low noise in the reference voltage, and other advantages.

Abstract: Early effects are intrinsically present in bipolar junction transistors (BJTs). Described are examples of complimentary to absolute temperature (CTAT) and proportional to absolute temperature (PTAT) cells that reduce errors associated with the Early effects that would otherwise be present.

Abstract: A proportional to absolute temperature, PTAT, circuit is provided. By judiciously combining circuit elements it is possible to generate a voltage at an output node of the circuit that is temperature dependent. Such a PTAT circuit can be used as a temperature sensor or can be combined with other temperature dependent circuits to provide a voltage reference.

Abstract: Circuits for generating a PTAT voltage as a base-emitter voltage difference between a pair of bipolar transistors. The circuits may form unit cells in a cascading voltage reference circuit that increases the PTAT voltage with each subsequent stage. The bipolar transistors are controlled using a biasing arrangement that includes an MOS transistor connected to a current mirror that provides the base current for the bipolar transistors. A voltage reference is formed by combining a PTAT voltage and a CTAT voltage at the last stage. The voltage reference may be obtained from the voltage at an emitter of one of the bipolar transistors in the last stage.

Abstract: Circuits for generating a PTAT voltage as a base-emitter voltage difference between a pair of bipolar transistors. The circuits may form unit cells in a cascading voltage reference circuit that increases the PTAT voltage with each subsequent stage. The bipolar transistors are controlled using a biasing arrangement that includes an MOS transistor connected to a current mirror that provides the base current for the bipolar transistors. A voltage reference is formed by combining a PTAT voltage and a CTAT voltage at the last stage. The voltage reference may be obtained from the voltage at an emitter of one of the bipolar transistors in the last stage.

Abstract: The present disclosure relates to a method and apparatus for generating a voltage reference. More particularly the present disclosure relates to a methodology and circuitry configured to provide an output signal that combines a proportional to absolute temperature component with a complimentary to absolute temperature component to generate a stable output which is not temperature dependent.