CN-122018614-A - Band gap reference circuit

Abstract

A bandgap reference circuit is provided that includes a PTAT voltage circuit proportional to absolute temperature configured to generate a PTAT voltage, and a bandgap voltage circuit including a diode configured to receive the PTAT voltage from the PTAT voltage circuit, and to combine the PTAT voltage with a diode voltage across the diode to output a bandgap reference voltage.

Inventors

• Arvind Sherigal

Assignees

• 恩智浦有限公司

Dates

Publication Date

20260512

Application Date

20251015

Priority Date

20241111

Claims (10)

1. 1. A bandgap reference circuit, comprising: a PTAT voltage circuit proportional to absolute temperature configured to generate a PTAT voltage, and A bandgap voltage circuit comprising a diode, the bandgap voltage circuit configured to: receiving the PTAT voltage from the PTAT voltage circuit, and The PTAT voltage is combined with a diode voltage across the diode to output a bandgap reference voltage.
2. 2. The bandgap reference circuit according to claim 1, wherein said bandgap voltage circuit comprises: A bandgap voltage node configured to output the bandgap reference voltage, and A tail voltage node configured to be set to the PTAT voltage, Wherein an anode of the diode is connected to the bandgap voltage node and a cathode of the diode is connected to the tail voltage node.
3. 3. The bandgap reference circuit according to claim 2, wherein said bandgap voltage circuit comprises: a regulating transistor having a source terminal coupled to a supply voltage node and a drain terminal connected to the bandgap voltage node; an input circuit coupled to the PTAT voltage circuit and configured to set the tail voltage node to the PTAT voltage, and A current mirror output transistor having a conductive channel connected between the tail voltage node and a reference voltage node.
4. 4. A bandgap reference circuit as claimed in claim 3, wherein said input circuit comprises: a first input transistor, wherein a source terminal of the first input transistor is connected to the power supply node and a drain terminal of the first input transistor is connected to a gate terminal of the regulating transistor, and A second input transistor, wherein a drain terminal of the second input transistor is connected to the gate terminal of the regulation transistor and a source terminal of the second input transistor is connected to the tail voltage node.
5. 5. The bandgap reference circuit of any of claims 2 to 4, comprising an output circuit connected between the bandgap voltage node and a reference node, wherein the output circuit is configured to provide a constant current through the output circuit from the bandgap voltage node to the reference node.
6. 6. The bandgap reference circuit of claim 5, wherein said output circuit comprises an output resistor circuit.
7. 7. The bandgap reference circuit of claim 5, wherein said output circuit comprises a current sink.
8. 8. The bandgap reference circuit of any of claims 5 to 7 when dependent on claim 3 or 4, wherein said current mirror output transistor is configured to pull a constant current through said regulation transistor, said constant current through said regulation transistor being equal to said constant current provided through said output circuit.
9. 9. The bandgap reference circuit of claim 8, wherein said bandgap reference circuit comprises an output current reference transistor configured to mirror said constant current from said regulation transistor to a constant current output.
10. 10. An automotive transceiver comprising a bandgap reference circuit according to any preceding claim.

Description

Band gap reference circuit Technical Field The present disclosure relates to a bandgap reference circuit. Background Bandgap reference circuits built with bipolar transistors are commonly used in the Brokaw or Banba configuration to build bandgap reference voltages. Bipolar transistors are known to create electromagnetic interference (EMI) problems because the collector is exposed to the substrate/handle wafer. To avoid bipolar, a simple PN diode is typically used in the Banba architecture to achieve a constant reference voltage/current. However, the use of PN diodes in the Banba architecture results in large area and high noise. Disclosure of Invention According to a first aspect of the present disclosure, there is provided a bandgap reference circuit comprising: a PTAT voltage circuit proportional to absolute temperature configured to generate a PTAT voltage, and A bandgap voltage circuit comprising a diode, the bandgap voltage circuit configured to: receiving the PTAT voltage from the PTAT voltage circuit, and The PTAT voltage is combined with a diode voltage across the diode to output a bandgap reference voltage. In one or more embodiments, the bandgap voltage circuit may include: A bandgap voltage node configured to output the bandgap reference voltage, and A tail voltage node configured to be set to the PTAT voltage, Wherein an anode of the diode is connected to the bandgap voltage node and a cathode of the diode is connected to the tail voltage node. In one or more embodiments, the bandgap voltage circuit may include: a regulating transistor having a source terminal coupled to a supply voltage node and a drain terminal connected to the bandgap voltage node; an input circuit coupled to the PTAT voltage circuit and configured to set the tail voltage node to the PTAT voltage, and A current mirror output transistor having a conductive channel connected between the tail voltage node and a reference voltage node. The PTAT voltage circuit is configured to generate the PTAT voltage from a supply voltage received at the supply voltage node, and In one or more embodiments, the input circuit may include: a first input transistor, wherein a source terminal of the first input transistor is connected to the power supply node and a drain terminal of the first input transistor is connected to a gate terminal of the regulating transistor, and A second input transistor, wherein a drain terminal of the second input transistor is connected to the gate terminal of the regulation transistor and a source terminal of the second input transistor is connected to the tail voltage node. The first input transistor and the second input transistor may form an output of a current mirror. The input circuit may mirror a PTAT current from the PTAT voltage circuit. The input circuit may mirror the PTAT voltage from the PTAT voltage circuit to the tail voltage node. The gate terminal of each of the first and second input transistors may be connected to a respective terminal of the PTAT voltage circuit. The regulation transistor, the diode, and the first and second input transistors may form a regulation loop. The regulation loop may regulate a current through the regulation transistor to regulate the bandgap reference voltage at the bandgap voltage node. The regulation loop may regulate the bandgap reference voltage to a sum of the PTAT voltage and the diode voltage. In one or more embodiments, the bandgap reference circuit may include an output circuit connected between the bandgap voltage node and a reference node, wherein the output circuit is configured to provide a constant current through the output circuit from the bandgap voltage node to the reference node. In one or more embodiments, the output circuit may include an output resistance circuit. The output resistor circuit may include a plurality of resistors. In one or more embodiments, wherein the output circuit may include a current sink. In one or more embodiments, the current mirror output transistor may be configured to pull a constant current through the regulation transistor equal to the constant current provided through the output circuit. The current mirror output transistor is configured to mirror a multiple of a PTAT current from the PTAT voltage circuit to provide the constant current through the regulation transistor. In one or more embodiments, the bandgap reference circuit may include an output current reference transistor configured to mirror the constant current from the regulating transistor to a constant current output. In one or more embodiments, the bandgap reference circuit may include a balanced current transistor, wherein: The source terminal of the balance current transistor is connected to the power supply voltage node, and The drain terminal of the balanced current transistor is connected to the bandgap voltage node. The balanced current transistor may mirror a PTAT current from the PTAT voltage circuit. The gate terminal of the balanced current transi