Electronic circuit
View Patent ↗An electronic circuit is disclosed. The electronic circuit includes a bandgap circuit provided with first and second bipolar transistors that are coupled at a first node and a current mirror circuit provided with third and fourth transistors with respective control terminals coupled at a second node. The electronic circuit further includes a fifth transistor that is bipolar which is coupled to an output terminal of the third transistor where a base of the fifth transistor is coupled to a collector of the second transistor and a sixth transistor that is bipolar that is coupled to an output terminal of the fourth transistor with a base of the sixth transistor coupled to the first node. A control circuit controls a current provided to the bandgap circuit based on an output of the current mirror circuit. A reference voltage output terminal is provided between the control circuit and the bandgap circuit and outputs a reference voltage.
1. An electronic circuit comprising:
a bandgap circuit comprising a first bipolar transistor and a second bipolar transistor wherein the respective bases of the first bipolar transistor and the second bipolar transistor are coupled at a first node;
a current mirror circuit comprising a third transistor and a fourth transistor, wherein the respective control terminals of the third transistor and the fourth transistor are coupled at a second node, a fifth transistor, that is a bipolar transistor, coupled to an output terminal of the third transistor wherein a base of the fifth transistor is coupled to a collector of the second transistor, and a sixth transistor, that is a bipolar transistor, coupled to an output terminal of the fourth transistor wherein a base of the sixth transistor is coupled to the first node;
a control circuit that controls a current provided to the bandgap circuit based on an output of the current mirror circuit; and
a reference voltage output terminal provided between the control circuit and the bandgap circuit and outputting a reference voltage.
2. The electronic circuit according to claim 1 , wherein a ratio of an emitter area of the fifth transistor to an emitter area of the first transistor is equal to the ratio of an emitter area of the sixth transistor to an emitter area of the first transistor times a ratio of an output current of the third transistor to an output current of the fourth transistor.
3. The electronic circuit according to claim 2 , wherein the first transistor and the second transistor have base currents that are equal in magnitude.
4. The electronic circuit according to claim 3 , wherein the second transistor comprises a plurality of transistors that have the same configuration as that of the first transistor and are coupled in parallel.
5. The electronic circuit according to claim 1 , the electronic circuit further comprising:
a first resistor coupled to an emitter of the second transistor; and
a second resistor provided between the reference voltage output terminal and a collector of the first transistor,
wherein the collector of the first transistor is coupled to the first node.
6. The electronic circuit according to claim 5 , wherein a base-emitter voltage of the first transistor and a voltage across the second resistor have temperature coefficients of opposite polarity.
7. The electronic circuit according to claim 6 , wherein the temperature coefficient of the base-emitter voltage of the first transistor and the temperature coefficient of the voltage across the second resistor have the same absolute value.
8. The electronic circuit according to claim 1 , wherein the control circuit includes a seventh transistor with a control terminal coupled to the output of the current mirror circuit.
9. The electronic circuit according to claim 8 , wherein the seventh transistor is a normally-on transistor.
10. An electronic circuit comprising:
a bandgap circuit comprising a first bipolar transistor and a second bipolar transistor wherein the respective bases of the first bipolar transistor and the second bipolar transistor are coupled at a first node;
a current mirror circuit comprising a third transistor and a fourth transistor, that are bipolar transistors, wherein the respective control terminals of the third transistor and the fourth transistor are coupled at a second node, a fifth transistor, that is a bipolar transistor, coupled to an output terminal of the third transistor wherein a base of the fifth transistor is coupled to a collector of the second transistor, and a sixth transistor, that is a bipolar transistor, coupled to an output terminal of the fourth transistor wherein a base of the sixth transistor is coupled to the first node, wherein the collectors of the third and fourth transistor are output terminals;
a control circuit that controls a current provided to the bandgap circuit based on an output of the current mirror circuit; and
a reference voltage output terminal provided between the control circuit and the bandgap circuit and outputting a reference voltage.
11. The electronic circuit according to claim 10 , wherein a ratio of an emitter area of the fifth transistor to an emitter area of the first transistor is equal to the ratio of an emitter area of the sixth transistor to an emitter area of the first transistor times a ratio of an output current of the third transistor to an output current of the fourth transistor.
12. The electronic circuit according to claim 11 , wherein the first transistor and the second transistor have base currents that are equal in magnitude.
13. The electronic circuit according to claim 12 , wherein the second transistor comprises a plurality of transistors that have the same configuration as that of the first transistor and are coupled in parallel.
14. The electronic circuit according to claim 10 , the electronic circuit further comprising:
a first resistor coupled to an emitter of the second transistor; and
a second resistor provided between the reference voltage output terminal and a collector of the first transistor,
wherein the collector of the first transistor is coupled to the first node.
15. The electronic circuit according to claim 14 , wherein a base-emitter voltage of the first transistor and a voltage across the second resistor have temperature coefficients of opposite polarity.
16. The electronic circuit according to claim 15 , wherein the temperature coefficient of the base-emitter voltage of the first transistor and the temperature coefficient of the voltage across the second resistor have the same absolute value.
17. The electronic circuit according to claim 10 , wherein the control circuit includes a seventh transistor with a control terminal coupled to the output of the current mirror circuit.
18. The electronic circuit according to claim 17 , wherein the seventh transistor is a normally-on transistor.
19. An electronic system comprising:
data input circuitry;
data storage circuitry;
data processing circuitry; and
data output circuitry, wherein said electronic system comprises an electronic circuit comprising:
a bandgap circuit comprising a first bipolar transistor and a second bipolar transistor wherein the respective bases of the first bipolar transistor and the second bipolar transistor are coupled at a first node;
a current mirror circuit comprising a third transistor and a fourth transistor, wherein the respective control terminals of the third transistor and the fourth transistor are coupled at a second node, a fifth transistor, that is a bipolar transistor, coupled to an output terminal of the third transistor wherein a base of the fifth transistor is coupled to a collector of the second transistor, and a sixth transistor, that is a bipolar transistor, coupled to an output terminal of the fourth transistor wherein a base of the sixth transistor is coupled to the first node;
a control circuit that controls a current provided to the bandgap circuit based on an output of the current mirror circuit; and
a reference voltage output terminal provided between the control circuit and the bandgap circuit and outputting a reference voltage.
20. The electronic system according to claim 19 , wherein a ratio of an emitter area of the fifth transistor to an emitter area of the first transistor is equal to the ratio of an emitter area of the sixth transistor to an emitter area of the first transistor times a ratio of an output current of the third transistor to an output current of the fourth transistor.