Integrated switch-mode power supply and linear regulator
View Patent ↗A power supply includes a switching voltage regulator, and a linear voltage regulator coupled electrically in series with the switching voltage regulator. The switching voltage regulator includes a first input for receiving a DC input signal, a semiconductor switching stage coupled to the first input and configured to provide a first DC voltage signal from the received DC input signal. The magnitude of the first DC voltage signal is less than the received DC input signal. The linear voltage regulator includes a semiconductor current pass stage coupled to the output of the semiconductor switching stage and configured to provide a constant second DC output voltage signal from the first DC voltage signal. The voltage regulators are implemented together within a common integrated circuit housing.
1. A power supply comprising:
a switching voltage regulator, the switching voltage regulator comprising a first input for receiving a DC input signal, and a semiconductor switching stage coupled to the first input and being configured to provide a first DC voltage signal from the received DC input signal; and
a linear voltage regulator coupled electrically in series with the switching voltage regulator, the linear voltage regulator comprising a semiconductor current pass stage coupled to an output of the switching voltage regulator and being configured to provide a constant second DC output voltage signal from the first DC voltage signal,
wherein the power supply is devoid of a voltage control loop between the linear voltage regulator and the switching voltage regulator.
2. The power supply of claim 1 wherein the semiconductor current pass stage is coupled to an output of the semiconductor switching stage.
3. The power supply of claim 1 wherein the switching voltage regulator is configured as a boost-type regulator.
4. The power supply according to claim 1 , wherein the voltage regulators are implemented together within a common integrated circuit housing.
5. The power supply according to claim 1 , wherein the switching voltage regulator is configured to maintain a magnitude of the first DC voltage signal at a voltage level sufficient for the linear voltage regulator to maintain a magnitude of the second DC output voltage signal within a predetermined range.
6. The power supply according to claim 5 , wherein the semiconductor current pass stage comprises a controlled current source, and a second feedback loop coupled to the controlled current source, the second feedback loop being configured to vary a magnitude of current from the current source based on a magnitude of the second DC output voltage signal.
7. The power supply according to claim 6 , wherein the controlled current source comprises a transistor, and the linear voltage regulator comprises a low dropout voltage regulator.
8. A mobile wireless communications device comprising:
an antenna;
a data processor;
an RF section coupled to the antenna and the data processor for the communication of data between the antenna and the data processor:
a battery for providing a DC input signal; and
a power supply coupled to the battery and the RF section for supplying power to the RF section from the DC input signal, the power supply including:
a switching voltage regulator, the switching voltage regulator comprising a first input for receiving the DC input signal and a semiconductor switching stage coupled to the battery and being configured to provide a first DC voltage signal from the received DC input signal; and
a linear voltage regulator coupled electrically in series with the switching voltage regulator, the linear voltage regulator comprising a semiconductor current pass stage coupled to an output of the switching voltage regulator and being configured to provide a constant second DC output voltage signal from the first DC voltage signal,
wherein the power supply is devoid of a voltage control loop between the linear voltage regulator and the switching voltage regulator.
9. The mobile wireless communications device of claim 8 wherein the semiconductor current pass stage is coupled to an output of the semiconductor switching stage.
10. The mobile wireless communications device of claim 8 wherein the switching voltage regulator is configured as a boost-type regulator.
11. The mobile wireless communications device according to claim 8 , wherein the switching voltage regulator is configured to maintain a magnitude of the first DC voltage signal at a voltage level sufficient for the linear voltage regulator to maintain a magnitude of the second DC output voltage signal within a predetermined range.
12. The mobile wireless communications device according to claim 11 , wherein the controlled current source comprises a transistor, and the linear voltage regulator comprises a low dropout voltage regulator.
13. A power supply comprising:
a switching voltage regulator, the switching voltage regulator comprising a first input for receiving a DC input signal, and a semiconductor switching stage coupled to the first input and being configured to provide a first DC voltage signal from the received DC input signal;
a linear voltage regulator coupled electrically in series with the switching voltage regulator, the linear voltage regulator comprising a semiconductor current pass stage coupled to an output of the switching voltage regulator and being configured to provide a constant second DC output voltage signal from the first DC voltage signal; and
a voltage controller disposed between the linear voltage regulator and the switching voltage regulator and configured to maintain a magnitude of the first DC voltage signal at a voltage level sufficient for the linear voltage regulator to maintain a magnitude of the second DC output voltage signal within a predetermined range.
14. The power supply of claim 13 wherein the semiconductor current pass stage is coupled to an output of the semiconductor switching stage.
15. The power supply of claim 13 wherein the switching voltage regulator is configured as a boost-type regulator.
16. The power supply according to claim 13 , wherein the voltage regulators and the voltage controller are implemented within a common integrated circuit housing.
17. The power supply according to claim 13 , wherein the voltage controller is configured to maintain the magnitude of the first DC voltage signal at a voltage that is greater than the magnitude of the second DC output voltage signal by an amount at least equal to a dropout voltage of the linear voltage regulator.
18. The power supply according to claim 17 , wherein the maintained voltage is equal to the magnitude of the second DC output voltage signal and a voltage drop across the linear voltage regulator.
19. The power supply according to claim 13 , wherein the semiconductor switching stage includes a semiconductor switch, a port coupled to the semiconductor switch for coupling to a resonant circuit, and a first feedback loop coupled to the semiconductor switch, the first feedback loop being configured to vary a conduction interval of the semiconductor switch based on the magnitude of the first DC voltage signal.
20. A mobile wireless communications device comprising:
an antenna;
a data processor;
an RF section coupled to the antenna and the data processor for the communication of data between the antenna and the data processor;
a battery for providing a DC input signal; and
a power supply coupled to the battery and the RF section for supplying power to the RF section from the DC input signal, the power supply including:
a switching voltage regulator, the switching voltage regulator comprising a first input for receiving the DC input signal and a semiconductor switching stage coupled to the battery and being configured to provide a first DC voltage signal from the received DC input signal;
a linear voltage regulator coupled electrically in series with the switching voltage regulator, the linear voltage regulator comprising a semiconductor current pass stage coupled to an output of the switching voltage regulator and being configured to provide a constant second DC output voltage signal from the first DC voltage signal; and
a voltage controller disposed between the linear voltage regulator and the switching voltage regulator and configured to maintain a magnitude of the first DC voltage signal at a voltage level sufficient for the linear voltage regulator to maintain a magnitude of the second DC output voltage signal within a predetermined range.
21. The mobile wireless communications device of claim 20 wherein the semiconductor current pass stage is coupled to an output of the semiconductor switching stage.
22. The mobile wireless communications device of claim 20 wherein the switching voltage regulator is configured as a boost-type regulator.
23. The mobile wireless communications device according to claim 20 , wherein the voltage controller is configured to maintain the magnitude of the first DC voltage signal at a voltage that is greater than the magnitude of the second DC output voltage signal by an amount at least equal to a dropout voltage of the linear voltage regulator.
24. The mobile wireless communications device according to claim 23 , wherein the maintained voltage is equal to the magnitude of the second DC output voltage signal and a voltage drop across the linear voltage regulator.
25. The mobile wireless communications device according to claim 20 , wherein the semiconductor switching stage includes a semiconductor switch, a port coupled to the semiconductor switch for coupling to a resonant circuit, and a first feedback loop coupled to the semiconductor switch, the first feedback loop being configured to vary a conduction interval of the semiconductor switch based on the magnitude of the first DC voltage signal.