Discontinuous mode DC-DC converter including a voltage-current conversion circuit for converting into current a difference between an output voltage and an input voltage of switches of the converter
원문보기
IPC분류정보
국가/구분
United States(US) Patent
등록
국제특허분류(IPC7판)
H02M-003/158
H02M-001/00
출원번호
US-0559326
(2014-12-03)
등록번호
US-9391520
(2016-07-12)
우선권정보
EP-13195405 (2013-12-03)
발명자
/ 주소
Saby, Jérôme
Theoduloz, Yves
출원인 / 주소
EM Microelectronic-Marin SA
대리인 / 주소
Oblon, McClelland, Maier & Neustadt, L.L.P.
인용정보
피인용 횟수 :
1인용 특허 :
4
초록▼
The DC-DC converter includes an inductor cooperating with a first switch and a second switch operating alternately, in order to supply an output voltage of higher, equal or lower level than the level of an input voltage. The converter includes a switching control unit for the switches for determinin
The DC-DC converter includes an inductor cooperating with a first switch and a second switch operating alternately, in order to supply an output voltage of higher, equal or lower level than the level of an input voltage. The converter includes a switching control unit for the switches for determining a first switching time for the first switch and a second switching time for the second switch. The switching control unit includes a voltage-current conversion circuit for converting into current a comparison voltage, which is the difference between the output voltage and the input voltage, a first current being supplied by the conversion circuit for charging a first capacitor to a first voltage threshold to determine the first switching time and a second current being supplied by the conversion circuit for charging a second capacitor to a second voltage threshold to determine the second switching time.
대표청구항▼
1. A DC-DC converter, comprising: an inductor as reactive component, at least a first switch connected to the inductor and controlled by a first control signal, and at least a second switch connected to the inductor and controlled by a second control signal, the first and second switches operating a
1. A DC-DC converter, comprising: an inductor as reactive component, at least a first switch connected to the inductor and controlled by a first control signal, and at least a second switch connected to the inductor and controlled by a second control signal, the first and second switches operating alternately to supply an output voltage of a higher or lower level than the level of an input voltage, the converter also including a switching control unit for the switches for determining a first switching time of the first switch during which an increasing current flows through the inductor, and a second switching time of the second switch during which a decreasing current flows through the inductor,wherein the switching control unit includes a voltage-current conversion circuit for converting into current a comparison voltage, which is the difference between the output voltage and the input voltage, a first current being supplied by the voltage-current conversion circuit for charging a first capacitor to a first voltage threshold to determine the first switching time and a second current being supplied by the voltage-current conversion circuit for charging a second capacitor to a second voltage threshold to determine the second switching time on the basis of the determination of the first switching time. 2. The DC-DC converter according to claim 1, wherein the voltage-current conversion circuit includes an amplifier-comparator, whose first input receives the difference between the output voltage and the input voltage, and whose second input is connected to a resistor, and wherein an output of the amplifier-comparator controls a current mirror, whose first branch is series connected to the resistance for determining a basic current to be mirrored in the current mirror to define a first current in a second branch and a second current in a third branch of the current mirror. 3. The DC-DC converter according to claim 2, wherein the difference between the output voltage and the input voltage is supplied to a negative input of the amplifier-comparator, and in that a node connecting the resistor to the first branch of the current mirror is connected to a positive input of the amplifier-comparator, the resistor being connected to an earth terminal. 4. The DC-DC converter according to claim 3, wherein the current mirror is formed of PMOS transistors arranged in parallel, a source of each transistor being connected to a positive voltage terminal, a gate of each transistor being connected to the output of the amplifier-comparator, in that a drain of at least a first PMOS transistor in the first branch is connected to the resistor and to the positive input of the amplifier-comparator, in that a drain of at least a second PMOS transistor is connected to the first capacitor to supply a first charging current, and in that a drain of at least a third PMOS transistor is connected to the second capacitor to supply a second charging current. 5. The DC-DC converter according to claim 2, wherein the basic current is identical to the first current, and in that the first voltage threshold is equal to the difference between the output voltage and the input voltage so that the first switching time of the first switch is determined by the resistive value of the resistor multiplied by the capacitance of the first capacitor. 6. The DC-DC converter according to claim 5, wherein the basic current is identical to the second current, in that the capacitance of the first capacitor is equal to the capacitance of the second capacitor and in that the second voltage threshold is equal to the input voltage so that the second switching time of the second switch is determined by the formula t2=t1·(Vin/(Vout−Vin)), where t1 is the first switching time, t2 is the second switching time, Vin is the input voltage and Vout is the output voltage. 7. The DC-DC converter according to claim 1, wherein the switching control unit includes a subtractor receiving the output voltage at a first input and the input voltage at a second input in order to supply an output signal, which is the difference between the output voltage and the input voltage. 8. The DC-DC converter according to claim 1, wherein in the switching control unit, a third switch is connected and placed in parallel to the first capacitor, the third switch being controlled by a third control signal supplied by a logic circuit of the converter, the third switch being in a closed state for discharging the first capacitor and in an open state for charging the first capacitor to determine the first switching time, and in that a fourth switch is connected and placed in parallel to the second capacitor, the fourth switch being controlled by a fourth control signal supplied by the logic circuit, the fourth switch being in a closed state for discharging the second capacitor and in an open state for charging the second capacitor to determine the second switching time. 9. The DC-DC converter according to claim 1, wherein the switching control unit includes a first comparator for comparing the first voltage threshold to the voltage across the first capacitor in charging phase to determine the first switching time of the first switch, a first comparison signal being supplied by the first comparator to control a logic circuit of the converter, in order to keep the first switch closed, when the voltage across the first capacitor is below the first voltage threshold and to open the first switch, when the voltage across the first capacitor is above the first voltage threshold. 10. The DC-DC converter according to claim 9, wherein the first voltage threshold is the difference between the output voltage and the input voltage. 11. The DC-DC converter according to claim 1, wherein the switching control unit includes a second comparator for comparing the second voltage threshold to the voltage across the second capacitor in charging phase to determine the second switching time of the second switch, a second comparison signal being supplied by the second comparator to control a logic circuit of the converter, in order to keep the second switch closed when the voltage across the second capacitor is below the second voltage threshold and to open the second switch when the voltage across the second capacitor is above the second voltage threshold. 12. The DC-DC converter according to claim 11, wherein the second voltage threshold is the input voltage. 13. The DC-DC converter according to claim 1, wherein the switching control unit includes a logic circuit, which is clocked by a clocking signal from an oscillator of the converter, so as to define each control cycle of the DC-DC converter, and which supplies the first and second control signals to the first and second switches. 14. A method of actuating a DC-DC converter according to claim 1, wherein, in each control cycle of the DC-DC converter, the method comprises: closing the first switch via the first control signal with the second switch in an open state, a first current being supplied by the voltage-current conversion circuit for charging the first capacitor to a first voltage threshold to determine the first switching time of the first switch, andat the end of the first switching time, closing the second switch via the second control signal with the first switch controlled to be opened, a second current being supplied by the voltage-current conversion circuit for charging the second capacitor to a second voltage threshold to determine the second switching time of the second switch on the basis of the determination of the first switching time. 15. The method of actuating a DC-DC converter according to claim 14, wherein the first capacitor is charged by the first current to determine the first switching time until the voltage across the first capacitor attains the first voltage threshold, which is the difference between the output voltage and the input voltage. 16. The method of actuating a DC-DC converter according to claim 14, wherein the second capacitor is charged by the second current to determine the second switching time until the voltage across the second capacitor attains the second voltage threshold, which is the input voltage.
연구과제 타임라인
LOADING...
LOADING...
LOADING...
LOADING...
LOADING...
이 특허에 인용된 특허 (4)
Tomiyoshi,Kenji, Apparatus and method for switching voltage regulation.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.