TW201832454A - Dc-dc converting apparatus - Google Patents

Abstract

A DC-DC converting apparatus including a multi-phase controller and power channels is disclosed. Each power channel includes a first capacitor, a second capacitor, an output unit, a converting unit, a first inductor, a second inductor and a first switch ~ a fourth switch. The first capacitor and the second capacitor are coupled between an input voltage and ground. The first switch and the second switch are coupled between input voltage and ground. The converting unit has a first terminal coupled between the first switch and the second switch, a second terminal coupled between the first capacitor and the second capacitor, a third terminal coupled between third switch and the first inductor, and a fourth terminal coupled between the fourth switch and the second inductor. In a timing control, when the multi-phase controller conducts the first switch and the fourth switch, the second switch and the third switch are switched off.

Description

   DC to DC conversion device   

The present invention relates to power conversion, and more particularly to a DC-to-DC conversion device.

Generally speaking, in the field of network equipment or automotive electronics, a DC-to-DC conversion device is often used to convert high voltage to low voltage. Please refer to FIG. 1, the conventional DC-to-DC conversion device 1 generally uses a two-stage architecture of a voltage regulator PRM and a transformer VTM to convert an input voltage of 48 volts into an output voltage of 1 volt for supply to the processor PSR.

However, the conventional DC-to-DC conversion device 1 still has the following two shortcomings to be overcome in practical application:

(1) The lack of a current balance control loop makes it difficult to effectively improve the current efficiency when connected in parallel.

(2) Since the transformer VTM has no transient response capability, once a transient occurs, the control unit MCU can only send a control signal Scom to control the voltage regulator PRM output voltage to provide the required voltage during the transient. Power changes.

In view of this, the present invention provides a DC-to-DC conversion device to solve the problems mentioned in the prior art.

A preferred embodiment of the present invention is a DC-to-DC conversion device. In this embodiment, the DC-to-DC conversion device includes a multi-phase controller and multiple power channels. Multiple power channels are respectively coupled to the multi-phase controller. Each power channel includes a first capacitor, a second capacitor, an output unit, a conversion unit, a first inductor, a second inductor, a first switch, a second switch, a third switch, and a fourth switch. The first capacitor is coupled to the input voltage. The second capacitor is connected in series to the first capacitor, and one terminal of the second capacitor is coupled to the ground terminal. The conversion unit has a first end, a second end, a third end, and a fourth end. The first end and the second end are on the primary side, and the third end and the fourth end are on the secondary side. The first inductor is coupled between the third terminal and the output unit. The second inductor is coupled between the fourth terminal and the output unit, and one terminal of the second inductor is coupled between the first inductor and the output unit. The first switch is coupled to the input voltage and the first capacitor. The second switch is connected to the first switch in series, and is coupled to the second capacitor and the ground terminal. The third switch is coupled between the third terminal and the first inductor, and one terminal of the third switch is coupled to the output unit. The fourth switch is connected to the third switch in series, and one terminal of the fourth switch is coupled between the fourth terminal and the second inductor. The first terminal is coupled between the first switch and the second switch, and the second terminal is coupled between the first capacitor and the second capacitor. The multi-phase controller is respectively coupled to the first switch, the second switch, the third switch and the fourth switch. In the sequence control, when the first switch and the fourth switch are turned on by the multi-phase controller, the second switch and the third switch are turned off.

In one embodiment of the present invention, the multi-phase controller provides a first pulse width modulation signal to control the operations of the first switch and the third switch.

In one embodiment of the present invention, the multi-phase controller provides a second pulse width modulation signal to control the operation of the second switch and the fourth switch.

In one embodiment of the present invention, the multi-phase controller provides a first pulse width modulation signal to control the operation of the first switch and the third switch, and the multi-phase controller provides a second pulse width modulation signal to control the second switch and the third switch With the operation of the four switches, the phase difference between the first PWM signal and the second PWM signal is 180 degrees.

In an embodiment of the present invention, the DC-to-DC conversion device further includes a first current sensing unit respectively coupled between the third switch and the multi-phase controller and between the fourth switch and the multi-phase controller.

In an embodiment of the present invention, the first current sensing unit includes a first resistor and a second resistor, the first resistor is coupled between the third switch and the multi-phase controller and the second resistor is coupled to the fourth switch And multi-phase controller.

In an embodiment of the present invention, the DC-to-DC conversion device further includes a second current sensing unit, which is respectively coupled to the multi-phase controller, two ends of the first inductor, and two ends of the second inductor.

In an embodiment of the present invention, the second current sensing unit includes four resistors, the four resistors are respectively coupled to both ends of the first inductor and the two ends of the second inductor, and the four resistors are coupled to the multi-phase Controller.

In one embodiment of the present invention, the output voltage of the DC-to-DC conversion device is less than 4% of the input voltage.

In an embodiment of the present invention, the output unit includes an output capacitor and an output resistor, and the output capacitor and the output resistor are connected in parallel between the output voltage and the ground terminal of the DC-to-DC conversion device.

Another preferred embodiment according to the present invention is a DC-to-DC converter. In this embodiment, the DC-to-DC conversion device includes a multi-phase controller and multiple power channels. Each channel includes a pair of input switches, a pair of input capacitors, a pair of output switches, an output unit, a first inductor, a second inductor, and a transformer. The pair of input switches includes a first switch and a second switch connected in series. The pair of input capacitors includes a first input capacitor and a second input capacitor connected in series. The pair of output switches includes a third switch and a fourth switch connected in series. One terminal of the output unit is coupled between the third switch and the fourth switch. The first inductor is coupled between the third switch and the output unit. The second inductor is coupled between the fourth switch and the output unit, and one end of the second inductor is coupled between the first inductor and the output unit. The primary side of the transformer is coupled between the first switch and the second switch and between the first input capacitor and the second input capacitor. The secondary side of the transformer is coupled between the third switch and the first inductor. And is coupled between the fourth switch and the second inductor. The multi-phase controller is respectively coupled to the pair of input switches and the pair of output switches, and the multi-phase controller provides two pulse-modulated clock signals with different phases to each power channel.

Another preferred embodiment of the present invention is a DC-to-DC conversion device. In this embodiment, the DC-to-DC conversion device includes multiple power channels and a multi-phase controller. Each channel includes a pair of input switches, a pair of input capacitors, a pair of output switches, an output unit, a transformer, and a first current sensing unit. The pair of input switches includes a first switch and a second switch connected in series. The pair of input capacitors includes a first input capacitor and a second input capacitor connected in series. The pair of output switches includes a third switch and a fourth switch connected in series. One terminal of the output unit is coupled between the third switch and the fourth switch. The primary side of the transformer is coupled between the first switch and the second switch, and the secondary side of the transformer is coupled to the third switch. The first current sensing unit is coupled to the third switch and the fourth switch, respectively. The multi-phase controller is coupled to the pair of input switches, the pair of output switches and the first current sensing unit. The multi-phase controller includes a current balancing circuit and a time signal generating unit. The current balancing circuit is coupled to the first current sensing unit of each channel, and the current balancing circuit provides a current balancing signal to the time signal generating unit.

Compared with the prior art, the DC-DC conversion device of the present invention has the following advantages:

(1) A single-stage isolated DC-DC converter architecture is used, which can save one stage compared with the two-stage architecture used in the prior art, so it can save costs and reduce the occupied chip area.

(2) Multi-phase pulse-width modulation can be directly performed according to the load behavior, so it can effectively improve the ability and speed of transient response.

(3) The cycle can be controlled separately according to the current sensing signals sensed at both ends of the secondary side of the transformer, so as to achieve the current balance function.

The advantages and spirit of the present invention can be further understood through the following detailed description of the invention and the accompanying drawings.

1‧‧‧DC to DC conversion device

PRM‧‧‧Voltage Regulator

VTM‧‧‧Transformer

PSR‧‧‧Processor

MCU‧‧‧ Controller

I _FB ‧‧‧Current feedback signal

V _FB ‧‧‧ Voltage feedback signal

Scom‧‧‧Control signal

SVID‧‧‧Power Management Protocol

MPC‧‧‧Multi-Phase Controller

CH1‧‧‧first power channel

CH2‧‧‧Second power channel

Q1 ~ Q8‧‧‧First switch ~ Eighth switch

C1 ~ C4‧‧‧First capacitor ~ Fourth capacitor

L1 ~ L4‧‧‧First inductor ~ Fourth inductor

C‧‧‧Capacitor

R‧‧‧ resistance

R1 ~ R4‧‧‧First resistance ~ Fourth resistance

T1 ~ T2‧‧‧ Conversion Unit

E1 ~ E4‧‧‧First end ~ Fourth end

SEN1‧‧‧first current sensing unit

SEN2‧‧‧Second current sensing unit

OUT‧‧‧ DC-to-DC converter output

OU‧‧‧Output unit

Co‧‧‧ output capacitor

RL‧‧‧Output resistance

Vin‧‧‧ input voltage

Vout‧‧‧Output voltage

Iout‧‧‧Output current

NOT‧‧‧Reverse

IL1 ~ IL2‧‧‧First inductor current ~ Second inductor current

PWM1 ~ PWM2‧‧‧First pulse width modulation signal ~ Second pulse width modulation signal

FB‧‧‧ feedback signal

ISEN1‧‧‧First current sensing signal

ISEN3‧‧‧Second current sensing signal

CSP‧‧‧The third current sensing signal

CSN‧‧‧ Fourth current sensing signal

HD1 ~ HD2‧‧‧First high voltage driver ~ Second high voltage driver

LD1 ~ LD2‧‧‧First low voltage driver ~ Second low voltage driver

VFB‧‧‧Feedback voltage

t ₀ 、 t ₁ ~ t ₅ ‧‧‧start time, first time ~ fifth time

△ T1 ~ △ T4‧‧‧First time zone ~ Fourth time zone

Ts‧‧‧ cycle

Vgs (Q1) ‧‧‧The gate-source voltage of the first switch

Vgs (Q2) ‧‧‧ Gate-source voltage of the second switch

V _NP (T1) ‧‧‧ Winding voltage of the conversion unit

PGND, SGND‧‧‧ ground terminal

TSG‧‧‧Time signal generating unit

CBC‧‧‧Current balance circuit

EA‧‧‧ Error Amplifier

CR1 ~ CR2‧‧‧ Comparator

RAMP1 ~ RAMP2‧‧‧ Ramp signal

S _CB ‧‧‧ Current balance signal

S _EA ‧‧‧ Error Amplified Signal

REF‧‧‧Reference signal

+, -‧‧‧ Input

FIG. 1 shows a schematic diagram of a conventional DC-to-DC converter using a two-stage architecture.

FIG. 2 is a schematic diagram illustrating a first current sensing unit of a DC-to-DC conversion device according to an embodiment of the present invention including a first resistor and a second resistor.

FIG. 3 is a schematic diagram illustrating that the second current sensing unit of the DC-to-DC conversion device according to another embodiment of the present invention includes four resistors.

FIG. 4 is a schematic diagram of a multi-phase controller in a DC-to-DC conversion device coupled to a first power channel and a second power channel, respectively.

FIG. 5 illustrates timing diagrams of the gate-source voltage of the first switch, the gate-source voltage of the second switch, the winding voltage of the conversion unit, the first inductor current, the second inductor current, and the output current, respectively.

FIGS. 6A to 6D are schematic diagrams illustrating the operation of the DC-to-DC conversion device in the first time zone to the fourth time zone in a cycle.

FIG. 7 illustrates an embodiment of the multi-phase controller in FIG. 2.

FIG. 8 illustrates an embodiment of the multi-phase controller in FIG. 3.

Reference will now be made in detail to the exemplary embodiments of the present invention, and examples of the exemplary embodiments will be described in the accompanying drawings. The same or similar referenced elements / components are used in the drawings and embodiments to represent the same or similar parts.

A preferred embodiment of the present invention is a DC-to-DC conversion device. In this embodiment, the DC-to-DC conversion device may include a multi-phase controller and multiple power channels, and the multi-phase controller is respectively coupled to the power channels and provides two pulse-modulated clock signals of different phases to Each power channel controls the operation of each power channel. The DC-to-DC conversion device is used to convert an input voltage (Vin) into an output voltage (Vout). For example, in one embodiment, the DC-to-DC conversion device can convert a 48-volt input voltage (Vin) to 0.6 volts to 1.5 volts. Output voltage (Vout). In the embodiment of the present invention, the DC-to-DC conversion device can make its output voltage (Vout) less than 4% of the input voltage (Vin) it receives, but it is not limited thereto. In one embodiment, the DC-to-DC conversion device can also convert an input voltage (Vin) of 48 volts into an output voltage (Vout) of 3.3 volts or 5 volts. In another embodiment, the DC-to-DC conversion device can also convert an input voltage (Vin) of 48 volts into an output voltage (Vout) of 12 volts.

Please refer to FIG. 2, which illustrates a schematic diagram of the DC-to-DC conversion device in this embodiment. As shown in FIG. 2, the multi-phase controller MPC is coupled to the first power channel CH1. The first power channel CH1 includes a first capacitor C1, a second capacitor C2, an output unit OU, a conversion unit T1, a first inductor L1, a second inductor L2, a first switch Q1, a second switch Q2, a third switch Q3, and a first Four switches Q4. In one embodiment of the present invention, the conversion unit T1 is a transformer. The first capacitor C1 and the second capacitor C2 connected in series on the high-voltage side (primary side) of the conversion unit T1 are input capacitors, and the first switch Q1 and the second switch Q2 connected in series are input switches; The third switch Q3 and the fourth switch Q4 connected in series on the low-voltage side (secondary side) are output switches.

The multi-phase controller MPC is coupled to the first switch Q1, the second switch Q2, the third switch Q3, and the fourth switch Q4, respectively. The multi-phase controller MPC can provide two different-phase pulse modulation clock signals to the first power channel CH1. For example, the multi-phase controller MPC provides the first pulse width modulation signal PWM1 to the first switch Q1 and the first The gates of the three switches Q3 are used to control the operations of the first switch Q1 and the third switch Q3. The multi-phase controller MPC provides the second pulse width modulation signal PWM2 to the gates of the second switch Q2 and the fourth switch Q4 to control the operation of the second switch Q2 and the fourth switch Q4. The first pulse width modulation signal PWM1 provided by the multi-phase controller MPC can generate a complementary signal to the gate of the third switch Q3 through the back-gate NOT; the second pulse width modulation signal PWM2 provided by the multi-phase controller MPC can be transmitted The anti-NOT generates a complementary signal to the gate of the fourth switch Q4.

In the timing control of the DC-to-DC conversion device in this embodiment, when the multi-phase controller MPC controls the first switch Q1 and the fourth switch Q4 to be turned on, the second switch Q2 and the third switch Q3 are turned off; otherwise, when the When the phase controller MPC controls the second switch Q2 and the third switch Q3 to be turned on, the first switch Q1 and the fourth switch Q4 are turned off.

In practical applications, the phase difference between the first PWM signal PWM1 and the second PWM signal PWM2 is 180 degrees.

The conversion unit T1 has a first terminal E1, a second terminal E2, a third terminal E3, and a fourth terminal E4. The first end E1 and the second end E2 are primary sides, and the third end E3 and the fourth end E4 are secondary sides. The first terminal E1 is coupled between the first switch Q1 and the second switch Q2. The second terminal E2 is coupled between the first capacitor C1 and the second capacitor C2. The third terminal E3 is coupled between the third switch Q3 and the first inductor L1. The fourth terminal E4 is coupled between the fourth switch Q4 and the second inductor L2.

The first capacitor C1 is coupled to the input voltage Vin. The second capacitor C2 is connected in series to the first capacitor C1, and one terminal of the second capacitor C2 is coupled to the ground terminal. The first inductor L1 is coupled between the third terminal E3 and the output unit OU. The second inductor L2 is coupled between the fourth terminal E4 and the output unit OU, and one terminal of the second inductor L2 is coupled between the first inductor L1 and the output unit OU. The first inductor current IL1 flows through the first inductor L1 and the second inductor current IL2 flows through the second inductor L2.

The first switch Q1 is coupled to the input voltage Vin and the first capacitor C1. The second switch Q2 is connected to the first switch Q1 in series, and the second switch Q2 is coupled to the second capacitor C2 and the ground terminal. The third switch Q3 is coupled between the third terminal E3 and the first inductor L1, and one terminal of the third switch Q3 is coupled to the output unit OU. The fourth switch Q4 is connected in series with the third switch Q3, and one terminal of the fourth switch Q4 is coupled between the fourth terminal E4 and the second inductor L2.

The output current Iout flows through the output unit OU to generate an output voltage Vout. The output unit OU may include an output capacitor Co and an output resistor R _L. The output capacitor Co and the output resistor R _L are connected in parallel between the output voltage Vout and the ground terminal. One end of the output capacitor Co is coupled to the first inductor L1 and the other end is coupled between the third switch Q3 and the fourth switch Q4. One end of the output resistor R _L is coupled to the first inductor L1 and the other end is coupled between the third switch Q3 and the fourth switch Q4.

In addition, the third resistor R3 and the fourth resistor R4 are connected in series between the output voltage Vout and the ground, and the multi-phase controller MPC is coupled between the third resistor R3 and the fourth resistor R4 and from the third resistor R3. A feedback signal FB is received with the fourth resistor R4. In this embodiment, the feedback signal FB is a divided voltage signal after the third resistor R3 and the fourth resistor R4 divide the output voltage Vout.

In the embodiment of FIG. 2, the DC-to-DC conversion device further includes a first current sensing unit SEN1, which includes a first resistor R1 and a second resistor R2. The first resistor R1 is coupled between the third switch Q3 and the multi-phase controller MPC, and the second resistor R2 is coupled between the fourth switch Q4 and the multi-phase controller MPC. A third terminal E3 located on the secondary side of the conversion unit T1 is coupled between the first resistor R1 and the third switch Q3. A fourth terminal E4 located on the secondary side of the conversion unit T1 is coupled between the second resistor R2 and the four switches Q4. The multi-phase controller MPC receives the first current sensing signal ISEN1 and the second current sensing signal ISEN3 from the first resistor R1 and the second resistor R2, respectively, to obtain the third end E3 located on the secondary side of the conversion unit T1. And the current magnitude of the fourth terminal E4, and respectively controlling the periods according to the first current sensing signal ISEN1 and the second current sensing signal ISEN3, so as to achieve the function of current balance.

Referring to FIG. 3, in another embodiment, the DC-to-DC conversion device further includes a second current sensing unit SEN2, which may include four resistors R, and one end of the four resistors R is respectively coupled to the first inductor L1. The two ends of the second inductor L2 and the two ends of the second inductor L2 are coupled to the multi-phase controller MPC. The multi-phase controller MPC receives the third current sensing signal CSP and the fourth current sensing signal CSN from the four resistors R to obtain the first inductor current IL1 and the first inductor current L1 and the second inductor L2 respectively. The second inductor current IL2 is used to determine whether an over-current phenomenon has occurred, so as to provide an over-current protection (OCP) function in a timely manner.

Referring to FIG. 4, in another embodiment, the multi-phase controller MPC is coupled to the first power channel CH1 and the second power channel CH2 respectively. The multi-phase controller MPC is coupled to the gates of the first switch Q1 and the second switch Q2 on the high-voltage side (primary side) in the first power channel CH1 through the first high-voltage driver HD1; the multi-phase controller MPC passes the first low-voltage The driver LD1 is coupled to the gates of the third switch Q3 and the fourth switch Q4 on the low-voltage side (secondary side) in the first power channel CH1.

The multi-phase controller MPC can provide the first pulse width modulation signal PWM1 and the second pulse width modulation signal PWM2 to the first high-voltage driver HD1, and the first high-voltage driver HD1 transmits the first pulse width modulation signal PWM1 and the first The two-pulse-width modulation signal PWM2 goes to the gates of the first switch Q1 and the second switch Q2 to control the operations of the first switch Q1 and the second switch Q2, respectively. The multi-phase controller MPC can also provide the first pulse width modulation signal PWM1 and the second pulse width modulation signal PWM2 to the first low-voltage driver LD1, and the first low-voltage driver LD1 transmits the second pulse width modulation signals PWM2 and The first PWM signal PWM1 to the gates of the third switch Q3 and the fourth switch Q4 are used to control the operations of the second switch Q3 and the fourth switch Q4, respectively.

Similarly, the multi-phase controller MPC is coupled to the gates of the fifth switch Q5 and the sixth switch Q6 on the high-voltage side (primary side) in the second power channel CH2 through the second high-voltage driver HD2; the multi-phase controller MPC passes The second low-voltage driver LD2 is coupled to the gates of the seventh switch Q7 and the eighth switch Q8 on the low-voltage side (secondary side) in the second power channel CH2.

In practical applications, the multi-phase controller MPC can be further coupled to the third power source channel to the fourth power source channel (not shown), or even more power source channels, and can be analogized according to the above, so it will not be repeated here. In addition, the multi-phase controller MPC provides two pulse width modulation signals for each power channel. If the multi-phase controller MPC is coupled to four power channels, the multi-phase controller MPC provides eight pulse width modulation signals to the aforementioned four power channels. The phase difference between each PWM signal is 45 degrees (45 degrees = 360 degrees / number of PWM signals). In the example of four power channels, the multi-phase controller MPC provides a first pulse width modulation signal and a fifth width modulation signal to the first power channel, wherein the first pulse width modulation signal and the fifth width modulation signal The phase difference is 180 degrees.

Next, please refer to FIGS. 5 and 6A to 6D at the same time. FIG. 5 illustrates timing diagrams of the gate-source voltage of the first switch, the gate-source voltage of the second switch, the winding voltage of the conversion unit, the first inductor current, the second inductor current, and the output current, respectively; FIG. 6A to 6D are schematic diagrams showing the operation of the DC-to-DC conversion device in the first time zone to the fourth time zone in a cycle, respectively.

In the first time section ΔT1, that is, from the start time t ₀ to the first time t ₁ , the multi-phase controller MPC controls the first switch Q1 and the fourth switch Q4 to be turned on and controls the second switch Q2 and the third Switch Q3 is closed. It can be seen from FIG. 6A that the current on the high-voltage side (primary side) of the conversion unit T1 flows in sequence through the first switch Q1, the first terminal E1, the second terminal E2, the second capacitor C2 to the ground terminal PGND of the conversion unit T1, The current on the low-voltage side (secondary side) of the conversion unit T1 flows in sequence through the fourth terminal E4, the third terminal E3, the first inductor L1, the output resistor R _L , the fourth switch Q4, the first Two inductors L2 and output capacitor Co. It can be seen from FIG. 5 that the first inductor current IL1 flowing through the first inductor L1 increases linearly and the second inductor current IL2 flowing through the second inductor L2 decreases linearly, because the absolute value of the slope of the first inductor current IL1 linearly increases Greater than the absolute value of the slope of the second inductor current IL2 linearly decreasing, the output current Iout obtained by adding the two will increase linearly.

In the second time section ΔT2, that is, from the first time t ₁ to the second time t ₂ , the multi-phase controller MPC controls the first switch Q1 and the fourth switch Q4 to be closed and controls the second switch Q2 and the first switch Three switches Q3 are closed. It can be seen from FIG. 6B that there is no current on the high-voltage side (primary side) of the conversion unit T1, and the current on the low-voltage side (secondary side) of the conversion unit T1 flows in sequence through the third switch Q3, the first inductor L1, and the output The resistor R _L , the fourth switch Q4, the second inductor L2 and the output capacitor Co. It can be seen from FIG. 5 that the first inductor current IL1 flowing through the first inductor L1 and the second inductor current IL2 flowing through the second inductor L2 both decrease linearly, so that the output current Iout obtained by adding the two also decreases linearly. .

In the third time zone ΔT3, that is, from the second time t ₂ to the third time t ₃ , the multi-phase controller MPC controls the second switch Q2 and the third switch Q3 to be turned on and controls the first switch Q1 and the fourth Switch Q4 is closed. It can be seen from FIG. 6C that the input current located on the high-voltage side (primary side) of the conversion unit T1 flows in sequence through the first capacitor C1, the second terminal E2 of the conversion unit T1, the first terminal E1, the second switch Q2, and the ground terminal PGND. The current on the low-voltage side (secondary side) of the conversion unit T1 flows through the first inductor L1, the output resistance R _L , the third switch Q3, the third terminal E3, the fourth terminal E4, and The second inductor L2 and the output capacitor Co. It can be seen from FIG. 5 that the first inductor current IL1 flowing through the first inductor L1 decreases linearly and the second inductor current IL2 flowing through the second inductor L2 increases linearly, because the absolute value of the slope of the second inductor current IL2 increases linearly It is larger than the absolute value of the slope of the linear decrease of the first inductor current IL1. Therefore, the output current Iout obtained by adding the two will increase linearly.

In practical applications, since the absolute value of the slope of the linear increase of the second inductor current IL2 in the third time section ΔT3 may be equal to the absolute value of the slope of the linear increase of the first inductor current IL1 in the first time section ΔT1, and The absolute value of the slope of the linear decrease of the first inductor current IL1 in the third time section ΔT3 may be equal to the absolute value of the slope of the linear decrease of the second inductor current IL2 in the first time section ΔT1, so that the first time zone The slope of the linear increase of the output current Iout in the section ΔT1 is equal to the slope of the linear increase of the output current Iout in the third time section △ T3, thereby effectively improving the stability of the output current Iout.

In a fourth time period △ T4, i.e., from the third time t ₃ to a fourth time t _4, a first multi-phase controller MPC control switch Q1 and the fourth switch Q4 are turned off and the second switch Q2 and the second Three switches Q3 are closed. It can be known from FIG. 6D that there is no current on the high-voltage side (primary side) of the conversion unit T1, and the current on the low-voltage side (secondary side) of the conversion unit T1 flows in sequence through the third switch Q3, the first inductor L1, and the output The resistor R _L , the fourth switch Q4, the second inductor L2 and the output capacitor Co. It can be seen from FIG. 5 that the first inductor current IL1 flowing through the first inductor L1 and the second inductor current IL2 flowing through the second inductor L2 both decrease linearly, so that the output current Iout obtained by adding the two also decreases linearly. .

In practical applications, since the first inductor current IL1 and the second inductor current IL2 in the fourth time section ΔT4 linearly decrease in slope, the absolute value of the slope can be equal to the first inductor current IL1 and the first inductor current IL2 in the second time section ΔT2. The absolute value of the slope of the linear decrease of the inductor current IL2 can make the slope of the linear decrease of the output current Iout in the second time section △ T2 equal to the slope of the linear decrease of the output current Iout in the fourth time section △ T4, thereby effectively Improve the stability of the output current Iout.

Another preferred embodiment according to the present invention is also a DC-to-DC conversion device. In this embodiment, the DC-to-DC conversion device includes a plurality of power channels and a multi-phase controller, and the multi-phase controller is respectively coupled to the power channels and controls the operations of the power channels.

Please refer to FIG. 2 and FIG. 7 at the same time. FIG. 7 is a detailed structural diagram of an embodiment of the multi-phase controller MPC in FIG. 2. It can be known from FIG. 2 and FIG. 7 that the first power channel CH1 includes a pair of input switches Q1 to Q2, a pair of input capacitors C1 to C2, a pair of output switches Q3 to Q4, an output unit OU, a transformer T1, a first inductor L1, and Second inductor L2. The multi-phase controller MPC is coupled to the pair of input switches Q1 to Q2 and the pair of output switches Q3 to Q4, respectively. The multi-phase controller MPC includes an error amplifier EA, a plurality of comparators CR1 to CR2, a current balance circuit CBC, and a time signal generating unit TSG. The output terminals of the error amplifier EA are respectively coupled to the input terminals + of the comparators CR1 to CR2. The output terminals of the comparators CR1 to CR2 are all coupled to the time signal generating unit TSG. The current balancing circuit CBC is coupled to the time signal generating unit TSG.

In this embodiment, the DC-to-DC conversion device may include a first current sensing unit SEN1, which may include a first resistor R1 and a second resistor R2. The first resistor R1 is coupled between the third switch Q3 and the multi-phase controller MPC, and the second resistor R2 is coupled between the fourth switch Q4 and the multi-phase controller MPC. In addition, the DC-to-DC conversion device further includes a feedback unit, which may include a third resistor R3 and a fourth resistor R4, and the third resistor R3 and the fourth resistor R4 are connected in series to the output terminal OUT and the ground terminal of the DC-to-DC conversion device. And the multi-phase controller MPC is coupled between the third resistor R3 and the fourth resistor R4.

The input terminal of the error amplifier EA is coupled between the third resistor R3 and the fourth resistor R4 in the feedback unit and receives the feedback signal FB from between the third resistor R3 and the fourth resistor R4. The input terminal of the error amplifier EA + receives the reference signal REF. The current balancing circuit CBC is respectively coupled to the first resistor R1 and the second resistor R2 in the first current sensing unit SEN1 of the first channel CH1 and receives the first current sensing signal ISEN1 and the second current sensing signal ISEN2, and The current balancing circuit CBC provides a current balancing signal S _CB to the time signal generating unit TSG. The input terminals + of the comparators CR1 to CR2 respectively receive error amplification signals S _EA and the input terminals of the comparators CR1 to CR2-respectively receive ramp signals RAMP1 and RAMP2. The output ends of the comparators CR1 to CR2 respectively output the comparison results to the time signal generating unit TSG, and the time signal generating unit TSG outputs the first according to the comparison results output by the comparators CR1 to CR2 and the current balance signal S _CB . The pulse width modulation signals PWM1 to the gates of the first switch Q1 and the third switch Q3 are used to control the operation of the first switch Q1 and the third switch Q3, and the second pulse width modulation signals PWM2 to the second switch Q2 and the third switch are provided. The gates of the four switches Q4 control the operations of the second switch Q2 and the fourth switch Q4.

Please refer to FIG. 3 and FIG. 8 at the same time. FIG. 8 is a detailed structural diagram of an embodiment of the multi-phase controller MPC in FIG. 3. It can be known from FIG. 3 and FIG. 8 that the first power channel CH1 includes a pair of input switches Q1 to Q2, a pair of input capacitors C1 to C2, a pair of output switches Q3 to Q4, an output unit OU, a transformer T1, a first inductor L1, and Second inductor L2. The multi-phase controller MPC is coupled to the pair of input switches Q1 to Q2 and the pair of output switches Q3 to Q4, respectively. The multi-phase controller MPC includes an error amplifier EA, a plurality of comparators CR1 to CR2, a current balance circuit CBC, and a time signal generating unit TSG. The output terminals of the error amplifier EA are respectively coupled to the input terminals + of the comparators CR1 to CR2. The output terminals of the comparators CR1 to CR2 are all coupled to the time signal generating unit TSG. The current balancing circuit CBC is coupled to the time signal generating unit TSG.

In this embodiment, the DC-to-DC conversion device may include a second current sensing unit SEN2, and the second current sensing unit SEN2 may include four resistors R. The four resistors R are respectively coupled to both ends of the first inductor L1 and the second inductor L2, and the four resistors R are all coupled to the multi-phase controller MPC. The current balancing circuit CBC of the multi-phase controller MPC receives the third current sensing signal CSP and the fourth current sensing signal CSN from the four resistors R to obtain the first current flowing through the first inductor L1 and the second inductor L2, respectively. An inductor current IL1 and a second inductor current IL2 are used to determine whether an over-current phenomenon occurs. The current balancing circuit CBC provides a current balancing signal S _CB to the time signal generating unit TSG. The time signal generating unit TSG outputs the first pulse width modulation signal PWM1 to the gates of the first switch Q1 and the third switch Q3 according to the comparison results output by the comparators CR1 to CR2 and the current balance signal S _CB to control the first The operation of the switches Q1 and the third switch Q3, and the provision of the second pulse width modulation signal PWM2 to the gates of the second switch Q2 and the fourth switch Q4 to control the operations of the second switch Q2 and the fourth switch Q4, so as to provide timely Over current protection function.

Although the above two embodiments only describe the operation of the multi-phase controller MPC coupling and controlling the first power channel CH1, in addition to coupling and controlling the first power channel CH1, the multi-phase controller MPC can actually be coupled at the same time. Connect and control the second power channel CH2, and even the multi-phase controller MPC can be coupled to and control eight power channels at the same time. As for the actual operation situation, it can be deduced by analogy with the above embodiment, so it will not be repeated here.

In addition, in practical applications, the number of comparators in the above-mentioned multi-phase controller MPC and the number of external wiring of the current balancing circuit CBC need to correspond to the number of pulse width modulation signals output by the time signal generating unit TSG. For example, if the time signal generating unit TSG outputs four PWM signals, the multi-phase controller MPC needs to include four comparators and the current balancing circuit CBC needs four wires to the outside. The rest can be deduced by analogy. This will not be repeated here.

Compared with the prior art, the DC-DC conversion device of the present invention has the following advantages:

(1) The single-stage isolated DC-to-DC converter architecture is used, which can save one stage compared with the two-stage architecture used in the prior art, so it can save costs and reduce the occupied chip area.

(2) Multi-phase pulse width modulation can be directly performed according to the load behavior, so it can effectively improve the ability and speed of transient response.

(3) Cycles can be controlled separately according to the current sensing signals sensed at both ends of the secondary side of the transformer to achieve the function of current balance.

With the above detailed description of the preferred embodiments, it is hoped that the features and spirit of the present invention can be more clearly described, and the scope of the present invention is not limited by the preferred embodiments disclosed above. On the contrary, the intention is to cover various changes and equivalent arrangements within the scope of the patents to be applied for in the present invention.

Claims (15)

    A DC-to-DC conversion device includes: a multi-phase controller; and a plurality of power channels respectively coupled to the multi-phase controller. Each power channel includes: a first capacitor coupled to an input voltage; a second A capacitor connected in series to the first capacitor, and one terminal of the second capacitor is coupled to a ground terminal; an output unit; a conversion unit having a first terminal, a second terminal, a third terminal, and a fourth terminal Wherein the first end and the second end are located on the primary side, and the third end and the fourth end are located on the secondary side; a first inductor is coupled between the third end and the output unit; a first Two inductors are coupled between the fourth terminal and the output unit, and one terminal of the second inductor is coupled between the first inductor and the output unit; a first switch is coupled between the input voltage and the output unit. A first capacitor; a second switch connected in series with the first switch and coupled to the second capacitor and the ground terminal; a third switch coupled between the third terminal and the first inductor; and One terminal of the third switch is coupled to the output unit; and a fourth switch is connected to the third switch in series. And one terminal of the fourth switch is coupled between the fourth terminal and the second inductor; wherein the first terminal is coupled between the first switch and the second switch, and the second terminal is coupled between Between the first capacitor and the second capacitor; wherein the multi-phase controller is respectively coupled to the first switch, the second switch, the third switch and the fourth switch; and in a timing control, When the multi-phase controller controls the first switch and the fourth switch to be turned on, the second switch and the third switch are turned off.         The DC-to-DC conversion device according to item 1 of the patent application scope, wherein the multi-phase controller provides a first pulse width modulation signal to control the operation of the first switch and the third switch.         The DC-to-DC conversion device described in item 1 of the patent application scope, wherein the multi-phase controller provides a second pulse width modulation signal to control the operation of the second switch and the fourth switch.         The DC-to-DC conversion device according to item 1 of the patent application scope, wherein the multi-phase controller provides a first pulse width modulation signal to control the operation of the first switch and the third switch, and the multi-phase controller provides A second pulse width modulation signal controls the operation of the second switch and the fourth switch. The phase difference between the first pulse width modulation signal and the second pulse width modulation signal is 180 degrees.         The DC-to-DC conversion device described in item 1 of the scope of the patent application, further includes: a first current sensing unit respectively coupled between the third switch and the multi-phase controller and the fourth switch and the Between multiphase controllers.         The DC-to-DC conversion device according to item 5 of the scope of patent application, wherein the first current sensing unit includes a first resistor and a second resistor, and the first resistor is coupled to the third switch and the multi-phase The controller and the second resistor are coupled between the fourth switch and the multi-phase controller.         The DC-to-DC conversion device described in item 1 of the patent application scope further includes: a second current sensing unit coupled to the multi-phase controller, two ends of the first inductor, and two of the second inductor, respectively. end.         The DC-to-DC conversion device according to item 7 of the scope of patent application, wherein the second current sensing unit includes four resistors, and the four resistors are respectively coupled to both ends of the first inductor and the second inductor. Both ends, and the four resistors are coupled to the multi-phase controller.         The DC-to-DC conversion device described in item 1 of the scope of patent application, wherein an output voltage of one of the DC-to-DC conversion devices is less than 4% of the input voltage.         The DC-to-DC conversion device according to item 1 of the patent application scope, wherein the output unit includes an output capacitor and an output resistance, and the output capacitor and the output resistance are connected in parallel with one of the output voltages of the DC-DC conversion device and Between the ground terminals.         A DC-to-DC conversion device includes: a multi-phase controller; and a plurality of power channels, each power channel includes: a pair of input switches, including a first switch and a second switch connected in series; a pair of input capacitors Including a first input capacitor and a second input capacitor connected in series; a pair of output switches including a third switch and a fourth switch connected in series; an output unit having one end coupled to the third switch and Between the fourth switch; a first inductor coupled between the third switch and the output unit; a second inductor coupled between the fourth switch and the output unit; and the second inductor One terminal is coupled between the first inductor and the output unit; and a transformer whose primary side is respectively coupled between the first switch and the second switch and is coupled between the first input capacitor and the first switch. Between two input capacitors, the secondary side of the transformer is respectively coupled between the third switch and the first inductor and between the fourth switch and the second inductor; wherein the multi-phase controller is respectively Coupled to the pair of input switches and the pair of inputs Switch, and the multi-phase controller are provided two different phases of the pulse modulated clock signal to each of the power supply passage.         A DC-to-DC conversion device includes a plurality of power channels, each of which includes: a pair of input switches including a first switch and a second switch connected in series; a pair of input capacitors including a first connected in series An input capacitor and a second input capacitor; a pair of output switches including a third switch and a fourth switch connected in series; an output unit having one end coupled between the third switch and the fourth switch; A transformer having a primary side coupled between the first switch and the second switch, and a secondary side coupled to the third switch; and a first current sensing unit respectively coupled to the third switch and The fourth switch; and a multi-phase controller coupled to the pair of input switches, the pair of output switches, and the first current sensing unit, wherein the multi-phase controller includes a current balancing circuit and a time signal generating unit, The current balancing circuit is coupled to the first current sensing unit of each channel, and the current balancing circuit provides a current balancing signal to the time signal generating unit.         The DC-to-DC conversion device according to item 12 of the scope of patent application, further comprising: a first inductor coupled between the third switch and the output unit; a second inductor coupled between the fourth switch and the output unit; Between output units, and one end of the second inductor is coupled between the first inductor and the output unit.         The DC-to-DC conversion device according to item 13 of the scope of the patent application, further comprising: a second current sensing unit coupled to the multi-phase controller, two ends of the first inductor, and two of the second inductor, respectively. end.         The DC-to-DC conversion device according to item 12 of the application, wherein the multi-phase controller further includes an error amplifier and a plurality of comparators, the error amplifier is coupled to an output terminal of the DC-to-DC conversion device, and The error amplifier is coupled to the comparators, and the comparators are coupled to the time signal generating unit.