CN219936680U - Power supply unit and storage device driving system - Google Patents

Abstract

The utility model discloses a power supply unit and a storage device driving system. The power supply unit includes: the power supply module is used for converting the input voltage into output voltage and adjusting the output voltage according to a feedback signal of the output voltage so that the output voltage is a first voltage value in a first power supply mode and is a second voltage value in a second power supply mode; and an adjustment module providing a feedback signal according to the control signal, wherein the adjustment module comprises: the first resistor is connected between the output end and the second input end of the power supply module; the second resistor and the third resistor are sequentially connected in series between the second input end of the power supply module and the ground; the transistor is connected in parallel with the third resistor and is controlled by a control signal, and the control signal is at a first level in a first power supply mode so as to turn off the transistor; and in a second power supply mode at a second level to turn on the transistor. The power supply module can reduce the requirement on control signals and the deviation between the actual output voltage and the ideal output voltage.

Description

Power supply unit and storage device driving system

Technical Field

The present utility model relates to the field of memory cards, and in particular, to a power supply unit and a memory device driving system.

Background

The SD card is a new generation memory device based on a semiconductor flash memory, and is widely used on portable devices such as digital cameras, tablet computers, multimedia players, etc., due to its excellent characteristics of small size, high data transmission speed, hot-pluggable, etc.

With the development of technology, the data volume gradually becomes larger, so that the capacity and the transmission speed of the SD card are gradually improved. In the related art, SD cards can be classified into low-speed cards and high-speed cards. The low-speed card only supports the SD card to work in a low-speed mode, the I/O level of an interface is 3.3V, and the speed is limited when the SD card is read and written. The high-speed card can switch the working mode according to the I/O level of the SD card interface, and enter the high-speed mode when the I/O level is 1.8V; when the I/O level is 3.3V, the low speed mode is entered.

The prior art provides a power supply unit of an SD card, which can switch input voltage into 1.8V or 3.3V according to a control signal and output the input voltage to an I/O interface of the SD card, so that intelligent switching of the transmission rate of the SD card is realized, but the compatibility of the power supply unit is poor and the use scene is limited due to the higher requirement of the prior art on the control signal. Therefore, a new SD card power supply unit is needed to reduce the requirement for control signals, thereby adapting to more application scenarios.

Disclosure of Invention

In view of the above problems, an object of the present utility model is to provide a power supply unit and a storage device driving system, which reduce the requirements for control signals by changing the connection mode of transistors and resistors, so that the power supply unit is adapted to more application scenarios.

According to an aspect of the present utility model, there is provided a power supply unit including: the power supply module comprises a first input end and a second input end which are respectively used for receiving input voltage and feedback signals, and an output end which is used for providing output voltage; the power supply module is used for converting an input voltage into an output voltage and adjusting the output voltage according to a feedback signal of the output voltage so that the output voltage is adjusted to a first voltage value in a first power supply mode and is adjusted to a second voltage value in a second power supply mode; and an adjustment module providing the feedback signal to a second input of the power module according to a control signal, wherein the adjustment module comprises: the first resistor is connected between the output end and the second input end of the power supply module; the second resistor and the third resistor are sequentially connected in series between the second input end of the power supply module and the ground; and the transistor is connected in parallel with the third resistor, the control end of the transistor is controlled by the control signal, the control signal is of a first level in the first power supply mode to turn off the transistor, and the control signal is of a second level in the second power supply mode to turn on the transistor.

Optionally, the transistor is an NMOS transistor, where a drain of the NMOS transistor is connected to a middle node of the second resistor and the third resistor, a source of the NMOS transistor is grounded, and a gate of the NMOS transistor is used as a control end of the transistor to receive the control signal.

Optionally, the transistor is an NPN triode, a collector of the NPN triode is connected to a middle node of the second resistor and the third resistor, an emitter of the NPN triode is grounded, and a control end of the base of the NPN triode receives the control signal.

Optionally, the adjusting module further includes a first capacitor and a fourth resistor, the first capacitor is connected between the output end of the power module and ground, the fourth resistor is connected between the control end of the transistor and ground, and an intermediate node of the fourth resistor and the transistor receives the control signal.

Optionally, the adjusting module further includes a fifth resistor, and the control terminal of the transistor receives the control signal through the fifth resistor.

Optionally, the second level of the control signal satisfies that a product of a voltage value of the second level of the control signal and a resistance value of the fourth resistor is greater than a product of the transistor turn-on threshold and a sum of the fourth resistor and the fifth resistor.

Optionally, the power supply unit further includes a first filtering module and a second filtering module, the first filtering module includes a second capacitor and a third capacitor respectively connected between the first input end of the power supply module and ground, and the second filtering module includes a fourth capacitor and a fifth capacitor respectively connected between the output end and ground.

Optionally, the power module is a low dropout linear regulator or a DC-DC power converter.

According to a further aspect of the utility model, a storage device drive system is provided, characterized by comprising a power supply unit as described in any of the above, and a control unit, said control unit being connected to the storage device via a drive bus, said control unit being further connected to said power supply unit for providing said control signal to said power supply unit.

Optionally, the storage device is an SD card or a TF card.

Optionally, the output voltage of the power supply module is adjusted to a first voltage value in a first power supply mode and to a second voltage value in a second power supply mode to operate the memory device in a high speed mode or a low speed mode.

Optionally, the control unit is an SOC chip or an MCU chip.

According to the power supply unit of the embodiment, the high level of the control signal can be directly used as the on voltage of the transistor by changing the connection mode of the transistor, so that the requirement on the control signal is reduced, and the compatibility of the power supply unit is improved. Furthermore, as each voltage dividing resistor is connected in series, when the transistor is opened, the voltage dividing proportion of the resistor is more in accordance with the design, the influence of resistor selection on the actual output is reduced, and the control is more accurate.

Drawings

The above and other objects, features and advantages of the present utility model will become more apparent from the following description of embodiments of the present utility model with reference to the accompanying drawings, in which:

fig. 1 shows a schematic circuit diagram of a prior art power supply unit;

fig. 2 shows a schematic circuit diagram of a power supply unit of an embodiment of the utility model;

FIG. 3 illustrates a schematic block diagram of a storage device drive system of an embodiment of the present utility model;

FIG. 4 illustrates a flow chart of the operation of the storage device drive system shown in FIG. 3.

Detailed Description

The utility model will be described in more detail below with reference to the accompanying drawings. Like elements are denoted by like reference numerals throughout the various figures. For clarity, the various features of the drawings are not drawn to scale. Furthermore, some well-known portions may not be shown.

It should be appreciated that in the following description, a "circuit" may include a single or multiple combined hardware circuits, programmable circuits, state machine circuits, and/or elements capable of storing instructions for execution by the programmable circuits. When an element or circuit is referred to as being "connected to" another element or circuit is "connected between" two nodes, it can be directly coupled or connected to the other element or intervening elements may be present, the connection between the elements may be physical, logical, or a combination thereof. In contrast, when an element is referred to as being "directly coupled to" or "directly connected to" another element, it means that there are no intervening elements present between the two.

Also, certain terms are used throughout the description and claims to refer to particular components. It will be appreciated by those of ordinary skill in the art that a hardware manufacturer may refer to the same component by different names. The present patent specification and claims do not take the form of an element or components as a functional element or components as a rule.

Furthermore, it should be noted that relational terms such as first and second are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

Fig. 1 shows a schematic circuit diagram of a prior art power supply unit 10. The power supply unit 10 includes a power supply module 11 and a regulating module 12.

The power module 11 is configured to convert an input voltage Vin to an output voltage Vout, and includes a first input terminal for receiving the input voltage Vin; a second input terminal for receiving the feedback signal Vcs and an output terminal for outputting the output voltage Vout. The power module 11 is configured to convert an input voltage Vin into an output voltage Vout, and regulate the output voltage Vout according to a feedback signal Vcs of the output voltage Vout.

The adjustment module 12 is arranged to provide a feedback signal Vcs in dependence of the control signal Vg. As shown, the regulation module 12 includes resistors R1 to R4 and a transistor Q1. The resistors R1, R2 are serially connected in sequence between the output terminal of the power module 11 and ground, and the second input terminal of the power module 11 is connected to the intermediate node of the resistors R1 and R2 to receive the feedback signal Vcs. The resistor R3 and the transistor Q1 are sequentially connected in series to an intermediate node between the output end of the power module 11 and the resistors R1 and R2, wherein the transistor Q1 is an NMOS transistor, the drain is connected to the resistor R3, and the source is connected to the intermediate node between the resistors R1 and R2. The resistor R4 is connected in series between the gate of the transistor Q1 and ground and the intermediate node of the gate of the transistor Q1 and the resistor R4 receives the control signal Vg. Further, a gate protection diode is further disposed in the transistor Q1, and the gate protection diode is connected between the gate and the source, and prevents the transistor Q1 from being damaged by burning due to reverse connection.

The control signal Vg controls the on state of the transistor Q1. When the control signal Vg controls the transistor Q1 to be turned off, the resistance between the output terminal and the second input terminal of the power module 11 is the resistance of the resistor R1. Because the magnitude of the feedback signal Vcs is a preset value, the voltage is output according to the principle of series resistance voltage division

Vout＝(1+R1/R2)*Vcs (1)

When the control signal Vg controls the transistor Q1 to be turned on, the resistance between the second input terminal and the output terminal of the power module 11 is the resistance after the parallel connection of the resistors R1 and R3, i.e., (r1×r3)/(r1+r3), and the voltage is outputted according to the principle of series resistance voltage division

Vout＝{1+(R1*R3)/[(R1+R3)*R2]}*Vcs (2)

Therefore, when the feedback signal Vcs is a preset value, the output voltage Vout output to the I/O interface of the storage device is adjusted by setting the resistance values of the resistors R1, R2 and R3, so as to switch the operation mode of the storage device to a low-speed mode or a high-speed mode.

The above-described prior art power supply unit 10 has a disadvantage in that since the transistor Q1 is connected in series between the resistor R3 and the intermediate node of the resistors R1 and R2. According to the transistor turn-on principle, the gate-source voltage of the transistor Q1 needs to be greater than the turn-on threshold of the transistor Q1, i.e., the gate voltage of the transistor Q1 (i.e., the control signal Vg) needs to be greater than the sum of the turn-on threshold of the transistor Q1 and the preset value of the feedback signal Vcs. However, since the high level of the control signal Vg that some high-performance SOC chips can provide cannot meet the above conditions, the output voltage Vout cannot be switched, so that the use scenario of the above power supply unit 10 is limited.

Fig. 2 shows a schematic circuit diagram of the power supply unit 20 of the embodiment of the present utility model. As shown in the figure, the power supply unit 20 includes a power module 21, a regulating module 22, a first voltage stabilizing filter module 23, and a second voltage stabilizing filter module 24.

The power supply module 21 is used for converting an input voltage Vin into an output voltage Vout. Referring to fig. 2, the power module 21 includes a first input terminal for receiving an input voltage Vin; a second input for receiving a feedback signal Vcs; and an output terminal for outputting the output voltage Vout. The power module 21 is configured to convert an input voltage Vin into an output voltage Vout, and regulate the output voltage Vout according to a feedback signal Vcs of the output voltage Vout. Wherein, the input voltage Vin is usually 5V supply voltage; the power module 21 clamps the feedback signal Vcs to a preset value.

In some embodiments, the power module 21 is a power chip, and in some embodiments, is a DC-DC power converter; in this embodiment, taking a low dropout linear regulator (LDO) as an example, the LDO has very low self-noise and a high power supply rejection ratio, and can achieve high efficiency when the input voltage Vin is close to the output voltage Vout (e.g., when the input voltage Vin is 5V and the output voltage Vout is 3.3V). Further, the feedback signal Vcs may be clamped to, for example, 0.8V or other voltage values depending on the power module 21.

The adjustment module 22 is configured to provide a feedback signal Vcs in response to the control signal Vg. Referring to fig. 2, the regulation module 22 includes resistors R5 to R9, a transistor Q2, and a capacitor C5. As shown, the resistor R5 is connected between the output terminal and the second input terminal of the power module 21, and the resistors R6 and R7 are sequentially connected in series between the second input terminal of the power module 21 and ground. In this embodiment, since the resistors R5 to R7 are connected in series, the proportional relationship between the resistors is easier to calculate, which is convenient for circuit design and resistor selection, and reduces the deviation between the actual output voltage and the ideal output voltage caused by the deviation between the actual resistor selection and the theoretical calculation value.

The transistor Q2 is connected in parallel with the resistor R7, and in this embodiment, the transistor Q2 is an NMOS transistor, where the source of the NMOS transistor is grounded, and the drain is connected to the intermediate node between the resistors R6 and R7; the grid electrode of the NMOS tube receives a control signal Vg, and the conduction state of the NMOS tube is controlled by the control signal Vg. Based on the MOS tube conduction principle, when the gate-source voltage of the NMOS tube is larger than the conduction threshold value of the NMOS tube, the NMOS tube is conducted. In this embodiment, since the source electrode of the NMOS tube is grounded and the control signal Vg is used as the gate-source voltage, the requirement for the control signal Vg can be reduced, so that the power supply unit 20 of the present utility model is compatible with more usage scenarios. Meanwhile, compared with the prior art, when the NMOS tube is opened, the utility model has higher gate-source voltage, lower on-resistance, more accordant design of resistance voltage division ratio and more accurate output voltage Vout. In some embodiments, the transistor Q2 may be an NPN transistor, where an emitter of the NPN transistor is grounded, a collector of the NPN transistor is connected to an intermediate node of the resistors R6 and R7, and a base of the NPN transistor receives the control signal Vg and controls an on state of the NPN transistor by the control signal Vg. Based on the triode conduction principle, when the triode base voltage (i.e. the control signal Vg) is greater than the triode conduction threshold voltage, the triode is turned on.

When the control signal Vg is at low level, the transistor Q2 is turned off, and the resistors R5, R6, R7 are connected in series to the circuit, the feedback signal Vcs feeds back the voltage division of the resistor R5 to the output signal Vout, based on the principle of series resistor voltage division, the output voltage

Vout＝[1+R5/(R6+R7)]*Vcs (3)

When the control signal Vg is at a high level, the transistor Q2 is turned on, the resistors R5 and R6 are connected in series to the circuit, the resistor R7 is short-circuited, the feedback signal Vcs feeds back the voltage division of the resistor R5 to the output signal Vout, and the output voltage is based on the principle of series resistance voltage division

Vout＝(1+R5/R6)*Vcs (4)

In summary, when the feedback signal Vcs and the resistors R5 to R7 are preset values, different levels of the control signal Vg are output according to the target output voltage, and the voltage division condition of the resistor R5 is changed by changing the on state of the transistor Q2, so as to adjust the output voltage to the target output voltage.

In this embodiment, the storage device takes the SD card as an example, and when the voltage of the I/O interface of the SD card is 1.8V, the SD card enters a high-speed read-write mode; when the voltage of the I/O interface of the SD card is 3.3V, the SD card enters a low-speed reading and writing mode. It should be understood that the storage device of the present utility model should not be limited thereto and may also be a TF card, for example.

In the present embodiment, taking the feedback signal Vcs as an example of 0.8V, the resistances of the resistors R5, R6, and R7 are set to 140kΩ,44.2kΩ, and 68kΩ, respectively. I.e. when the control signal Vg is low level, the voltage is output

Vout＝[1+140K/(44.2K+68K)]*0.8＝1.798V (6)

The output voltage Vout is about 1.8V, and the SD card enters a high-speed reading and writing working mode;

when the control signal Vg is high, the voltage is outputted

Vout＝(1+140K/44.2K)*0.8＝3.334V (7)

I.e. the output voltage Vout is about 3.3V, the SD card enters a low-speed read-write mode of operation.

Therefore, the circuit design of the utility model is simpler and more direct, and the control of the output voltage Vout is more accurate. Meanwhile, according to the output voltage calculation formulas (3) and (4), the resistance values of the resistors R5, R6 and R7 are proportionally designed according to the preset value of the feedback signal Vcs. For example, in this embodiment, vcs is preset to 0.8V, and the resistances of the resistors R5, R6, and R7 satisfy R5: r6: r7=3.125: 1:1.5 can be satisfied to switch the output voltage Vout between 1.8V and 3.3V. Further, since the resistance value does not necessarily just match the ratio, the ratio can be generally floated by about 1% to 2%.

It should be understood that the output voltage Vout of the power supply unit 20 of the present utility model is not limited to 3.3V or 1.8V, but the output voltage Vout can be adjusted by adjusting the resistance values of the resistors R5, R6, R7 to adapt to more usage scenarios.

Further, in some embodiments, the adjustment module 22 also includes a capacitance C5. The capacitor C5 is connected between the output terminal of the power module 21 and ground, and is used for preventing voltage abrupt change and improving output voltage stability.

Further, in some embodiments, the adjustment module 22 also includes a resistor R8. The resistor R8 is connected between the gate of the transistor Q2 and the ground and is used as a current limiting resistor to prevent the transistor Q2 from being broken down and improve the circuit stability.

Further, in some embodiments, the adjusting module 22 further includes a resistor R9, and the gate of the transistor Q2 receives the control signal Vg through the resistor R9, so as to further reduce the risk of unstable turn-on of the transistor Q2. At this time, the high level Vgh of the control signal Vg and the on threshold Vth of the transistor Q2 need to satisfy vgh×r8> vth× (r8+r9) due to the voltage division effect of the resistors R8 and R9.

Further, in some embodiments, the power supply unit 20 further comprises a first filtering module 23. Referring to fig. 2, the first filtering module 23 includes capacitors C1 and C2 respectively connected between the first input terminal of the power module 21 and ground, and is used for keeping the voltage constant when the input voltage load ambient temperature, circuit parameters, etc. change, protecting the power supply unit 20, and prolonging the service life of the power supply unit 20.

Further, in some embodiments, the power supply unit 20 further includes a second filtering module 24. Referring to fig. 2, the second filtering module 24 includes capacitors C3 and C4 respectively connected between the output terminal of the power module 21 and ground, and is used for keeping the voltage constant, protecting the storage device, and prolonging the service life of the storage device when the voltage load ambient temperature, circuit parameters, etc. change.

Fig. 3 shows a schematic block diagram of a storage device driving system 1 of an embodiment of the present utility model.

Fig. 4 shows a flowchart of the operation of the storage device driving system 1 shown in fig. 3. The storage device drive system 1 is further described below in conjunction with fig. 4.

As shown, the storage device driving system 1 includes a power supply unit 20 and a control unit 30. The memory device is electrically connected to the control unit 30 via a drive bus. In the present embodiment, the storage device is an SD card, but it should be understood that the storage device of the present utility model is not limited thereto, and for example, the storage device may also be a TF card. Further, in some embodiments, the control unit 30 is an MCU chip; in some embodiments control unit 30 is a SOC chip. After the storage device driving system 1 is powered on, firstly, initializing the system, and after the initialization is completed, entering a standby mode.

The control unit 30 is connected to the power supply unit 20 and provides a control signal Vg to the power supply unit 20. The power supply unit 20 adjusts the voltage division condition of the resistor R5 according to the high-low level of the control signal Vg to convert the input voltage Vin into the output voltage Vout with different voltage values for supplying power to the memory device and the control unit 30. The storage device driving system 1 in the standby mode detects whether a storage device is inserted, and determines an operation mode supported by the storage device through communication between the low-speed mode and the storage device after detecting that the storage device is inserted, thereby outputting different control signals Vg according to the operation mode supported by the storage device. In this embodiment, taking the storage device as the SD card as an example, the power supply unit outputs Vout as 3.3V in the standby mode, and when detecting that the SD card is inserted, the control unit 30 communicates with the SD card in the low-speed mode (i.e., vout is 3.3V) to determine whether the SD card supports the high-speed mode. If the SD card is detected to support the high-speed mode, the output control signal Vg is low level, the output voltage Vout is 1.8V, and the SD card enters a high-speed read-write working mode; if the SD card is detected not to support the high-speed mode, the output control signal Vg is kept at a high level, the output voltage Vout is kept at 3.3V, and the SD card enters a low-speed read-write working mode.

According to the power supply unit and the storage device driving system of the embodiment, the high level of the control signal can be directly used as the on voltage of the transistor by changing the connection mode of the transistor, so that the requirement on the control signal is reduced, and the compatibility of the power supply unit is improved. Furthermore, as each voltage dividing resistor is connected in series, when the transistor is opened, the voltage dividing proportion of the resistor is more in accordance with the design, the influence of resistor selection on the actual output is reduced, and the control is more accurate.

Embodiments in accordance with the present utility model, as described above, are not intended to be exhaustive or to limit the utility model to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the utility model and the practical application, to thereby enable others skilled in the art to best utilize the utility model and various modifications as are suited to the particular use contemplated. The utility model is limited only by the claims and the full scope and equivalents thereof.

Claims (12)

1. A power supply unit, characterized by comprising:

the power module comprises a first input end and a second input end which are respectively used for receiving input voltage and feedback signals, and an output end which is used for providing output voltage; the power supply module is used for converting an input voltage into an output voltage and adjusting the output voltage according to a feedback signal of the output voltage so that the output voltage is adjusted to a first voltage value in a first power supply mode and is adjusted to a second voltage value in a second power supply mode; and

the adjusting module is used for providing the feedback signal to the second input end of the power supply module according to the control signal,

wherein, the adjustment module includes:

the first resistor is connected between the output end and the second input end of the power supply module;

the second resistor and the third resistor are sequentially connected in series between the second input end of the power supply module and the ground; and

and the control signal is in a first level in the first power supply mode to turn off the transistor, and is in a second level in the second power supply mode to turn on the transistor.

2. The power supply unit according to claim 1, wherein the transistor is an NMOS transistor, a drain of the NMOS transistor is connected to an intermediate node of the second resistor and the third resistor, a source of the NMOS transistor is grounded, and a gate of the NMOS transistor is used as a control terminal of the transistor to receive the control signal.

3. The power supply unit according to claim 1, wherein the transistor is an NPN transistor, a collector of the NPN transistor is connected to an intermediate node between the second resistor and the third resistor, an emitter of the NPN transistor is grounded, and a control terminal of the base of the NPN transistor receives the control signal.

4. The power supply unit of claim 1, wherein the conditioning module further comprises a first capacitor and a fourth resistor,

the first capacitor is connected between the output end of the power supply module and the ground,

the fourth resistor is connected between the control end of the transistor and the ground, and an intermediate node of the fourth resistor and the transistor receives the control signal.

5. The power supply unit of claim 4, wherein the regulation module further comprises a fifth resistor through which the control terminal of the transistor receives the control signal.

6. The power supply unit of claim 5, wherein the second level of the control signal satisfies that a product of a voltage value of the second level of the control signal and a resistance value of the fourth resistor is greater than a product of the transistor turn-on threshold and a sum of the fourth resistor and the fifth resistor.

7. The power supply unit of claim 1, further comprising a first filter module and a second filter module,

the first filtering module comprises a second capacitor and a third capacitor which are respectively connected between the first input end of the power supply module and the ground;

the second filtering module comprises a fourth capacitor and a fifth capacitor which are respectively connected between the output end and the ground.

8. The power supply unit of claim 1, wherein the power supply module is a low dropout linear regulator or a DC-DC power converter.

9. A storage device drive system, comprising:

the power supply unit according to any one of claims 1 to 8, and

the control unit is connected with the storage device through a drive bus, is also connected with the power supply unit and provides the control signal for the power supply unit.

10. The storage device driving system according to claim 9, wherein the storage device is an SD card or a TF card.

11. The storage device driving system of claim 10, wherein the output voltage of the power supply module is regulated to a first voltage value in a first power supply mode and to a second voltage value in a second power supply mode to operate the storage device in a high speed mode or a low speed mode.

12. The storage device driving system according to claim 11, wherein the control unit is an SOC chip or an MCU chip.