This application claims priority to Chinese Patent Application No. 201410678748.7 filed on Nov. 24, 2014, the contents of which are incorporated by reference herein in its entirety.
The subject matter herein generally relates to a voltage adjusting apparatus.
Printed circuit boards (PCBs) usually have slots for inserting memory chips. Power supplies provided to the memory chips include 1.5 volts, 1.35 volts, and 1.25 volts direct current (“DC”) voltages. A conventional PCB only provides a single DC voltage, which cannot meet the requirements when multiple memory chips are installed on the same PCB.
Implementations of the present technology will now be described, by way of example only, with reference to the attached figures.
It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein can be practiced without these specific details. In other instances, methods, procedures and components have not been described in detail so as not to obscure the related relevant feature being described. Also, the description is not to be considered as limiting the scope of the embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features of the present disclosure.
Several definitions that apply throughout this disclosure will now be presented.
The term “coupled” is defined as connected, whether directly or indirectly through intervening components, and is not necessarily limited to physical connections. The connection can be such that the objects are permanently connected or releasably connected. The term “comprising,” when utilized, means “including, but not necessarily limited to”; it specifically indicates open-ended inclusion or membership in the so-described combination, group, series and the like. “Unit” means a collection of electronic hardware alone or in combination with software configured for a particular task or function, although units may overlap or share components.
The first GPIO port GPIO1 is electrically coupled to the first terminal of the first switch Q1. The first terminal of the first switch Q1 is configured to receive a second direct current (DC) voltage via the fifth resistor R5. The second terminal of the first switch Q1 is grounded. The third terminal of the first switch Q1 is configured to receive the second DC voltage via the sixth resistor R6. The third terminal of the first switch Q1 is electrically coupled to the first terminal of the second switch Q2 via the seventh resistor R7. The second terminal of the second switch Q2 is grounded. The third terminal of the second switch Q2 is electrically coupled to the voltage dividing module 300.
The second GPIO port GPIO2 is configured to receive the second DC voltage via the eighth resistor R8. A connecting point between the second GPIO port GPIO2 and the eighth resistor R8 is electrically coupled to the first terminal of the third switch Q3 via the ninth resistor R9. The second terminal of the third switch Q3 is grounded. The third terminal of the third switch Q3 is electrically coupled to the voltage dividing module 300. In at least one embodiment, the second DC voltage is substantially +3.3 volts.
The voltage dividing module 300 includes a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4. The voltage converting unit 400 includes a DC voltage input terminal VDD, a DC voltage output terminal VOUT, and a feedback terminal FB. The DC voltage input terminal VDD is configured to receive a first DC voltage. The DC voltage output terminal VOUT is electrically coupled to the feedback terminal FB via the first resistor R1. A connecting point between the feedback terminal FB and the first resistor R1 is electrically coupled to the third terminal of the second switch Q2 via the second resistor R2. A connecting point between the third terminal of the second switch Q2 and the second resistor R2 is electrically coupled to the third terminal of the third switch Q3 via the third resistor R3. A connecting point between the third terminal of the third switch Q3 and the third resistor R3 is grounded via the fourth resistor R4.
In at least one embodiment, a resistance of each of the first resistor R1 and the second resistor R2 is substantially 10 kilo-ohms. A resistance of each of the third resistor R3 and the fourth resistor R4 is substantially 2.49 kilo-ohms. The first DC voltage is substantially +5 volts.
In use, the first GPIO port GPIO1 and the second GPIO port GPIO2 of the input output control unit 100 output different voltage level control signals according to power requirements of an electronic device (not shown). The voltage converting unit 400 converts the +5 volts first DC voltage to a feedback voltage which is output by the feedback terminal FB. The DC voltage output terminal VOUT of the voltage converting unit 400 outputs the corresponding working voltage to the electronic device according to the resistor connected in the voltage dividing module 300. In at least one embodiment, the electronic device is a memory chip. The feedback voltage is +0.75 volts.
When the first GPIO port GPIO1 outputs a low voltage level control signal to the first terminal of the first switch Q1, the first switch Q1 turns off. The first terminal of the second switch Q2 receives the +3.3 volts second DC voltage. The second switch Q2 turns on. The first resistor R1 and the second resistor R2 are connected in the voltage dividing module 300 by the switching module 200. The working voltage Vout is calculated by the following formula:
Vout=Vfb×(r1+r2)/r2.
When the first GPIO port GPIO1 and the second GPIO port GPIO2 both output high voltage level control signals to the first terminals of the first switch Q1 and the third switch Q3 respectively, the first switch Q1 and the third switch Q3 both turn on. The first terminal of the second switch Q2 is grounded via the first switch Q1. The second switch Q2 turns off The first resistor R1, the second resistor R2, and the third resistor R3 are connected in the voltage dividing module 300 by the switching module 200. The working voltage Vout is calculated by the following formula:
Vout=Vfb×(r1+r2+r3)/(r2+r3).
When the first GPIO port GPIO1 outputs a high voltage level control signal to the first terminal of the first switch Q1 and the second GPIO port GPIO2 outputs a low voltage level control signal to the first terminal of the third switch Q3 respectively, the first switch Q1 turns on, the third switch Q3 turns off. The first terminal of the second switch Q2 is grounded via the first switch Q1. The second switch Q2 turns off The first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4 are connected in the voltage dividing module 300 by the switching module 200. The working voltage Vout is calculated by the following formula:
Vout=Vfb×(r1+r2+r3+r4)/(r2+r3+r4).
In the above formula, r1, r2, r3, and r4 represent resistances of the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4 respectively. According to the above formula, the working voltage Vout is 1.5 volts if the first GPIO port GPIO1 outputs the low voltage level control signal, the working voltage Vout is 1.35 volts if the first GPIO port GPIO1 and the second GPIO port GPIO2 both output high voltage level control signals, and the working voltage Vout is 1.25 volts if the first GPIO port GPIO1 and the second GPIO port GPIO2 output the high voltage level control signal and the low voltage level control signal respectively.
In an original state, when the input output control unit 100 does not work, the first GPIO port GPIO1 and the second GPIO port GPIO2 cannot output the control signals. The first terminals of the first switch Q1 and the third switch Q3 receive the +3.3 volts second DC voltage. The first switch Q1 and the third switch Q3 both turn on. The working voltage Vout is 1.35 volts.
The embodiments shown and described above are only examples. Many details are often found in the art such as the other features of a voltage adjusting apparatus. Therefore, many such details are neither shown nor described. Even though numerous characteristics and advantages of the present technology have been set forth in the foregoing description, together with details of the structure and function of the present disclosure, the disclosure is illustrative only, and changes may be made in the detail, including in matters of shape, size and arrangement of the parts within the principles of the present disclosure up to, and including the full extent established by the broad general meaning of the terms used in the claims. It will therefore be appreciated that the embodiments described above may be modified within the scope of the claims.
Number | Date | Country | Kind |
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201410678748.7 | Nov 2014 | CN | national |