U.S. patent application number 12/274360 was filed with the patent office on 2010-04-08 for voltage converting circuit.
This patent application is currently assigned to HON HAI PRECISION INDUSTRY CO., LTD.. Invention is credited to CHUAN-TSAI HOU.
Application Number | 20100084543 12/274360 |
Document ID | / |
Family ID | 42026966 |
Filed Date | 2010-04-08 |
United States Patent
Application |
20100084543 |
Kind Code |
A1 |
HOU; CHUAN-TSAI |
April 8, 2010 |
VOLTAGE CONVERTING CIRCUIT
Abstract
A voltage converting circuit for converting a first voltage
signal into a second voltage signal for supplying voltage for an
electronic component includes a photoelectric coupler and a
connector. The photoelectric coupler includes a light-emitting
element and a photosensor. The light-emitting element includes a
first terminal configured for receiving the first voltage signal.
The photosensor includes a first terminal connected to a power
supply, and a second terminal configured for outputting the second
voltage signal. The connector configured for connecting the
photosensor and the electronic component. When the first voltage
signal is at a high level, the light-emitting element emits light
to turn on the photosensor, the power supply makes the voltage
level of the second voltage signal sent out by the photosensor to
satisfy a voltage demand of the electronic component.
Inventors: |
HOU; CHUAN-TSAI; (Tu-Cheng,
TW) |
Correspondence
Address: |
PCE INDUSTRY, INC.;ATT. Steven Reiss
288 SOUTH MAYO AVENUE
CITY OF INDUSTRY
CA
91789
US
|
Assignee: |
HON HAI PRECISION INDUSTRY CO.,
LTD.
Tu-Cheng
TW
|
Family ID: |
42026966 |
Appl. No.: |
12/274360 |
Filed: |
November 20, 2008 |
Current U.S.
Class: |
250/214SW |
Current CPC
Class: |
H05K 7/20209 20130101;
G06F 1/26 20130101 |
Class at
Publication: |
250/214SW |
International
Class: |
H03K 17/78 20060101
H03K017/78 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 8, 2008 |
CN |
200810304780.3 |
Claims
1. A voltage converting circuit comprising: a control chip for
outputting a first voltage signal; a first photoelectric coupler to
convert the first voltage signal into a second voltage signal,
wherein the first photoelectric coupler comprises: a first
light-emitting element comprising a first terminal connected to the
control chip to receive the first voltage signal, and a grounded
second terminal; and a first photosensor comprising a first
terminal connected to a first power supply, and a second terminal
outputting the second voltage signal to supply voltage to an
electronic component; a second photoelectric coupler to convert a
third voltage signal sent out by the electronic component into a
fourth voltage signal for supplying voltage for a detecting chip,
wherein the second photoelectric coupler comprises: a second
light-emitting element comprising a first terminal receiving the
third voltage signal from the electronic component, and a grounded
second terminal; and a second photosensor comprising a first
terminal connected to a second power supply, and a second terminal
connected to the detecting chip to output the fourth voltage signal
to the detecting chip; and a connector connected to the electronic
component, wherein the connector comprises a power pin connected to
the second terminal of the first photosensor to receive the second
voltage signal, a sensing yin connected to the first terminal of
the second light-emitting element to output the third voltage
signal, and a grounded pin; wherein the first photosensor is
arranged such that a light emitted from the first light-emitting
element turns on the first photosensor in response to the first
voltage signal being at a high level, and wherein the first power
supply adjusts the voltage level of the second voltage signal sent
out by the first photosensor to satisfy a voltage demand of the
electronic components and wherein the second photosensor is
arranged such that a light emitted from the second light-emitting
element turns on the second photosensor in response to the third
voltage signal being at a high level, and wherein the second power
supply adjusts the voltage level of the fourth voltage signal sent
out by the second photosensor to satisfy a voltage demand of the
detecting chip.
2. The voltage converting circuit of claim 1, wherein the first and
second light-emitting elements are light-emitting diodes, the first
terminals of the first and second light-emitting elements are
anodes, and the second terminals of the first and second
light-emitting elements are cathodes.
3. The voltage converting circuit of claim 1, wherein the first and
second photosensors are photoelectric triodes, the first terminals
of the first and second photosensors are collectors, and the second
terminals of the first and second photosensors are emitters.
4. (canceled)
5. The voltage converting circuit of claim 1, wherein a resistor is
connected between the connector and the second light-emitting
element.
6. The voltage converting circuit of claim 1, wherein the fourth
voltage signal is a pulse signal, the detecting chip detects
whether the electronic component works normally according to the
fourth voltage signal.
7-8. (canceled)
9. A circuit for a fan, comprising: a control chip for outputting a
first voltage signal; a detecting chip configured for detecting a
rotation speed of the fan; a first photoelectric coupler comprising
a first input connected to the control chip to receive the first
voltage signal, a second input connected to a first power supply,
and an output, wherein the first voltage signal is capable of
controlling the first photoelectric coupler to turn on such that
the output outputs a second voltage signal substantially equal to
that of the first power supply to the fan; a second photoelectric
coupler comprising a first input receiving a third voltage signal
from the fan which indicates actual rotation speed of the fan, a
second input connected to a second power supply, and an output,
wherein the second voltage signal is capable of controlling the
second photoelectric coupler to turn on such that the output of the
second photoelectric coupler outputs a fourth voltage signal
substantially equal to that of the second power supply to the
detecting chip; and a connector connected to the fan, wherein the
connector comprises a power pin to receive the second voltage
signal from the output of the first photoelectric coupler, a
sensing pin to transmit the third voltage signal to the first input
of the second photoelectric coupler, and a grounded pin.
10. The circuit of claim 9, wherein the first photoelectric coupler
comprises: a first light-emitting element comprising a first
terminal connected to the control chip and a grounded second
terminal; and a first photosensor comprising a first terminal
connected to the first power supply and a second terminal connected
to the connector.
11-13. (canceled)
14. The circuit of claim 10, wherein the second photoelectric
coupler comprises: a second light-emitting element comprising a
first terminal connected to the connector and a grounded second
terminal; and a second photosensor comprising a first terminal
connected to the second power supply, and a second terminal
connected to the detecting chip.
15. The circuit of claim 14, wherein the first and second
light-emitting elements are light-emitting diodes, the first
terminals of the first and second light-emitting elements are
anodes, and the second terminals of the first and second
light-emitting elements are cathodes.
16. The circuit of claim 14, wherein the first and second
photosensors are photoelectric triodes, the first terminals of the
first and second photosensors are collectors, and the second
terminals of the first and second photosensors are emitters.
Description
BACKGROUND
[0001] 1. Technical Field
[0002] The present disclosure relates to converting circuits, and
particularly to a voltage converting circuit.
[0003] 2. Description of the Related Art
[0004] Generally, a voltage converting circuit is connected between
a control chip and an electronic component, such as a fan. The
voltage converting circuit is configured for converting a low
voltage signal, such as a 3V signal that is unfit for the fan, sent
out by the control chip to a high voltage signal, such as a 12V
signal that is fit for the fan, to meet the voltage demand of the
fan. However, the voltage converting circuit generally includes a
converting chip and a plurality of transistors, which creates
complications and added cost. Furthermore, the voltage converting
circuit may distort signals during transmission, which may degrade
the fan control circuit's ability to control the fan.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a block diagram of an embodiment of a voltage
converting circuit, together with a fan, a control chip, and a
detecting chip.
[0006] FIG. 2 is a circuit diagram of FIG. 1.
DETAILED DESCRIPTION
[0007] Referring to FIGS. 1 and 2, an embodiment of a voltage
converting circuit 6 electronically coupled on a motherboard for
converting a voltage supplied for a fan 40, includes a first
photoelectric coupler 10, a second photoelectric coupler 20, and a
connector 30 configured for connecting to the fan 40. The first
photoelectric coupler 10 includes a first light-emitting element,
such as a light-emitting diode (LED) D1, and a first photosensor,
such as a photoelectric triode Q1. The second photoelectric coupler
20 includes a second light-emitting element, such as an LED D2, and
a second photosensor, such as a photoelectric triode Q2. The
connector 30, such as a 3-pin fan connector, includes a power pin
VCC, a grounded pin GND, and a sensing pin Sense.
[0008] The anode of the LED D1 receives a pulse width modulation
(PWM) control signal from a control chip 50 of the motherboard via
a resistor R1, and the cathode of the LED D1 is connected to the
grounded pin GND of the connector 30. The collector of the
photoelectric triode Q1 is connected to a first power supply VCC1,
such as a 12V power supply. The emitter of the photoelectric triode
Q1 is connected to the power pin VCC of the connector 30 to output
a PWM signal to the connector 30. The anode of the LED D2 is
connected to the sensing pin Sense of the connector 30 via a
resistor R2, to receive a sample signal, which is a pulse signal,
from the connector 30. The cathode of the LED D2 is grounded. The
collector of the photoelectric triode Q2 is connected to a second
power supply VCC2, such as a 3V power supply. The emitter of the
photoelectric triode Q2 outputs a sensing signal, which is a pulse
signal to a detecting chip 60. The duty cycle of the PWM control
signal sent out by the control chip 50 can be adjusted, to control
the rotation speed of the fan 40.
[0009] The duty cycle of the PWM control signal is similar to the
duty cycle of the PWM signal, while the voltage level of the PWM
control signal is different from the voltage level of the PWM
signal. The voltage level of the PWM control signal is an operating
voltage of the control chip 50, equal to the voltage of the second
power supply VCC2. The voltage level of the PWM signal is equal to
the voltage of the first power supply VCC1. The duty cycle of the
sample signal is similar to the duty cycle of the sensing signal,
while the voltage level of the sample signal is different from the
voltage level of the sensing signal. The voltage level of the
sample signal is an operating voltage of the fan 40, equal to the
voltage of the first power supply VCC1. The voltage level of the
sensing signal is equal to the voltage of the second power supply
VCC2. In summary, both the voltage levels of the PWM control signal
and the sensing signal are equal to the voltage of the first power
supply VCC1, and both the voltage levels of the PWM signal and the
sample signal are equal to the voltage of the second power supply
VCC2.
[0010] When the PWM control signal sent out by the control chip 50
is at a high level, such as 3V, the LED D1 turns on. Accordingly,
because the LED D1 is turned on, the LED D1 emits light so as to
turn on the photoelectric triode Q1. The first power supply VCC1
pulls the voltage level of the PWM signal up to that of the first
power supply VCC1 to satisfy the voltage demand of the fan 40. The
fan 40 rotates at a speed controlled by the PWM signal. At this
time, the sensing pin Sense of the connector 30 sends out the
sample signal to the LED D2. When the sample signal is at a high
level, such as 12V, the LED D2 turns on to emit light to turn on
the photoelectric triode Q2. The second power supply VCC2 pulls the
voltage level of the sensing signal down to that of the second
power supply VCC2 to satisfy the voltage demand of the detecting
chip 60. The detecting chip 60 detects the actual rotation speed of
the fan 40 according to the sensing signal to determine whether the
fan 40 works normally. In one embodiment, the detecting chip 60 is
an ITE8712 detecting chip. It may be appreciated that the LED D1
and the LED D2 may emit light in the visible light spectrum.
[0011] The LED D1 is not physically or electrically connected to
the photoelectric triode Q1, and the LED D2 is not physically or
electrically connected to the photoelectric triode Q2. Therefore,
each of the first photoelectric coupler 10 and the second
photoelectric coupler 20 has an electrical isolation function,
which can avoid the PWM control signal and the sample signal being
distorted during the process of converting voltage.
[0012] It is to be understood, however, that even though numerous
characteristics and advantages of the present disclosure have been
set forth in the foregoing description, together with details of
the structure and function of the disclosure, the disclosure is
illustrative only, and changes may be made in detail, especially in
matters of shape, size, and arrangement of parts within the
principles of the disclosure to the full extent indicated by the
broad general meaning of the terms in which the appended claims are
expressed.
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