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Y F 20 Voltage Amplifying Unti K 3 O Switching Unit US 20070088962Al (19) United States (12) Patent Application Publication (10) Pub. No.: US 2007/0088962 A1 Yu (43) Pub. Date: Apr. 19, 2007 (54) FREQUENCY ADJUSTING CIRCUIT FOR (30) Foreign Application Priority Data CPU Oct. 14, 2005 (CN) ............................ .. 2005101003597 (75) Inventor: Chia-Chuan Yu, Tu-Cheng (TW) Publication Classi?cation Correspondence Address: PCE INDUSTRY, INC. (51) Int. Cl. ATT. CHENG-JU CHIANG JEFFREY T. G06F 1/00 (2006.01) KNAPP (52) U.S. c1. ............................................................ ..713/300 458 E. LAMBERT ROAD (57) ABSTRACT FULLERTON, CA 92835 (US) A frequency adjusting circuit for a central processing unit (73) Assignee: HON HAI PRECISION INDUSTRY (CPU) includes a transforming unit for transforming a CO., LTD., Tu-Cheng (TW) change of a current signal of the CPU into a Voltage signal, an amplifying unit for amplifying the Voltage signal from the transforming unit, a switching unit being turned on or turned (21) Appl, NQ; 11/309,277 oif by the ampli?ed Voltage signal from the amplifying unit, and a basic input/output chip for regulating a frequency of (22) Filed: Jul. 21, 2006 the CPU through a clock generator. 60 50 CPU 4 l 0 Power . supply —> Transformlng unit y f 20 Voltage amplifying unti K 3 O Switching unit 40 K Adjusting unit Patent Application Publication Apr. 19, 2007 Sheet 1 0f 2 US 2007/0088962 A1 5O CPU '4 \ l / 1° Power . supply —> Transfonnlng unit 4 K 20 Voltage amplifying unti l r 30 Switching unit l r 40 Adjusting unit FIG. 1 Patent Application Publication Apr. 19, 2007 Sheet 2 0f 2 US 2007/0088962 A1 _ _ _ _ _M86 _5:22am N.65 US 2007/0088962 A1 Apr. 19, 2007 FREQUENCY ADJUSTING CIRCUIT FOR CPU 60, in accordance With a preferred embodiment of the present invention is shoWn. The frequency adjusting circuit DESCRIPTION includes a transforming unit 10, a voltage amplifying unit 20, a sWitching unit 30, an adjusting unit 40 that is for [0001] 1. Field of the Invention regulating a frequency of the CPU 60, and a poWer supply [0002] The present invention relates to a frequency adjust 50 providing a Working voltage for the transforming unit 10. ing circuit for a central processing unit (CPU), and particu The transforming unit 10 receives a current signal from the larly to a frequency adjusting circuit Which dynamically CPU 60 and transforms the current signal into a voltage adjusts a frequency of a CPU according to a variation of a signal. The voltage signal is then sent to the voltage ampli load on the CPU. fying unit 20 and ampli?ed. The ampli?ed signal is input to the sWitching unit 30, and then the sWitching unit 30 outputs [0003] 2. Description of Related Art a control signal to the adjusting unit 40 according to the [0004] Computers are being used today to perform a Wide ampli?ed voltage signal. The adjusting unit 40 regulates a variety of tasks. Many different areas of business, industry, frequency of the CPU 60 according to the control signal. government, education, and entertainment need to use the computers. Computers have also become a key technology [0012] Referring to FIG. 2, a circuit diagram of FIG. 1 is for communicating ideas, data, and trends betWeen and shoWn. The transforming unit 10 includes a primary induc among business professionals. tion coil L1 and a secondary induction coil L2. The ampli fying unit 20 includes an ampli?er U, and resistors R1, R2. [0005] Execution speed of a computer device depends on The sWitching unit 30 includes a metal-oxide semiconductor the performance characteristics of the individual compo ?eld-effect transistor (MOSFET) Q. The adjusting unit 40 nents such as a central processing unit (CPU). The speed at includes a basic input/output chip and a clock generator Which the CPU executes softWare instructions, is often most connected to the basic input/output chip. The MOSFET Q is critical to overall execution speed of the computer device. an n-channel depletion MOSFET. A 12V voltage is input to Generally, a method to increase a frequency (also called a positive terminal of the primary induction coil L1, and a overclocking) of the CPU is to set the frequency of the CPU negative terminal of the primary induction coil L1 is con in a basic input/output system (BIOS). Hence, the CPU nected to an input terminal T1 of the CPU. The CPU 60 Works With the predetermined frequency until users reset the outputs a current signal to the primary induction coil L1 frequency of the CPU in the BIOS. HoWever, a load applied through the input terminal T1. A negative terminal of the on the CPU is variable, While the CPU Work frequency is secondary induction coil L2 is grounded. A positive terminal not. Furthermore, sensitivity of a load detector for the CPU of the secondary induction coil L2 is connected to an is also important if the load detector is used to determine the inverting input of the ampli?er U through the resistor R1. A load of the CPU. Poor sensitivity of the load detector cannot non-inverting input of the ampli?er U is grounded. The help to improve Work ef?ciency of the CPU. resistor R2 is connected betWeen the inverting input and an [0006] What is needed is a frequency adjusting circuit output of the ampli?er U. The output of the ampli?er U is Which dynamically adjusts a frequency of a CPU to vary connected to a gate of the MOSFET Q. A source of the With the load. MOSFET Q is grounded. A drain of the MOSFET Q is connected to the basic input/output chip. The clock genera SUMMARY OF THE INVENTION tor is connected to the CPU 60 through an output terminal T2. [0007] An exemplary frequency adjusting circuit for a central processing unit (CPU) includes a transforming unit [0013] In the transforming unit 10, the current signal of the for transforming a change of a current signal of the CPU into CPU 60 is applied to the primary induction coil L1. When a voltage signal, an amplifying unit for amplifying the a load applied on the CPU 60 changes, the current signal voltage signal from the transforming unit, a sWitching unit applied on the primary induction coil L1 also changes. being turned on or turned off by the ampli?ed voltage signal Therefore, the secondary induction coil L2 produces an from the amplifying unit, and a basic input/output chip for induction current signal according to the electromagnetic regulating a frequency of the CPU through a clock generator. induction laW. An electromotive force of the secondary induction coil L2 is as folloWs: E2=MAi1/At, Where “Ail/ [0008] Other objects, advantages and novel features Will At” speci?es a rate of change in the current signal of the become more apparent from the folloWing detailed descrip primary induction coil L1, and “M” is a mutual inductance tion When taken in conjunction With the accompanying betWeen the primary induction coil L1 and the secondary draWings, in Which: induction coil L2. BRIEF DESCRIPTION OF THE DRAWINGS [0014] An output voltage of the ampli?er U is set by the resistors R1 and R2 as folloWs: Vout=E2(R2/R1). A resis [0009] FIG. 1 is a block diagram of a frequency adjusting tance of the resistor R2 is greater than that of the resistor R1, circuit for a CPU, in accordance With a preferred embodi thus, the ampli?er U ampli?es the electromotive force E2 of ment of the present invention; and the secondary induction coil L2. [0010] FIG. 2 is a circuit diagram of FIG.1. [0015] If the load applied to the CPU 60 increases, the DETAILED DESCRIPTION OF THE current signal applied to the primary induction coil L1 INVENTION increases, that is to say, Ai1/At>0. Because a polarity of the output voltage of the ampli?er U is contrary to that of the [0011] Referring to FIG. 1, a block diagram of a frequency voltage applied on the inverting input of the ampli?er U, the adjusting circuit for an electronic processing unit like a CPU MOSFET Q is turned on, and the control signal is input to US 2007/0088962 Al Apr. 19, 2007 the basic input/output chip. The basic input/output chip output chip receives the control signal, and the basic input/ increases the frequency of the CPU 60 according to an output chip regulates the CPU to Work With a relatively increasing magnitude of the current signal of the CPU 60. If higher frequency through the clock generator, and When the the load applied to the CPU 60 decreases, Ai1/At<0, the MOSFET is turned off, the basic input/output chip regulates polarity of electromotive force of the secondary induction the CPU to Work With an original loWer frequency through coil L2 is then contrary to that of the current signal of the the clock generator. CPU 60, and the MOSFET Q is turned off, and the basic 7. A frequency adjusting circuit for a central processing input/output chip regulates the CPU 60 to Work With an unit (CPU), comprising: original loWer frequency. So, the adjusting circuit of the preferred embodiment dynamically regulates the frequency a transforming unit for transforming a change of a current of the CPU 60 according to the load applied to the CPU 60. signal of the CPU into a voltage signal; Due to use of the induction coils L1 and L2, sensitivity of the transforming unit 10 to detect the load of the CPU 60 is an amplifying unit for amplifying the voltage signal from high.
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