TWI395087B

TWI395087B - Pvt-independent current-controlled oscillator

Info

Publication number: TWI395087B
Application number: TW98137076A
Authority: TW
Inventors: Meng Chih Weng
Original assignee: Himax Tech Ltd
Priority date: 2009-11-02
Filing date: 2009-11-02
Publication date: 2013-05-01
Also published as: TW201116967A

Description

與製程-電壓-溫度(PVT)無關的電流控制振盪器Current controlled oscillator independent of process-voltage-temperature (PVT)

本發明係有關於電流控制振盪器(current-controlled oscillator，CCO)，特別係有關於不會受到製程變動(process variation)、供應電壓變動(supply voltage variation)和溫度漂移(temperature deviation)影響的電流控制振盪器。The present invention relates to a current-controlled oscillator (CCO), and more particularly to a current that is not affected by process variation, supply voltage variation, and temperature deviation. Control the oscillator.

電流振盪器係為一種電子振盪器，其藉由控制電流而產生振盪頻率。然而，與多數電子元件類似，電流振盪器的效能通常受到多種因素的影響，例如製程變動、供應電壓變動和溫度漂移(合稱為製程-電壓-溫度，文後簡寫為PVT)。第1圖為顯示電流控制振盪器的圖示。在第1圖中，電流控制振盪器10用以產生振盪頻率F_out ，其中振盪頻率F_out 由電流源I_c 所控制。然而，雖然電流控制振盪器10具有固定的電流源I_c ，但其輸出的振盪頻率F_out 還是會受到製程電壓溫度的影響而變動。The current oscillator is an electronic oscillator that generates an oscillation frequency by controlling the current. However, like most electronic components, the performance of a current oscillator is often affected by a number of factors, such as process variation, supply voltage variation, and temperature drift (collectively, process-voltage-temperature, abbreviated as PVT). Figure 1 is a diagram showing a current controlled oscillator. In FIG 1, the current controlled oscillator 10 to generate an oscillating frequency F _out, F _out where the oscillation frequency is controlled by the current source I _c. However, although the current control oscillator 10 having a fixed current source I _c, but the output of the oscillation frequency F _out the process can be affected voltage of the temperature fluctuates.

第2圖描繪電流控制振盪器的特徵曲線。在第2圖很清楚地顯示，電流控制振盪器10輸出的振盪頻率F_out 與溫度成反比，對於理想的電流控制振盪器而言，上述現象並不樂見。Figure 2 depicts the characteristic curve of the current controlled oscillator. It is clearly shown in Fig. 2 that the oscillation frequency _Fout output from the current controlled oscillator 10 is inversely proportional to the temperature, which is not desirable for an ideal current controlled oscillator.

本發明之一實施例提供一種與製程-電壓-溫度(PVT)無關的電流控制振盪器，包括：製程和電壓控制器、電流控制振盪器以及溫度控制器。電流控制振盪器耦接至製程和電壓控制器，用以輸出振盪頻率。溫度控制器耦接至製程和電壓控制器和電流控制振盪器，用以提供總電流予製程和電壓控制器和電流控制振盪器一同共享，其中若電流控制振盪器因製程變動而使振盪頻率高於既定頻率時，則製程和電壓控制器藉由增加製程和電壓控制器的電流，減少電流控制振盪器的電流，並且若電流控制振盪器因製程變動而使振盪頻率低於既定頻率時，則製程和電壓控制器藉由減少控制器的電流，增加電流控制振盪器的電流，藉此動態地調整上述振盪頻率。One embodiment of the present invention provides a process-voltage-temperature (PVT) independent current controlled oscillator comprising: a process and voltage controller, a current controlled oscillator, and a temperature controller. The current controlled oscillator is coupled to the process and voltage controller for outputting the oscillation frequency. The temperature controller is coupled to the process and voltage controller and the current controlled oscillator to provide total current to the process and the voltage controller and the current controlled oscillator are shared together, wherein if the current controlled oscillator has a high oscillation frequency due to process variation At a given frequency, the process and voltage controller reduces the current of the current-controlled oscillator by increasing the current of the process and voltage controller, and if the current-controlled oscillator causes the oscillation frequency to be lower than the predetermined frequency due to process variations, then The process and voltage controller dynamically adjusts the above-mentioned oscillation frequency by reducing the current of the controller and increasing the current of the current-controlled oscillator.

下述實施例用以實現本發明最佳模式。實施例用以說明本發明之一般性概念，並非用以限定本發明，本發明的範圍當視所附之申請專利範圍而定。The following examples are presented to best practice the invention. The examples are intended to be illustrative of the general inventive concept and are not intended to limit the scope of the invention.

第3圖為本發明之一實施例，其描繪與製程電壓溫度無關的一種電流控制振盪器30。與製程電壓溫度無關的電流控制振盪器30包括溫度控制器31(文後簡寫為T-控制器31)、製程和電壓控制器32(文後簡寫為PV-控制器32)以及電流控制振盪器10。T-控制器31除了提供電壓V_N1 至PV-控制器32，也提供電流I_M6 給PV-控制器32和電流控制振盪器10一同共享。此外，T-控制器31用以避免電流控制振盪器10受到溫度漂移的影響，且PV-控制器32用以避免電流控制振盪器10受到製程和供應電壓變動的影響，因此使得電流控制振盪器10輸出的振盪頻率F_out 能夠不被製程變動、供應電壓變動和溫度飄移影響。Figure 3 is an embodiment of the invention depicting a current controlled oscillator 30 independent of process voltage temperature. The current controlled oscillator 30 independent of the process voltage temperature includes a temperature controller 31 (hereinafter abbreviated as T-controller 31), a process and voltage controller 32 (hereinafter abbreviated as PV-controller 32), and a current controlled oscillator. 10. In addition to providing voltage V _N1 to PV-controller 32, T-controller 31 also provides current I _M6 for sharing with PV-controller 32 and current-controlled oscillator 10. In addition, the T-controller 31 is used to prevent the current-controlled oscillator 10 from being affected by temperature drift, and the PV-controller 32 is used to prevent the current-controlled oscillator 10 from being affected by process and supply voltage variations, thus making the current-controlled oscillator The 10 output oscillation frequency F _out can be unaffected by process variations, supply voltage variations, and temperature drift.

第4圖所示之電路圖係為本發明中T-控制器之一實施例。T-控制器31包括能帶隙參考電路(bandgap circuit)310、第一調節器電路312、PMOS電晶體對314以及第二調節器電路316。能帶隙參考電路310產生不被PVT影響的第一能帶隙參考電壓V_N1 、反比於溫度的第二能帶隙參考電壓V_N4 (溫度越高，第二能帶隙參考電壓V_N4 越低)以及能帶隙參考電流I_N1 。第一調節器電路312包括運算大器、PMOS電晶體M₂ ，以及電阻器R₁ 。運算放大器具有第一輸入端、第二輸入端，以及輸出端。第一輸入端接收第二能帶隙參考電壓V_N4 。第二輸入端耦接至電阻器R₁ 的一端和PMOS電晶體M₂ 的汲極。運算放大器的輸出端耦接至PMOS電晶體M₂ 的閘極。PMOS電晶體M₂ 的源極耦接至電源供應端。電阻器R₁ 的另一端耦接至接地端。PMOS電晶體對314具有PMOS電晶體M₄ 和PMOS電晶體M₃ 。PMOS電晶體M₄ 具有閘極耦接至能帶隙參考電路310之PMOS電晶體M₁ 的閘極，PMOS電晶體M₄ 的源極耦接至電源供應端，以及汲極。PMOS電晶體M₃ 具有閘極耦接至第一調節器電路312之PMOS電晶體M₂ 的閘極，PMOS電晶體M₃ 的源極耦接至電源供應端，以及汲極耦接至PMOS電晶體M₄ 的汲極。第二調節器電路316包括電阻器R₂ 、運算放大器、PMOS電晶體M₅ 、PMOS電晶體M₆ ，以及外部的電阻器R_ext 。電阻器R₂ 具有第一端耦接至PMOS電晶體對314，以及第二端耦接至接地端。運算放大器具有第一輸入端耦接至電阻器R₂ 的第一端、第二輸入端，以及輸出端。PMOS電晶體M₅ 具有閘極耦接至運算放大器的輸出端、源極耦接至電源供應端，以及汲極耦接至運算放大器的第二輸入端。PMOS電晶體M₆ 具有閘極耦接至PMOS電晶體M₅ 的閘極、源極耦接至電源供應端，以及汲極耦接至電流控制振盪器10和PV-控制器32。高精度之外部的電阻器R_ext 耦接於PMOS電晶體M₅ 的汲極和接地端之間。The circuit diagram shown in Fig. 4 is an embodiment of the T-controller of the present invention. The T-controller 31 includes a bandgap circuit 310, a first regulator circuit 312, a PMOS transistor pair 314, and a second regulator circuit 316. The bandgap reference circuit 310 generates a first PVT not affect the bandgap reference voltage V _N1, inversely proportional to the temperature of a second bandgap reference voltage V _N4 (the higher the temperature, a second bandgap reference voltage V _N4 more Low) and the bandgap reference current I _N1 . The first regulator circuit 312 includes an arithmetic amplifier, a PMOS transistor M ₂ , and a resistor R ₁ . The operational amplifier has a first input, a second input, and an output. The first input receives the second energy bandgap reference voltage V _N4 . The second input terminal is coupled to one end of the resistor R ₁ and the drain of the PMOS transistor M ₂ . The output of the operational amplifier is coupled to the gate of the PMOS transistor M ₂ . The source of the PMOS transistor M ₂ is coupled to the power supply terminal. The other end of the resistor R ₁ is coupled to the ground. The PMOS transistor pair 314 has a PMOS transistor M ₄ and a PMOS transistor M ₃ . The PMOS transistor M ₄ has a gate whose gate is coupled to the PMOS transistor M ₁ of the band gap reference circuit 310, the source of the PMOS transistor M ₄ is coupled to the power supply terminal, and the drain. The PMOS transistor M ₃ has a gate coupled to the gate of the PMOS transistor M ₂ of the first regulator circuit 312, the source of the PMOS transistor M ₃ is coupled to the power supply terminal, and the drain is coupled to the PMOS transistor The drain of the crystal M ₄ . The second regulator circuit 316 includes a resistor R ₂ , an operational amplifier, a PMOS transistor M ₅ , a PMOS transistor M ₆ , and an external resistor R _ext . The resistor R ₂ has a first end coupled to the PMOS transistor pair 314 and a second end coupled to the ground. The operational amplifier has a first input coupled to the first end of the resistor R ₂ , a second input, and an output. The PMOS transistor M ₅ has a gate coupled to the output of the operational amplifier, a source coupled to the power supply, and a second input coupled to the operational amplifier. The PMOS transistor M ₆ has a gate coupled to the gate of the PMOS transistor M ₅ , a source coupled to the power supply terminal, and a drain coupled to the current controlled oscillator 10 and the PV controller 32 . A high-precision external resistor R _{ext is} coupled between the drain of the PMOS transistor M ₅ and the ground.

在能帶隙參考電路310中，若電壓V_N2 等於第二能帶隙參考電壓V_N4 ，則應滿足下列方程式：In the bandgap reference circuit 310, if the voltage V _N2 is equal to the second bandgap reference voltage V _N4 , the following equation should be satisfied:

I_MA ‧R_A +V_EB1 =V_EB2 I _MA ‧R _A +V _EB1 =V _EB2

因此，therefore,

I_MA ‧R_A =V_EB1 -V_EB2 I _MA ‧R _A =V _EB1 -V _EB2

其中，among them,

所以，and so,

I_MA ‧R_A =V_T ln(n)。I _MA ‧R _A =V _T ln(n).

根據上述推導，若三個MOS電晶體M_A 、M_B 和M₁ 均相同，則：According to the above derivation, if the three MOS transistors M _A , M _B and M ₁ are the same, then:

其中，能帶隙參考電流I_N1 為(V_T ln(n)/R_A )，且與溫度成正比。因為PMOS電晶體M₁ 的閘極連接於PMOS電晶體M₄ 的閘極，且PMOS電晶體M₁ 的源極連接於PMOS電晶體M₄ 的源極，所以PMOS電晶體M₄ 上的電流I_M4 是能帶隙參考電流I_N1 之鏡射電流。鏡射的電流I_M4 不一定等於能帶隙參考電流I_N1 ，需視PMOS電晶體M₁ 和M₄ 的寬長比(length-to-width ratio)而定。在此處，因為能帶隙參考電流I_N1 與溫度成正比，所以電流I_M4 亦與溫度成正比。此外，第一調節器電路312接收第二能帶隙參考電壓V_N4 並產生調節器電流I_R1 ，其中調節器電流I_R1 等於第二能帶隙參考電壓V_N4 除以電阻器R₁ (即V_N4 /R₁ )。因為PMOS電晶體M₂ 的閘極連接於PMOS電晶體M₃ 的閘極，且PMOS電晶體M₂ 的源極亦連接於PMOS電晶體M₃ 的源極，所以PMOS電晶體M₃ 上的電流I_M3 是調節器電流I_R1 的鏡射電流。鏡射的電流I_M3 不一定等於調節器電流I_R1 ，需視PMOS電晶體M₂ 和M₃ 的寬長比而定。在此處，因為第二能帶隙參考電壓V_N4 與溫度成反比，所以電流I_M3 亦與溫度成反比。電流I_M3 和I_M4 形成一暫時總電流I_temp 。暫時總電流I_temp 用以補償電流控制振盪器10之非理想的溫度效應。舉例而言，藉由合適地選擇電阻器R₁ 的數值，當電流控制振盪器10的振盪頻率隨著溫度增加而減少時(如第2圖所示)，暫時總電流I_temp 會隨之增加，因此能夠提供更大的電流I_M6 至電流控制振盪器10(原因如後詳述)。因為提供了更大的電流，所以電流控制振盪器10的振盪頻率也更高，溫度飄移造成的共振頻率的降低藉此得到補償。Wherein, the bandgap reference current I _N1 is (V _T ln(n)/R _A ) and is proportional to the temperature. Because the PMOS transistor M gate ₁ is connected to the gate PMOS transistor M ₄ of the pole, and the PMOS transistor M source ₁ is connected to a source of the PMOS transistor M ₄ pole, so that the current I on the PMOS transistor M ₄ _M4 is the mirror current of the bandgap reference current I _N1 . The mirrored current I _{M4 is} not necessarily equal to the band gap reference current I _N1 , depending on the length-to-width ratio of the PMOS transistors M ₁ and M ₄ . Here, since the bandgap reference current I _N1 is proportional to the temperature, the current I _{M4 is} also proportional to the temperature. Furthermore, the first regulator circuit 312 receives the second bandgap reference voltage V _N4 and produces a regulator current I _R1 , wherein the regulator current I _R1 is equal to the second band gap reference voltage V _N4 divided by the resistor R ₁ (ie V _N4 /R ₁ ). Because the gate PMOS transistor M ₂ is connected to the gate PMOS transistor M ₃ of the pole, and the PMOS transistor M source ₂ electrode is also connected to a source of the PMOS transistor M ₃ of the pole, so that the current _{on. 3} PMOS transistor M I _M3 is the mirror current of the regulator current I _R1 . The mirrored current I _{M3 is} not necessarily equal to the regulator current I _R1 , depending on the aspect ratio of the PMOS transistors M ₂ and M ₃ . Here, since the second band gap reference voltage V _N4 is inversely proportional to the temperature, the current I _{M3 is} also inversely proportional to the temperature. Currents I _M3 and I _M4 form a temporary total current I _temp . The temporary total current I _{temp is} used to compensate for the non-ideal temperature effects of the current controlled oscillator 10. For example, by appropriately selecting the value of the resistor R ₁ , when the oscillation frequency of the current-controlled oscillator 10 decreases as the temperature increases (as shown in FIG. 2 ), the temporary total current I _temp increases. Therefore, a larger current I _M6 can be supplied to the current controlled oscillator 10 (for reasons as described later). Since a larger current is supplied, the oscillation frequency of the current-controlled oscillator 10 is also higher, and the decrease in the resonance frequency caused by the temperature drift is thereby compensated.

然而，由於電阻器的公差(tolerance)(電阻器的公差可能高達20%)，暫時總電流I_temp 可能隨之變動。有鑒於此，故在第二調節器電路316中使用高精度的外部的電阻器R_ext ，如下所述。However, due to the tolerance of the resistor (the tolerance of the resistor may be as high as 20%), the temporary total current I _temp may vary accordingly. In view of this, a high-precision external resistor R _ext is used in the second regulator circuit 316 as described below.

第二調節器電路316由PMOS電晶體對314接收暫時總電流I_temp ，並在運算放大器的輸入端產生電壓V_R2 。因此，在外部的電阻器R_ext 上會產生等於電壓V_R2 的電壓V_Rext 。因為外部的電阻器R_ext 為高精度的電阻器(high-precision resistor)，具有極小的誤差，所以在外部的電阻器R_ext 上的電流I_Rext 的變動也很小。此外，因為PMOS電晶體M₅ 的閘極亦連接於PMOS電晶體M₆ 的閘極，且PMOS電晶體M₅ 的源極亦連接於PMOS電晶體M₆ 的源極，所以PMOS電晶體M₆ 上的電流I_M6 是電流I_Rext 的鏡射電流。鏡射的電流I_M6 不一定等於電流I_Rext ，需視PMOS電晶體M₅ 和M₆ 的寬長比而定。電流I_M6 是最終輸出的輸出電流，並且由電流控制振盪器10與PV-控制器32一同共享。The second regulator circuit 316 receives the temporary total current I _temp from the PMOS transistor pair 314 and produces a voltage V _R2 at the input of the operational amplifier. Therefore, a voltage V _Rext equal to the voltage V _R2 is generated on the external resistor R _ext . Since the external resistor R _ext is a high-precision resistor with a small error, the variation of the current I _Rext on the external resistor R _ext is also small. In addition, since the gate of the PMOS transistor M ₅ is also connected to the gate of the PMOS transistor M ₆ and the source of the PMOS transistor M ₅ is also connected to the source of the PMOS transistor M ₆ , the PMOS transistor M ₆ The current I _M6 is the mirror current of the current I _Rext . The mirrored current I _{M6 is} not necessarily equal to the current I _Rext and depends on the aspect ratio of the PMOS transistors M ₅ and M ₆ . The current I _M6 is the output current of the final output and is shared by the current controlled oscillator 10 together with the PV-controller 32.

目前為止已經說明T-控制器31如何避免受到溫度漂移的影響。接下來的實施例將說明PV-控制器32如何避免受到製程和供應電壓變動的影響。It has been explained so far how the T-controller 31 is protected from temperature drift. The next embodiment will illustrate how the PV-controller 32 is protected from variations in process and supply voltage.

第5A圖所示之電路圖為本發明中PV-控制器之一實施例。PV控制器32包括第三調節器電路320和調整電路322。第三調節器電路320包括運算放大器、PMOS電晶體，以及電阻器R₃ 。運算放大器具有第一輸入端以接收第一能帶隙參考電壓V_N1 、第二輸入端，以及輸出端。PMOS電晶體具有閘極耦接至運算放大器的輸出、源極耦接至電源供應端，以及汲極耦接至運算放大器的第二輸入端。電阻器R₃ 耦接於PMOS電晶體的汲極與接地端間。如第5A圖所示，調整電路322包括PMOS電晶體M₇ 、NMOS電晶體M₈ ，以及電流鏡。PMOS電晶體M₇ 具有源極耦接至第一能帶隙參考電壓V_N1 ，以及閘極耦接至電阻器R₃ 。電流鏡耦接至PMOS電晶體M₇ 。NMOS電晶體M₈ 具有汲極耦接至電流I_M6 流經的節點N_X 、閘極耦接至電阻器R₃ ，以及源極耦接至接地端。The circuit diagram shown in Fig. 5A is an embodiment of the PV-controller of the present invention. The PV controller 32 includes a third regulator circuit 320 and an adjustment circuit 322. Third regulator circuit includes an operational amplifier 320, the PMOS transistor, and a resistor R _3. The operational amplifier has a first input to receive a first energy bandgap reference voltage V _N1 , a second input, and an output. The PMOS transistor has a gate coupled to the output of the operational amplifier, a source coupled to the power supply terminal, and a drain coupled to the second input of the operational amplifier. The resistor R _{3 is} coupled between the drain of the PMOS transistor and the ground. , The adjusting circuit 322 comprises a PMOS transistor M _7, NMOS transistor M _8, as in the first current mirror 5A and FIG. The PMOS transistor M ₇ has a source coupled to the first bandgap reference voltage V _N1 and a gate coupled to the resistor R ₃ . The current mirror is coupled to the PMOS transistor M ₇ . The NMOS transistor M ₈ has a node N _X through which the drain is coupled to the current I _M6 , a gate coupled to the resistor R ₃ , and a source coupled to the ground.

調整電路322的元件需視電流控制振盪器10內元件的形式而定。具體而言，電流控制振盪器10可能僅包括PMOS或NMOS電晶體，或同時包括PMOS和NMOS電晶體。如第5B圖所示，若電流控制振盪器10僅包括PMOS電晶體，則調整電路322必須包括相應的PMOS電晶體M7。如第5C圖所示，若電流控制振盪器10僅包括NMOS電晶體，則調整電路322必須包括相應的NMOS電晶體M₈ 。如第5A圖所示，類似地，若電流控制振盪器10同時包括PMOS和NMOS電晶體，則調整電路322必須同時包括相應的PMOS和NMOS電晶體M₇ 和M₈ 。參考第5A圖，PV-控制器32接受由T-控制器31提供的第一能帶隙參考電壓V_N1 。因為第一能帶隙參考電壓V_N1 不會被PVT和電阻器公差所影響，所以第一能帶隙參考電壓V_N1 除以電阻器R₃ 也不會被PVT和公差所影響。這提供了穩定的電壓差於PMOS電晶體M₇ 的閘極和源極間(即V_SG )。因此，PMOS電晶體M₇ 上的電流I_M7 便不會受到供應電源變動的影響(若PMOS電晶體M₇ 連接至作為供應電源的一個供應電壓，則PMOS電晶體M₇ 上的電流會受到供應電壓變動的影響)。根據相同的原理，介於NMOS電晶體M₈ 閘極和源極間的電壓差(即V_GS )也是穩定的。The components of the adjustment circuit 322 are dependent on the form of the components within the current controlled oscillator 10. In particular, current controlled oscillator 10 may include only PMOS or NMOS transistors, or both PMOS and NMOS transistors. As shown in FIG. 5B, if the current controlled oscillator 10 includes only PMOS transistors, the adjustment circuit 322 must include a corresponding PMOS transistor M7. As shown on FIG. 5C, only when the current-controlled oscillator 10 comprises an NMOS transistor, the adjusting circuit 322 must include a respective NMOS transistor M _8. As shown in FIG. 5A, similarly, if the current controlled oscillator 10 includes both the PMOS and NMOS transistors, the adjusting circuit 322 must also comprise a respective PMOS transistor M ₇ and the NMOS and M _8. Referring first to FIG 5A, PV- controller 32 receives the first controller can be provided by a T- 31 bandgap reference voltage V _N1. Since the first bandgap reference voltage V _{N1 is} not affected by the PVT and resistor tolerances, the first bandgap reference voltage V _N1 divided by the resistor R ₃ is not affected by the PVT and tolerance. This provides a stable voltage difference between the electrodes (i.e., V _SG) of the PMOS transistor M ₇ of the gate and the source. Therefore, the current I _M7 on the PMOS transistor M ₇ is not affected by the variation of the power supply (if the PMOS transistor M _{7 is} connected to a supply voltage as a supply source, the current on the PMOS transistor M ₇ is supplied. The effect of voltage fluctuations). According to the same principle, the voltage difference (i.e., V _GS ) between the gate and the source of the NMOS transistor M ₈ is also stable.

因此，上述即為PV-控制器32如何避免電流控制振盪器10受到供應電壓變動的影響。接著的實施例將說明PV-控制器32如何避免電流控制振盪器32受到製程變動的影響。考慮以下公式：Therefore, the above is how the PV-controller 32 prevents the current-controlled oscillator 10 from being affected by variations in the supply voltage. The following embodiment will illustrate how the PV-controller 32 avoids the current controlled oscillator 32 from being affected by process variations. Consider the following formula:

對PMOS電晶體M₇ 而言， For PMOS transistor M ₇ ,

對NMOS電晶體M₈ 而言， For the NMOS transistor M ₈ ,

根據第5A圖的電路，PMOS和NMOS電晶體M₇ 和M₈ 的閘源電壓(V_GS )不會被PVT和電阻器公差所影響。因此，電流I_M7 和I_M8 與其臨界電壓(V_TH )有關。臨界電壓的大小與MOS電晶體的製程變動有關。當製程邊界F(corner=F)的製程變動造成電流控制振盪器10的振盪頻率高於既定頻率(頻率變動)時，電流I_M7 /I_M8 也會比較大。這是因為製程邊界F的製程變動代表臨界電壓V_TH 比較小，而比較小的臨界電壓V_TH 造成比較大的電流I_M7 /I_M8 ，其中電流I_M7 /I_M8 是由電流I_M6 的分支電流。由於由電流I_M6 分支出來的電流I_M7 /I_M8 比較大，提供至電流控制振盪器10的電流也比較小，因而降低電流控制振盪器10的振盪頻率。因為PV-控制器32和電流控制振盪器10均使用同型的MOS電晶體(P型或N型電晶體)，所以在PV-控制器32和電流控制振盪器10內電晶體的製程變動也都是在製程邊界F。上述即為PV-控制器32如何避免電流控制振盪器32受到製程變動之影響的說明。According to the circuit of Figure 5A, the gate voltages (V _GS ) of the PMOS and NMOS transistors M ₇ and M ₈ are not affected by the PVT and resistor tolerances. Therefore, the currents I _M7 and I _{M8 are} related to their threshold voltage (V _TH ). The magnitude of the threshold voltage is related to the process variation of the MOS transistor. When the process variation of the process boundary F (corner=F) causes the oscillation frequency of the current-controlled oscillator 10 to be higher than a predetermined frequency (frequency variation), the current I _M7 /I _{M8 is} also large. This is because the process variation of the process boundary F represents that the threshold voltage V _{TH is} relatively small, and the relatively small threshold voltage V _TH causes a relatively large current I _M7 /I _M8 , wherein the current I _M7 /I _M8 is a branch of the current I _M6 Current. Since the current I _M7 /I _M8 branched by the current I _{M6 is} relatively large, the current supplied to the current controlled oscillator 10 is also relatively small, thereby reducing the oscillation frequency of the current controlled oscillator 10. Since both the PV-controller 32 and the current-controlled oscillator 10 use the same type of MOS transistor (P-type or N-type transistor), the process variations of the transistors in the PV-controller 32 and the current-controlled oscillator 10 are also Is at the process boundary F. The above is a description of how the PV-controller 32 avoids the influence of the current-controlled oscillator 32 on process variations.

雖然本發明以較佳實施例揭露如上，但並非用以限制本發明。相對地，習知技藝者應能知悉能夠將本發明的概念延伸推廣至多種變型與相似的設置。因此，申請專利範圍的範疇應以本發明之多種變型與相似的設置為考量依據。While the invention has been described above in the preferred embodiments, it is not intended to limit the invention. In contrast, the skilled artisan will be able to appreciate that the concept of the invention can be extended to a variety of variations and similar arrangements. Therefore, the scope of the patent application scope should be considered in view of various modifications and similar arrangements of the present invention.

10‧‧‧電流控制振盪器10‧‧‧ Current Controlled Oscillator

F_out ‧‧‧振盪頻率F _out ‧‧‧Oscillation frequency

V_DD ‧‧‧供應電壓V _DD ‧‧‧ supply voltage

I_c ‧‧‧電流源I _c ‧‧‧current source

30‧‧‧電流控制振盪器30‧‧‧ Current Controlled Oscillator

31‧‧‧T-控制器31‧‧‧T-controller

32‧‧‧PV-控制器32‧‧‧PV-controller

N_X ‧‧‧節點N _X ‧‧‧ nodes

V_N1 、V_N2 、V_N4 、V_R2 、V_Rext ‧‧‧電壓V _N1 , V _N2 , V _N4 , V _R2 , V _Rext ‧‧‧ voltage

I_M6 、I_MA 、I_N1 、I_M3 、I_M4 、I_R1 、I_M6 、I_M7 、I_M8 、I_Rext ‧‧‧電流I _M6 , I _MA , I _N1 , I _M3 , I _M4 , I _R1 , I _M6 , I _M7 , I _M8 , I _Rext ‧‧‧ Current

R_A 、R_B 、R₁ 、R₂ 、R₃ 、R_ext ‧‧‧電阻器R _A , R _B , R ₁ , R ₂ , R ₃ , R _ext ‧‧‧ resistors

310‧‧‧能帶隙參考電路310‧‧‧ Bandgap reference circuit

312‧‧‧第一調節器電路312‧‧‧First regulator circuit

314‧‧‧PMOS對314‧‧‧ PMOS pair

316‧‧‧第二調節器電路316‧‧‧Second regulator circuit

320‧‧‧第三調節器電路320‧‧‧ Third regulator circuit

322‧‧‧調整電路322‧‧‧Adjustment circuit

Q₁ 、Q₂ 、Q₃ 、M_A 、M_B 、M₁ -M₈ ‧‧‧電晶體Q ₁ , Q ₂ , Q ₃ , M _A , M _B , M ₁ -M ₈ ‧‧‧O crystal

本發明能夠以實施例伴隨所附圖式而被理解，其中：第1圖為電流控制振盪器的圖示；第2圖為電流控制振盪器的特徵曲線；第3圖為本發明實施例之與製程-電壓-溫度(PVT)無關的電流控制振盪器；第4圖為本發明實施例之溫度控制器(T-控制器)的電路圖；第5A圖為本發明實施例之製程和電壓控制器(PV-控制器)的完整電路圖；第5B圖為本發明實施例部份之PV-控制器的部份電路圖；第5C圖為本發明另一實施例部份之PV-控制器的部份電路圖。The present invention can be understood by the accompanying drawings in which: FIG. 1 is a diagram of a current controlled oscillator; FIG. 2 is a characteristic curve of a current controlled oscillator; FIG. 3 is an embodiment of the present invention a current controlled oscillator independent of process-voltage-temperature (PVT); FIG. 4 is a circuit diagram of a temperature controller (T-controller) according to an embodiment of the present invention; and FIG. 5A is a process and voltage control according to an embodiment of the present invention A complete circuit diagram of a PV-controller; FIG. 5B is a partial circuit diagram of a PV-controller according to an embodiment of the present invention; FIG. 5C is a diagram of a portion of a PV-controller according to another embodiment of the present invention. Circuit diagram.

10．．．電流控制振盪器10. . . Current controlled oscillator

F_out ．．．振盪頻率F _out . . . Oscillating frequency

30．．．電流控制振盪器30. . . Current controlled oscillator

31．．．T-控制器31. . . T-controller

32．．．PV-控制器32. . . PV-controller

V_N1 ．．．電壓V _N1 . . . Voltage

I_M6 ．．．電流I _M6 . . . Current

Claims

一種與製程-電壓-溫度(PVT)無關的電流控制振盪器，包括：一製程和電壓控制器，根據製程以及電壓而改變流經上述製程和電壓控制器的電流；一電流控制振盪器，耦接至上述製程和電壓控制器，用以輸出一振盪頻率；以及一溫度控制器，耦接至上述製程和電壓控制器和上述電流控制振盪器，用以提供一總電流予上述製程和電壓控制器和上述電流控制振盪器一同共享，並且根據溫度而改變流經上述溫度控制器的電流，其中若上述電流控制振盪器因一製程變動而使上述振盪頻率高於一既定頻率時，則上述製程和電壓控制器藉由增加上述製程和電壓控制器的電流，減少上述電流控制振盪器的電流，並且若上述電流控制振盪器因上述製程變動而使上述振盪頻率低於上述既定頻率時，則上述製程和電壓控制器藉由減少上述製程和電壓控制器的電流，增加上述電流控制振盪器的電流，藉此動態地調整上述振盪頻率。 A process-voltage-temperature (PVT) independent current controlled oscillator comprising: a process and voltage controller that varies current flowing through the process and voltage controllers according to process and voltage; a current controlled oscillator, coupled Connected to the process and voltage controller for outputting an oscillation frequency; and a temperature controller coupled to the process and voltage controller and the current control oscillator to provide a total current to the process and voltage control And sharing the current control oscillator together, and changing the current flowing through the temperature controller according to the temperature, wherein if the current control oscillator changes the oscillation frequency to be higher than a predetermined frequency due to a process variation, the process And the voltage controller reduces the current of the current control oscillator by increasing the current of the process and the voltage controller, and if the current control oscillator causes the oscillation frequency to be lower than the predetermined frequency due to the process variation, Process and voltage controllers increase the above by reducing the current of the above process and voltage controller The current is controlled by the current of the oscillator, whereby the above oscillation frequency is dynamically adjusted.

如申請專利範圍第1項所述之與製程-電壓-溫度(PVT)無關的電流控制振盪器，其中上述溫度控制器包括：一能帶隙參考電路，用以產生一第一能帶隙參考電壓、一第二能帶隙參考電壓以及一能帶隙參考電流，其中上述第一能帶隙參考電壓用以產生上述能帶隙參考電流；一第一調節器電路，用以根據上述第二能帶隙參考電壓而產生一調節器電流；一PMOS電晶體對，用以根據上述調節器電流和上述能帶隙參考電流而產生一暫時總電流；以及一第二調節器電路，用以根據上述暫時總電流而產生上述總電流。 The process-voltage-temperature (PVT)-independent current controlled oscillator of claim 1, wherein the temperature controller comprises: an energy bandgap reference circuit for generating a first band gap reference a voltage, a second bandgap reference voltage, and an energy bandgap reference current, wherein the first bandgap reference voltage is used to generate the bandgap reference current; and a first regulator circuit is configured to Bandgap reference Pressing to generate a regulator current; a PMOS transistor pair for generating a temporary total current according to the regulator current and the band gap reference current; and a second regulator circuit for determining the temporary total current The above total current is generated.

如申請專利範圍第2項所述之與製程-電壓-溫度(PVT)無關的電流控制振盪器，其中上述製程和電壓控制器包括：一第三調節器電路，用以接受上述第一能帶隙參考電壓，並將上述第一能帶隙參考電壓分成一分壓；以及一調整電路，耦接至上述第三調節器電路，用以接收上述總電流，並根據上述分壓而調整上述製程和電壓控制器由上述總電流所分享到的電流大小。 A process-voltage-temperature (PVT)-independent current controlled oscillator as described in claim 2, wherein the process and voltage controller comprises: a third regulator circuit for accepting the first energy band a reference voltage, and dividing the first energy bandgap reference voltage into a partial voltage; and an adjusting circuit coupled to the third regulator circuit for receiving the total current, and adjusting the process according to the voltage division And the magnitude of the current that the voltage controller is shared by the total current described above.

如申請專利範圍第3項所述之與製程-電壓-溫度(PVT)無關的電流控制振盪器，其中當上述電流控制振盪器係由PMOS電晶體所構成時，上述調整電路包括：一第一PMOS電晶體，具有一源極耦接至上述第一能帶隙參考電壓，以及一閘極耦接至上述分壓；以及一電流鏡，耦接至上述第一PMOS電晶體，其中當上述第一PMOS電晶體的電流增加時，上述製程和電壓控制器由上述總電流所分享到的電流大小也增加；並且當上述第一PMOS電晶體的電流減少時，上述製程和電壓控制器由上述總電流所分享到的電流大小也減少。 A process-voltage-temperature (PVT)-independent current-controlled oscillator as described in claim 3, wherein when the current-controlled oscillator is composed of a PMOS transistor, the adjustment circuit includes: a first a PMOS transistor having a source coupled to the first bandgap reference voltage and a gate coupled to the voltage divider; and a current mirror coupled to the first PMOS transistor, wherein When the current of a PMOS transistor increases, the magnitude of the current shared by the above process and voltage controller by the total current also increases; and when the current of the first PMOS transistor decreases, the process and voltage controller are total The amount of current shared by the current is also reduced.

如申請專利範圍第3項所述之與製程-電壓-溫度 (PVT)無關的電流控制振盪器，其中當上述電流控制振盪器係由NMOS電晶體所構成時，上述調整電路包括：一第一NMOS電晶體，具有一汲極耦接至上述總電流、一閘極耦接至上述分壓，以及一源極耦接至一接地端，其中當上述第一NMOS電晶體的電流增加時，上述製程和電壓控制器由上述總電流所分享到的電流大小也增加；並且當上述第一NMOS電晶體的電流減少時，上述製程和電壓控制器由上述總電流所分享到的電流大小也減少。 Process-voltage-temperature as described in item 3 of the patent application scope a (PVT)-independent current-controlled oscillator, wherein when the current-controlled oscillator is composed of an NMOS transistor, the adjustment circuit includes: a first NMOS transistor having a drain coupled to the total current, and a a gate is coupled to the voltage dividing portion, and a source is coupled to a ground terminal, wherein when the current of the first NMOS transistor is increased, the current amount shared by the process and the voltage controller by the total current is also Increasing; and when the current of the first NMOS transistor is reduced, the magnitude of the current shared by the process and voltage controller from the total current is also reduced.

如申請專利範圍第3項所述之與製程-電壓-溫度(PVT)無關的電流控制振盪器，其中第三調節器電路包括：一運算放大器，具有一第一輸入端用以接收上述第一能帶隙參考電壓、一第二輸入端，以及一輸出端；一PMOS電晶體具有一閘極耦接至上述運算放大器的上述輸出端、一源極耦接至一電源供應端，以及一汲極耦接至上述第二輸入端；以及一電阻器耦接於上述PMOS電晶體的汲極與一接地端間。 A process-voltage-temperature (PVT)-independent current controlled oscillator as described in claim 3, wherein the third regulator circuit comprises: an operational amplifier having a first input for receiving the first a bandgap reference voltage, a second input terminal, and an output terminal; a PMOS transistor having a gate coupled to the output terminal of the operational amplifier, a source coupled to a power supply terminal, and a stack The pole is coupled to the second input end; and a resistor is coupled between the drain of the PMOS transistor and a ground.

如申請專利範圍第2項所述之與製程-電壓-溫度(PVT)無關的電流控制振盪器，其中上述第一調節器電路包括：一運算放大器，具有一第一輸入端用以接收上述第二能帶隙參考電壓、一第二輸入端，以及一輸出端；一PMOS電晶體具有一閘極耦接至上述運算放大器的上述輸出端、一源極耦接至一電源供應端，以及一汲極耦接至上述第二輸入端；以及一電阻器耦接於上述PMOS電晶體的汲極與一接地端間，其中上述第一調節器電流的大小等於上述第二能帶隙參考電壓除以上述電阻器的電阻值。 A process-voltage-temperature (PVT)-independent current controlled oscillator as described in claim 2, wherein the first regulator circuit comprises: an operational amplifier having a first input for receiving the first a second bandgap reference voltage, a second input terminal, and an output terminal; a PMOS transistor having a gate coupled to the operational amplifier The output terminal and the source are coupled to a power supply terminal, and a drain is coupled to the second input terminal; and a resistor is coupled between the drain of the PMOS transistor and a ground terminal, wherein the The magnitude of the first regulator current is equal to the second energy bandgap reference voltage divided by the resistance value of the resistor.

如申請專利範圍第2項所述之與製程-電壓-溫度(PVT)無關的電流控制振盪器，其中上述PMOS電晶體對包括：一第一PMOS電晶體，具有一第一閘極耦接至上述能帶隙參考電路、一第一源極耦接至一電源供應端，以及一第一汲極；以及一第二PMOS電晶體，具有一第二閘極耦接至上述第一調節器電路、一第二源極耦接至上述電源供應端，以及一第二汲極耦接至上述第一汲極。 The process-voltage-temperature (PVT)-independent current-controlled oscillator of claim 2, wherein the PMOS transistor pair comprises: a first PMOS transistor having a first gate coupled to The energy band gap reference circuit, the first source is coupled to a power supply terminal, and a first drain; and a second PMOS transistor having a second gate coupled to the first regulator circuit A second source is coupled to the power supply terminal, and a second drain is coupled to the first drain.

如申請專利範圍第2項所述之與製程-電壓-溫度(PVT)無關的電流控制振盪器，其中上述第二調節器電路包括：一電阻器，具有一第一端耦接至上述PMOS電晶體對，以及一第二端耦接至一接地端；一運算放大器，具有一第一輸入端耦接至上述電阻器的上述第一端、一第二輸入端，以及一輸出端；一第一PMOS電晶體，具有一第一閘極耦接至上述輸出端、一第一源極耦接至一電源供應端，以及一第一汲極耦接至上述第二輸入端；一第二PMOS電晶體，用以提供上述總電流，具有一第二閘極耦接至上述第一閘極、一第二源極耦接至上述電源供應端，以及一第二汲極耦接至上述電流控制振盪器和上述製程和電壓控制器；以及一高精度的電阻器，耦接於上述第一汲極和上述接地端間。 The process-voltage-temperature (PVT)-independent current-controlled oscillator of claim 2, wherein the second regulator circuit comprises: a resistor having a first end coupled to the PMOS a pair of crystals, and a second end coupled to a ground; an operational amplifier having a first input coupled to the first end of the resistor, a second input, and an output; a PMOS transistor having a first gate coupled to the output terminal, a first source coupled to a power supply terminal, and a first drain coupled to the second input terminal; a second PMOS transistor for providing the total current, having a second gate coupled to the first gate, a second source coupled to the power supply terminal, and a second drain coupled And the current control oscillator and the process and voltage controller; and a high precision resistor coupled between the first drain and the ground.