M3 02193 八、新型說明： 【新型所屬之技術領域】 本創作提供一種電壓調節電路，尤指一種避免輸入電壓突降 的電壓調節電路。 【先前技術】 一般而言，電壓調節電路係串聯於輸入電壓訊號與輸出電壓 籲訊號之間，其功能類似於一個電壓源，用以將輸入電壓訊號轉換 為輸出電壓訊號，並提供輸出電壓訊號一個穩定的電壓準位。 在此請參照第1圖，第1圖係習知電壓調節器10〇的電路示 意圖。此電壓調節器100包含有一電晶體Q1、一回授電路1〇2、 一誤差放大器OP1以及一致能電路110，電晶體Q1可以為N型 場效電晶體(N-MOSFET)或P型場效電晶體(p_M〇SFET)或雙载 鲁子接面電晶體(BJT)。第1圖電晶體Qj係為p型場效電晶體 (P_MOSFET)，其源極(source)與汲極(drain)分別耦接於輸入電壓訊 號Vin以及輸出電壓訊號Vout，亦即電晶體Q1串聯於輸入電壓訊 说Vin以及輸出電壓訊號v〇ut之間，另外，電晶體…的没極雛 於回授電路102，藉由電阻Ri、R2的分壓電路造成回授電路搬 產生一回授電壓訊號，並將回授電壓訊號送至誤差放大器 0P1的非反相輸入端；此外，對於誤差放大器0P1而言，其非反 相輸入端祕於喊電壓魏Vfb、反她人端觖財考電壓訊 旒vref以及另有-啟動接腳連接概能電路11〇,其中致能電路⑽ 5 M3 02193 係依據一啟動控制訊號εν來控制控制誤差放大器OP1是否開始 運作，亦即控制此電壓調節器1〇〇是否啟動，舉例來說，若啟動 控制訊號EN由低邏輯準位，〇,轉變成高邏輯準位，丨，，則致能電路 110便會驅使誤差放大器OP1開始運作。誤差放大器〇p]l的輸出 端耦接於電晶體Q1的閘極，藉由此控制電壓訊號以控制電晶 體Q1的導通阻抗；因為誤差放大器0P1在整個電路中的角色係 作為一誤差放大器，換句話說，控制電壓訊號將反應回授電 ♦壓訊號與參考電壓訊號Vref之間的差異，用以調整電晶體Qi 的導通阻抗，因此輸出電壓訊號v〇ut最後便可以穩壓並且滿足下 列方程式(1): — * ^ 方程式(1) 亦即電壓調節器100藉由上述方程式達到穩定地產生輸出電壓訊 號V〇ut予-負載104的目的。此外，於第）圖中，Cin與c⑽分別 代表輸入電容與輸出電容，用來分別穩定輸入電壓訊號Vin以及輸 出電壓峨vout，由於其運作與功能為業界所習知，故不另於此資 述。 σ月乡…、第2圖’第2圖為第1圖所示之電壓調節電路1〇〇的 ί作時f圖。假設輸人電壓訊號Vin係3.3伏特、提舒啟動後之 、壓調即電路1〇0的參考電壓訊號mu伏特，以及所要的 ^出電壓訊號vQUt為2.5伏特，因此.，便可依據上述參數來決定出 、R2的阻值以構成所要的回授電路⑽。如第2圖所示， 日、間T1時若將啟動控制訊號例錄邏輯準位轉變成高邏輯準 6 M302193 位’則電壓調節電路將開始運作，其令參考電壓訊號^由 於需要提供給其他線路使用，所以參考電壓訊號I需要很快地 到達預設值U5伏特，另外在時間们時，輸出電壓訊號v⑽的輸 出電壓是0伏特’因此回授賴峨％亦是Q伏特，結果誤差放 大器on的輸出電壓為低電壓而且電晶體切將位於導通區；此 時’輸入電壓訊號Vin (對應一輪入電流訊號D透過電晶體W 的導通電阻對輸出電容c〇ut充電’由於導通電阻很小(一般大約是 #毫I姆）輸入電壓机號Vin的瞬間電流值將會很大並達到電晶 體Q1的電流限制Ilimit，進一步說，若電壓調節電路励是應用在 手持式產品（例如手機，數位相機等），其輸入端通常是祕於電 池’㈣電池内部亦有其内阻，因此，此—瞬間大電流將造成輸 η "號Vln產生電壓突降(v〇ltagedr〇p);另外，若輸入電壓訊 號的突降現象過於嚴重，亦可能影響其他與電池連接的系統產 ^錯誤運作’而軸為了避免此嚴4的電壓突降現象可在電壓調 •節電路100的輪入端輕接一較大電容值之輸入電容Cin，但是為了 使用^有較大電容值的輸人電容Cin，絲必須仙較大面積，而 且也提高了整體成本。對於應用在手持式產品而言，這是明顯的 【新型内容】 ，因本創作之主要目的之一在於提供一種避免輸入電壓突降 之電壓調節電路1可具有較小的桃面積及較少的 決以上提到的問題。 M302193 根據本創作之專利申請範圍，係揭露一種電壓調節電路，用 來依據一輸入電壓訊號產生一輸出電壓訊號。該電壓調節電路包 含有·一軟啟動電路，用來提供一軟啟動電壓訊號；以及一電壓 凋郎器，耗接於該軟啟動電路、該輸入電壓訊號以及一參考電壓 訊號，用來選擇性地比較該軟啟動電壓訊號與該參考電壓訊號之 一與該輸出電壓訊號所對應之一回授電霍訊號以依據該輸入電壓 Φ訊號產生該輸出電壓訊號。 【實施方式】 在此請參照第3圖，第3圖是本創作電壓調節電路3〇〇之一 實施例的電路示意圖。如第3圖所示，電壓調節電路3〇〇包含有 一電壓調節器302以及一軟啟動(soft start)電路304，其中電壓調 節器302包含有一電晶體Q卜一回授電路303、一致能電路310 以及一誤差放大Is 0P2 ’其中電晶體Q1、回授電路303與致能電 鲁路310的結構與功能分別與第1圖所述之電晶體qi、回授電路1〇2 與致能電路110相同，故在此不贅述，此外，於第3圖中，Cin與 Cm分別代表輸入電容與輸出電容，用來分別穩定輸入電壓訊號 Vin以及輸出電壓訊號Vout，由於其運作與功能為業界所習知，亦 不另於此贅述。誤差放大器0P2係為一具有三輸入端的誤差放大 器，其非反相輸入端耦接於回授電壓訊號Vfb，而其兩反相輸入端 則分別粞接於軟啟動電壓訊號vss和參考電壓訊號vref，於本實施 例中，當電壓調節電路300啟動後，誤差放大器0P2可以選擇性 M302193 使用軟啟動電壓訊號Vss或參考電壓訊號U此電壓調節器3〇2 的工作原理與第1圖所示之電壓調節器100的工作原理類似，差 別在於電壓調節器302啟動後可以選擇軟啟動電壓訊號vss或參考 電壓訊號vrefs中之一以控制輸出電壓訊號L與輸入電壓訊號 Vin，因此，本實施例係定義一預定範圍，而當軟啟動電壓訊號V% 與參考電壓虎vref的電壓差落於該預定範圍内(亦即無論軟啟動 電壓峨^係小於或超過參考電壓訊號D時，通常預定範圍一 籲般是趨近於〇伏特，亦即希望軟啟動電壓訊號Vss在非常靠近參考 電壓吼號vref時，電壓調節電路3〇〇便由軟啟動電壓訊號Vss切換 至參考電壓訊號vref來利帛參考電壓訊號Vref以控制輸出至一負載 05的輸出電壓成號vout，請注意，上述預定範圍可依據設計需求 而加以叹疋’舉例來說，於本創作之一實施例中，當軟啟動電壓 訊號VSS等於參考電壓訊號^時，誤差放大器肥才會由軟啟動 電壓訊號vss切換至參考電壓訊號Vref。另外，誤差放大器⑽的 _ 1擇[生輕接功此可利用一多工器(mul如lexer)來加以實現，然而， 任何實現選擇性輕接的手段均屬本創作誤差放大器0P2之範嘴。 第3圖所不之軟啟動電路3〇4另包含有一電源流U、一電容 -重置電晶體Q2以及一重置控制電路遍，根據本創作之一 實蝴，f源流Iss_來提供—參考電流，㈣容&係作為充放 電使用，所以，當重置電晶體吸未導通時，電源流^對電容L 充電’因此軟啟動電壓訊號Vss的電壓準位將漸漸由接地電位（亦 即0伏特）而增高Γ若重置電晶體Q2導通時，則電源流U無法 M302193 再對電谷Css充電並且電容&將開始經由重置電晶體而放電， 因此軟啟魏壓減Vss的電鮮娜漸漸降低朗其霞準位 .等於接地電位（亦即0伏特）。此外，重置控制電路3〇6係用於決 .定重置電晶體Q2是否導通，於本實施例中，為了破保軟啟動電壓 訊號Vss於每次電壓調節電路3〇〇啟動時均對應至接地電位，因此 重置電晶體Q2的導通條件如下： * · . •(一)啟動控制訊號EN由高邏輯準位轉變至低邏輯準位而關閉 誤差放大器OP2的運作；或者 (二)誤差放大器OP2已由軟啟動電壓訊號Vss切換至參考電壓 訊號Vrcf。 若於誤差放大器OP2由軟啟動電壓訊號Vss切換至參考電壓 訊號Vref之前，啟動控制訊號EN由高邏輯準位轉變至低邏輯準位 •而關閉誤差放大器ΟΡ2的運作，則條件(一)可確保軟啟動電壓訊 號Vss於下次電壓調節電路300啟動前被重置；另一方面，當誤差 放大器OP2已由軟啟動電壓訊號Vss切換至參考電壓訊號Vref，此 時，軟啟動電壓訊號Vss不再被誤差放大器OP2所採用，因此重 置控制電路306便可允許導通重置電晶體Q2來重置軟啟動電壓訊 號Vss，於本創作之較佳實施例中，當誤差放大器OP2由軟啟動電 壓訊號Vss切換至參考電壓訊號Vref時，重置控制電路306便立即 導通重置電晶體Q2，然而，本創作並不以此為限。另外，當啟動 控制訊號EN由低邏輯準位轉變至高邏輯準位時，亦即電壓調節電 M302193 路300開始啟動時，重置控制電路3〇6則會控制重置電晶體⑶進 入非導通狀態。 HU#參照第4 ® ’第4 _為第3圖所示之電壓調節電路 300的操作時序圖。假設輸人電麗訊號Vin係為Μ伏特，另外， 提供予電壓觸ϋ 的參考電舰號U為.丨Μ伏特以及所要 的輪出電壓讀V〇ut為Μ伏特，因此，便可依據上述參數來決定 φ出電阻Rl、R2的阻值以構成所要的回授電路3〇3。若在時間 時將啟動控觀號EN由低邏輯準轉換為高賴準位，則電壓調 畴器300便開始運作，其中參考電壓訊號1由於需要提供給的 其他電路使用，所以參考電壓訊號I需要很快地到達125伏特， 另外’由上述重置電晶體Q2的導通條件可知，在時間Ή之前（亦 即電壓調希電路3〇〇啟動之前），重置控制電路3〇6將導通重置電 晶體Q2’而電容Css經由重置電晶體從放電直到軟啟動電壓訊號 # Vss的電壓準位是〇伏特，故當在時間τι時軟啟動電壓訊號％ 的初始電壓準位是〇伏特；此外，因為在時間Ή時啟動電壓調節 電路300 ’所以在時間T1時，回授電壓訊號^的電壓準位是〇 伏特’此時重置控制電路3〇6控制重置電晶體Q2不導通，電流源 iss開始對電容css充電’而軟啟動電壓訊號乂s的電壓準位便隨充 電時間而由0伏特逐漸遞增’於本創作之一實施例中，當軟啟動 電壓訊號vss等於參考賴訊號Vfef (卿前述的預定範圍為㈨ 時’誤差放大器OP2才會由軟啟動電壓訊號％切換至參考電壓 訊號Vref，所以，如第4圖所示’於時間Τ2時，軟啟動電壓訊號 M3 02193 vss等於參考電壓峨Vref，此時，輪出電㈣ 亦呈線性爬升到達2.5伏特，如前所=== 使用參考電壓替v 〇 <々差放大&OP2會選擇 便導通重置:二 上述條件㈡’重置控制電路 (亦即0伏特）。 置軟啟動電壓訊號Vss至接地準位M3 02193 VIII. New description: [New technical field] This creation provides a voltage regulating circuit, especially a voltage regulating circuit that avoids sudden drop of input voltage. [Prior Art] Generally, the voltage regulating circuit is connected in series between the input voltage signal and the output voltage signal, and functions like a voltage source for converting the input voltage signal into an output voltage signal and providing an output voltage signal. A stable voltage level. Please refer to Fig. 1, which is a circuit diagram of a conventional voltage regulator 10A. The voltage regulator 100 includes a transistor Q1, a feedback circuit 1〇2, an error amplifier OP1, and a uniformity circuit 110. The transistor Q1 can be an N-type field effect transistor (N-MOSFET) or a P-type field effect. A transistor (p_M〇SFET) or a dual-loaded junction transistor (BJT). In the first diagram, the transistor Qj is a p-type field effect transistor (P_MOSFET), and the source and the drain are respectively coupled to the input voltage signal Vin and the output voltage signal Vout, that is, the transistor Q1 is connected in series. Between the input voltage signal Vin and the output voltage signal v〇ut, in addition, the transistor ... is not in the feedback circuit 102, and the feedback circuit of the resistors Ri and R2 causes the feedback circuit to be generated once. The voltage signal is sent, and the feedback voltage signal is sent to the non-inverting input terminal of the error amplifier 0P1; in addition, for the error amplifier OP1, the non-inverting input terminal is secreted by the shouting voltage Wei Vfb, and the anti-her person is wealthy. Test voltage signal vref and another - start pin connection function circuit 11〇, wherein the enable circuit (10) 5 M3 02193 controls whether the control error amplifier OP1 starts to operate according to a start control signal εν, that is, controls the voltage regulation Whether the device 1 is enabled, for example, if the startup control signal EN is turned to a high logic level by a low logic level, 致, the enable circuit 110 will drive the error amplifier OP1 to start operating. The output of the error amplifier 〇p]l is coupled to the gate of the transistor Q1, thereby controlling the voltage signal to control the on-resistance of the transistor Q1; since the error amplifier OP1 functions as an error amplifier in the entire circuit, In other words, the control voltage signal will react back to the difference between the voltage signal and the reference voltage signal Vref to adjust the on-resistance of the transistor Qi, so that the output voltage signal v〇ut can be stabilized and the following is satisfied. Equation (1): — * ^ Equation (1) That is, the voltage regulator 100 achieves the purpose of stably generating the output voltage signal V〇ut-load 104 by the above equation. In addition, in the figure, Cin and c(10) represent the input capacitance and the output capacitance, respectively, for respectively stabilizing the input voltage signal Vin and the output voltage 峨vout. Since its operation and function are well known in the industry, no additional capital is provided. Said. σ月乡..., Fig. 2' Fig. 2 is a diagram showing the voltage regulation circuit 1A shown in Fig. 1. Assume that the input voltage signal Vin is 3.3 volts, the voltage is adjusted, that is, the reference voltage signal mu volt of the circuit 1〇0, and the required voltage signal vQUt is 2.5 volts, so, according to the above parameters The resistance of R2 is determined to form the desired feedback circuit (10). As shown in Figure 2, if the start control signal recording logic level is changed to the high logic level 6 M302193 bit at time T1, the voltage adjustment circuit will start to operate, which makes the reference voltage signal ^ need to be provided to other The line is used, so the reference voltage signal I needs to reach the preset value U5 volt very quickly. In addition, the output voltage of the output voltage signal v(10) is 0 volts at the time, so the feedback 峨% is also Q volt, and the result is an error amplifier. The output voltage of on is low voltage and the transistor is cut in the conduction region; at this time, the input voltage signal Vin (corresponding to a turn-in current signal D through the on-resistance of the transistor W charges the output capacitor c〇ut' due to the small on-resistance (generally about #毫一姆) The instantaneous current value of the input voltage machine Vin will be very large and reach the current limit Ilimit of the transistor Q1. Further, if the voltage regulation circuit is applied to a handheld product (such as a mobile phone, Digital camera, etc.), its input is usually secret to the battery '(4) The internal battery also has its internal resistance, therefore, this - instantaneous large current will cause the loss of η " Vln Voltage sag (v〇ltagedr〇p); in addition, if the sudden drop of the input voltage signal is too serious, it may also affect other systems connected to the battery to produce erroneous operation' and the axis to avoid this severe voltage drop phenomenon The input capacitance Cin of a larger capacitance value can be lightly connected to the wheel input end of the voltage adjustment circuit 100, but in order to use the input capacitance Cin having a larger capacitance value, the wire must be larger and more improved. Overall cost. This is an obvious new content for handheld products. One of the main purposes of this creation is to provide a voltage regulation circuit 1 that avoids input voltage dips and can have a smaller peach area. The problem mentioned above is less. M302193 According to the scope of the patent application of the present invention, a voltage regulating circuit is disclosed for generating an output voltage signal according to an input voltage signal. The voltage regulating circuit comprises a soft start circuit , for providing a soft start voltage signal; and a voltage approximator, consuming the soft start circuit, the input voltage signal and a reference voltage signal The method is configured to selectively compare the soft start voltage signal with one of the reference voltage signals and the output voltage signal corresponding to the output power signal to generate the output voltage signal according to the input voltage Φ signal. Please refer to FIG. 3, which is a circuit diagram of an embodiment of the present voltage regulating circuit 3A. As shown in FIG. 3, the voltage regulating circuit 3 includes a voltage regulator 302 and a soft A soft start circuit 304, wherein the voltage regulator 302 includes a transistor Q, a feedback circuit 303, a uniformity circuit 310, and an error amplification Is 0P2 'where the transistor Q1, the feedback circuit 303, and the enabler The structure and function of the circuit 310 are the same as those of the transistor qi, the feedback circuit 1〇2 and the enabling circuit 110 described in FIG. 1, and therefore will not be described here. Further, in FIG. 3, Cin and Cm respectively represent The input capacitor and the output capacitor are used to stabilize the input voltage signal Vin and the output voltage signal Vout respectively. Since its operation and function are well known in the industry, it will not be described here. The error amplifier OP2 is an error amplifier having three inputs. The non-inverting input is coupled to the feedback voltage signal Vfb, and the two inverting inputs are respectively coupled to the soft start voltage signal vss and the reference voltage signal vref. In this embodiment, after the voltage regulating circuit 300 is started, the error amplifier OP2 can selectively use M302193 to use the soft start voltage signal Vss or the reference voltage signal U. The operating principle of the voltage regulator 3〇2 is as shown in FIG. The operating principle of the voltage regulator 100 is similar. The difference is that the voltage regulator 302 can select one of the soft start voltage signal vss or the reference voltage signal vrefs to control the output voltage signal L and the input voltage signal Vin. Therefore, this embodiment is Defining a predetermined range, and when the voltage difference between the soft start voltage signal V% and the reference voltage tiger vref falls within the predetermined range (that is, whether the soft start voltage is less than or exceeds the reference voltage signal D, the predetermined range is usually one It is similar to the volts, that is, the soft-start voltage signal Vss is expected to be very close to the reference voltage vVref, the voltage regulating circuit 3 The switch from the soft start voltage signal Vss to the reference voltage signal vref to benefit the reference voltage signal Vref to control the output voltage to the output of the load 05 is vout. Please note that the predetermined range can be sighed according to the design requirements. For example, in one embodiment of the present invention, when the soft-start voltage signal VSS is equal to the reference voltage signal ^, the error amplifier is switched from the soft-start voltage signal vss to the reference voltage signal Vref. In addition, the error amplifier (10) _ 1 Select [small light work can be realized by using a multiplexer (mulle), however, any means of achieving selective light connection is the standard mouthpiece of the original error amplifier 0P2. The soft start circuit 3〇4 further includes a power flow U, a capacitor-reset transistor Q2, and a reset control circuit. According to one of the creations, the f source current Iss_ provides a reference current, (4) & is used as charge and discharge, so when the reset transistor is not turned on, the power supply will charge the capacitor L. Therefore, the voltage level of the soft-start voltage signal Vss will gradually be grounded (also That is, 0 volts) and increase. If the reset transistor Q2 is turned on, the power flow U cannot be charged to the capacitor Css and the capacitor & will begin to discharge via the reset transistor, so the soft start voltage is reduced by Vss. The electric freshener gradually reduces the Langqixia level. It is equal to the ground potential (that is, 0 volts). In addition, the reset control circuit 3〇6 is used to determine whether the reset transistor Q2 is turned on, in this embodiment, In order to break the soft-start voltage signal Vss corresponding to the ground potential every time the voltage regulating circuit 3 starts, the ON condition of the reset transistor Q2 is as follows: * · . (1) The start control signal EN is high logic The level shifts to a low logic level to turn off the operation of the error amplifier OP2; or (2) the error amplifier OP2 has been switched from the soft start voltage signal Vss to the reference voltage signal Vrcf. If the start control signal EN transitions from a high logic level to a low logic level before the error amplifier OP2 is switched from the soft start voltage signal Vss to the reference voltage signal Vref, and the operation of the error amplifier ΟΡ2 is turned off, the condition (1) ensures The soft start voltage signal Vss is reset before the next voltage adjustment circuit 300 is started; on the other hand, when the error amplifier OP2 has been switched from the soft start voltage signal Vss to the reference voltage signal Vref, the soft start voltage signal Vss is no longer It is used by the error amplifier OP2, so the reset control circuit 306 can allow the reset transistor Q2 to be turned on to reset the soft-start voltage signal Vss. In the preferred embodiment of the present invention, when the error amplifier OP2 is driven by the soft-start voltage signal When Vss is switched to the reference voltage signal Vref, the reset control circuit 306 immediately turns on the reset transistor Q2. However, the present invention is not limited thereto. In addition, when the startup control signal EN transitions from the low logic level to the high logic level, that is, when the voltage regulation circuit M302193 begins to start, the reset control circuit 3〇6 controls the reset transistor (3) to enter the non-conduction state. . HU# refers to the operation timing chart of the voltage adjustment circuit 300 shown in Fig. 4''4'. Assume that the input of the electric signal is in volts. In addition, the reference electric ship number U supplied to the voltage contact is 丨ΜVot and the required wheel voltage reading V〇ut is Μvolt, so it can be based on the above The parameters determine the resistance of the φ-out resistors R1, R2 to form the desired feedback circuit 3〇3. If the control register EN is switched from the low logic level to the high level in time, the voltage domain modulator 300 starts to operate, wherein the reference voltage signal 1 is used by other circuits that need to be supplied, so the reference voltage signal I It is necessary to reach 125 volts very quickly. In addition, it can be seen from the above-mentioned condition of resetting the transistor Q2 that the reset control circuit 3〇6 will be turned on before time ( (that is, before the voltage tuning circuit 3 is started). The transistor Q2' is placed and the capacitor Css is discharged from the reset transistor until the voltage level of the soft-start voltage signal #Vss is 〇V, so the initial voltage level of the soft-start voltage signal % is 〇V at time τ; In addition, since the voltage regulating circuit 300' is activated at time 所以, the voltage level of the feedback voltage signal ^ is 〇V at time T1. At this time, the reset control circuit 3〇6 controls the reset transistor Q2 to be non-conductive. The current source iss starts charging the capacitor css' and the voltage level of the soft-start voltage signal 乂s is gradually increased by 0 volts with the charging time. In one embodiment of this creation, when the soft-start voltage is Vss is equal to the reference signal Vfef (when the predetermined range is (9), the error amplifier OP2 will be switched from the soft start voltage signal % to the reference voltage signal Vref. Therefore, as shown in Fig. 4, the soft start is performed at time Τ2. The voltage signal M3 02193 vss is equal to the reference voltage 峨Vref. At this time, the wheel power-off (4) also climbs linearly to 2.5 volts. If the previous === use the reference voltage for v 〇<々 放大 amplification & OP2 will select to conduct Reset: 2 above condition (2) 'Reset control circuit (ie 0 volts). Set soft start voltage signal Vss to ground level
Ts〇ftsi tart sXKef ss 方程式(2) 電壓舉ΓΓ纖Q1GnF、電概触2ua以及參考 電壓喊Vref㈣醉㈣、為U5簡 毫秒:另外，由方程式(2)可知，當參二^ 盘電*丨’右想要魏短陳啟_間，電騎1ss的大小 ”電备Css的大小將是控制軟啟動時間τ_的因子亦即可 财較小的電邮^制較俩餘Css，可進—步降健 =ss所需侧的面積。請注意，電容Css可以是—固定電容值的 電各’並整合於電壓調節器姻的積體電路（晶片）内部；秋而， 電各Css亦可以獨立於電壓調節器的積體電路（晶片） 因制者可經㈣置適當電容值的電容來自由軟啟動時 間Tsoftstart ’其亦屬本創作之範嘴。以上軟啟動電壓峨V 線性方式逐漸上升，然而若軟㈣減Vss啡他遞增2 上升，亦屬本創作之範疇。 9 ^ M302193 此外，於上述實施例中，電壓調節器300所產生的輪出電壓 訊號Vout係為正電壓，然而，如熟習此項技藝者所知，依據上述 的技術揭露，可經由適當地改變第3圖所示之電壓調節器3〇〇的 架構即可使電壓調節器300用來產生負電壓的輸出電壓訊號 Vout。再者，於上述實施例中，電壓調節器3〇〇中的誤差放大器 OP2係於啟動控制訊號EN對應高邏輯準位時才啟動，然而，本 鲁創作並不以此為限。 相較於習知技術，誤差放大器OP2在電壓調節器3〇〇中的角 色係作為誤差放大器，回授電壓訊號Vft的電壓準位將跟隨軟啟動 電壓訊號Vss而變化，而電晶體Q1將緩慢導通，因此如第4圖所 示之輸入電壓訊號vin (對應輸入電流訊號Iin)的瞬間電壓變化值 將很小或趨近於0，因而將大大地減輕或去除輸入電壓訊號％的 鲁電壓突降，使得前述提到之電壓突降問題得以有效解決，而且， 本創作電壓調節電路300便不需如習知技術一般地在輪入電壓訊 號端設置較大電雜讀人f：SQn，齡之，她於f知電壓調 節電路’本創作電壓調節電路300的電路面積小，且成本低而更 加適用於手持式產品。 以上所述僅為本創作之較佳實施例，凡依本創作申請專利範 圍所做之均等變化與修飾，皆應屬本創作之涵蓋範圍。 M3 02193 【圖式簡單說明】 第1圖為根據習知電壓調郎電路的電路不意圖。 第2圖為第1圖所示之電壓調節電路的操作時序圖。 第3圖為本創作電壓調節電路之一實施例的電路示意圖。 第4圖為第3圖所示之電壓調節電路的操作時序圖。 【主要元件符號說明】 100、302 電壓調節器 102 、 303 回授電路 104、305 負載 110 、 310 致能電路 300 電壓調節電路 304 軟啟動電路 306 重置控制電路Ts〇ftsi tart sXKef ss Equation (2) Voltage ΓΓ Q Q1GnF, electric contact 2ua and reference voltage shout Vref (four) drunk (four), U5 simple milliseconds: In addition, from equation (2), when the two ^ ^ disk * 丨'Right wants Wei short Chen Kai _, the size of the electric ride 1ss" The size of the electric reserve Css will be the factor that controls the soft start time τ_, and the smaller the e-mail can be compared with the two Css. - step down = the area of the side required for ss. Please note that the capacitor Css can be - the fixed capacitance value of the electric each 'integrated in the integrated circuit of the voltage regulator (chip); autumn, the electricity Css also It can be independent of the voltage regulator's integrated circuit (wafer). Because the manufacturer can (4) set the appropriate capacitance value of the capacitor from the soft start time Tsoftstart 'which is also the scope of this creation. The above soft start voltage 峨V linear way gradually Rising, however, if soft (four) minus Vss and other increases, it is also within the scope of this creation. 9 ^ M302193 In addition, in the above embodiment, the voltage regulator Vout generated by the voltage regulator 300 is a positive voltage, however As known to those skilled in the art, based on the above It is disclosed that the voltage regulator 300 can be used to generate a negative voltage output voltage signal Vout by appropriately changing the architecture of the voltage regulator 3A shown in FIG. 3. Furthermore, in the above embodiment, the voltage The error amplifier OP2 in the regulator 3〇〇 is activated when the start control signal EN corresponds to a high logic level. However, Benlu's creation is not limited to this. Compared with the prior art, the error amplifier OP2 is in voltage regulation. The role of the device 3 is used as an error amplifier. The voltage level of the feedback voltage signal Vft will change with the soft-start voltage signal Vss, and the transistor Q1 will be turned on slowly, so the input voltage signal as shown in FIG. The instantaneous voltage change value of vin (corresponding to the input current signal Iin) will be small or close to zero, thus greatly reducing or eliminating the voltage voltage drop of the input voltage signal %, so that the aforementioned voltage dip problem is effective. Therefore, the present voltage regulating circuit 300 does not need to set a large electric miscellaneous reading person f:SQn at the wheeled voltage signal end as in the prior art, and she knows the voltage regulation at the age of The circuit of the present invention has a small circuit area and a low cost, and is more suitable for a handheld product. The above description is only a preferred embodiment of the present invention, and the equivalent variation of the patent application scope of the present invention is Modifications should be covered by this creation. M3 02193 [Simple description of the diagram] Figure 1 is a schematic diagram of the circuit according to the conventional voltage regulation circuit. Figure 2 is the operation of the voltage regulation circuit shown in Figure 1. Timing diagram. Fig. 3 is a circuit diagram of an embodiment of the voltage regulation circuit of the present invention. Fig. 4 is an operation timing diagram of the voltage regulation circuit shown in Fig. 3. [Description of main components] 100, 302 voltage regulator 102, 303 feedback circuit 104, 305 load 110, 310 enable circuit 300 voltage adjustment circuit 304 soft start circuit 306 reset control circuit