TWI716323B - Voltage generator - Google Patents

A voltage generator includes a bipolar transistor, configured to provide a base forward bias of negative temperature coefficient; a current generation circuit of positive temperature coefficient, configured to generate a positive reference temperature coefficient current and to multiply the positive reference temperature coefficient current by a magnification to generate a positive temperature coefficient current; a differential amplifier; an output-stage switching element, configured to provide an output voltage at an output node; and a first impedance unit and a second impedance unit, the first impedance unit is coupled to between the output node and a base of the bipolar transistor, and the second impedance unit is coupled to a control node, the base of the bipolar transistor and the positive temperature coefficient current.

電壓產生器 Voltage generator

本發明係指一種電壓產生器，尤指一種具有溫度補償及電流輸出能力的電壓產生器。 The present invention refers to a voltage generator, especially a voltage generator with temperature compensation and current output capabilities.

現有的電路設計領域中，電壓產生器(Voltage Generator或Voltage Regulator)用來產生輸出電壓，以對負載供電。一般而言，電壓產生器係根據一參考電壓以產生輸出電壓對負載供電，由於電路元件容易受到溫度影響，使得參考電壓也易受到溫度的影響，連帶造成電壓產生器無法提供穩定的輸出電壓。為了確保電壓產生器能夠作為穩定的電壓源，電壓產生器必須使用不受溫度影響的穩定參考電壓，現有技術以一能隙(band gap)參考電壓產生電路連接現有的電壓產生器，以產生經過溫度補償而相對不受溫度影響的參考電壓。然而，這會導致電壓產生器都必須額外配有能隙參考電壓產生電路，使得整體電路成本及體積因而增加。而且，能隙參考電壓產生電路所產生的參考電壓值不容易被調整，這會使得電壓產生器的應用彈性較低。因此，現有技術確實有改進的必要。 In the current circuit design field, a voltage generator (Voltage Generator or Voltage Regulator) is used to generate an output voltage to supply power to a load. Generally speaking, the voltage generator generates an output voltage based on a reference voltage to supply power to the load. Since circuit components are easily affected by temperature, the reference voltage is also easily affected by temperature, and the voltage generator cannot provide a stable output voltage. In order to ensure that the voltage generator can be used as a stable voltage source, the voltage generator must use a stable reference voltage that is not affected by temperature. The prior art uses a band gap reference voltage generating circuit to connect the existing voltage generator to generate a A reference voltage that is temperature compensated and relatively unaffected by temperature. However, this will cause the voltage generators to be additionally equipped with a band gap reference voltage generating circuit, which increases the overall circuit cost and volume. Moreover, the reference voltage value generated by the band gap reference voltage generating circuit is not easy to be adjusted, which makes the application flexibility of the voltage generator low. Therefore, there is indeed a need for improvement in the existing technology.

因此，本發明的主要目的即在於提供一種電壓產生器，其具有溫度 補償及電流輸出能力的電壓產生器，以解決上述問題。 Therefore, the main purpose of the present invention is to provide a voltage generator with a temperature Voltage generator with compensation and current output capability to solve the above problems.

本發明實施例揭露一種電壓產生器，包含有一雙極性接面型電晶體，具有一負溫度係數的基射極順向偏壓；一正溫度係數電流產生電路，耦接於該雙極性接面型電晶體的基極，該正溫度係數電流產生電路產生一參考正溫度係數電流，並且將該參考正溫度係數電流乘上一倍率而形成一正溫度係數電流；一誤差放大器，耦接於該雙極性接面型電晶體的集極；一輸出級開關元件，耦接於該誤差放大器及一輸出端，並於該輸出端提供一輸出電壓；以及一第一阻抗單元及一第二阻抗單元，該第一阻抗單元耦接於該輸出端與該雙極性接面型電晶體的基極之間，該第二阻抗單元耦接於該控制端、該雙極性接面型電晶體的基極及該正溫度係數電流。 The embodiment of the present invention discloses a voltage generator including a bipolar junction type transistor, a base emitter forward bias with a negative temperature coefficient; a positive temperature coefficient current generating circuit, coupled to the bipolar junction The base of the type transistor, the positive temperature coefficient current generating circuit generates a reference positive temperature coefficient current, and the reference positive temperature coefficient current is multiplied by a factor to form a positive temperature coefficient current; an error amplifier is coupled to the The collector of the bipolar junction transistor; an output stage switching element, coupled to the error amplifier and an output terminal, and provides an output voltage at the output terminal; and a first impedance unit and a second impedance unit , The first impedance unit is coupled between the output terminal and the base of the bipolar junction transistor, and the second impedance unit is coupled to the control terminal and the base of the bipolar junction transistor And the positive temperature coefficient current.

10:電壓產生器 10: Voltage generator

102:正溫度係數電流產生電路 102: Positive temperature coefficient current generating circuit

104:輸出級開關元件 104: output stage switching element

1022:電流鏡 1022: current mirror

1024:第一放大器 1024: first amplifier

A:誤差放大器 A: Error amplifier

I1:第一電流 I1: first current

I2:第二電流 I2: second current

I_B:基極電流 I _B : Base current

I_C:集極電流 I _C : Collector current

Iin:集極電流 Iin: Collector current

Iout:集極電流 Iout: Collector current

I_PTAT:參考正溫度係數電流 I _PTAT : reference positive temperature coefficient current

K*I_PTAT:正溫度係數電流 K*I _PTAT : positive temperature coefficient current

K、N:倍率 K, N: magnification

N1:控制端 N1: Control terminal

N2:輸出端 N2: output terminal

Q1:電晶體 Q1: Transistor

Q2:第二雙極性接面型電晶體 Q2: The second bipolar junction transistor

Q3:第三雙極性接面型電晶體 Q3: The third bipolar junction transistor

Vcc:輸入電壓 Vcc: input voltage

Vout:輸出電壓 Vout: output voltage

V_BE1:基射極順向偏壓 V _BE1 : Base emitter forward bias

Z₁:第一阻抗單元 Z ₁ : The first impedance unit

Z₂:第二阻抗單元 Z ₂ : The second impedance unit

Z₃:第三阻抗單元 Z ₃ : The third impedance unit

ΔV_BE:第三阻抗壓降 ΔV _BE : third impedance voltage drop

第1圖為本發明實施例之一電壓產生器之示意圖。 Figure 1 is a schematic diagram of a voltage generator according to an embodiment of the invention.

第2圖為本發明實施例之電壓產生器於應用時之一溫度與一輸入電壓之示意圖。 FIG. 2 is a schematic diagram of a temperature and an input voltage of the voltage generator according to an embodiment of the present invention in application.

第3圖為本發明實施例之電壓產生器於應用時，對應於不同輸入電壓的輸出電壓之示意圖。 FIG. 3 is a schematic diagram of output voltages corresponding to different input voltages when the voltage generator according to the embodiment of the present invention is applied.

請參考第1圖，第1圖為本發明實施例之一電壓產生器10之示意圖。電壓產生器10包含有一電晶體Q1、一正溫度係數電流K*I_PTAT、一誤差放大器A、一輸出級開關元件104、一第一阻抗單元Z₁及一第二阻抗單元Z₂。電壓產生器10 用來提供穩定的一輸出電壓Vout，以作為一積體電路(integrated circuit，IC)晶片內部元件的電壓源。 Please refer to Figure 1. Figure 1 is a schematic diagram of a voltage generator 10 according to an embodiment of the present invention. The voltage generator 10 includes a transistor Q1, a positive temperature coefficient current K*I _PTAT , an error amplifier A, an output stage switching element 104, a first impedance unit Z ₁ and a second impedance unit Z ₂ . The voltage generator 10 is used to provide a stable output voltage Vout as a voltage source for internal components of an integrated circuit (IC) chip.

在第1圖的實施例中，電壓產生器10可由一系統電源供電運作，該系統電源可包含一第一端及一第二端，該第一端及第二端之間的電壓即為一輸入電壓Vcc，在本實施例中，該第二端以一接地端表示，惟不以此為限。電晶體Q1為一雙極性接面型電晶體(bipolar junction transistor，BJT)，用來提供具有一負溫度係數的基射極順向偏壓V_BE1。正溫度係數電流K*I_PTAT是經由將一正溫度係數電流產生電路102產生的一參考正溫度係數電流I_PTAT乘上K倍所得，正溫度係數電流產生電路102產生之一端耦接於一控制端N1，控制端N1耦接於電晶體Q1的基極。誤差放大器A耦接於電晶體Q1的集極及輸出級開關元件104之間。輸出級開關元件104連接一輸出端N2，用來根據電晶體Q1之一集極電流I_C及誤差放大器A以在該輸出端N2提供輸出電壓Vout。第一阻抗單元Z₁耦接於該輸出端N2及該控制端N1之間，該第二阻抗單元Z2耦接於該控制端N1。 In the embodiment of Figure 1, the voltage generator 10 can be operated by a system power supply. The system power supply can include a first terminal and a second terminal. The voltage between the first terminal and the second terminal is a The input voltage Vcc, in this embodiment, the second terminal is represented by a ground terminal, but it is not limited thereto. Transistor Q1 is a bipolar junction transistor (BJT) used to provide a base-emitter forward bias voltage V _BE1 with a negative temperature coefficient. The positive temperature coefficient current K*I _PTAT is obtained by multiplying a reference positive temperature coefficient current I _PTAT generated by a positive temperature coefficient current generating circuit 102 by K times. One end of the positive temperature coefficient current generating circuit 102 is coupled to a control The terminal N1, the control terminal N1 is coupled to the base of the transistor Q1. The error amplifier A is coupled between the collector of the transistor Q1 and the output stage switching element 104. Output stage switch element 104 is connected an output terminal N2, according to one of the transistor Q1 and the collector current I _C A error amplifier to provide an output voltage Vout at the output terminal N2. First impedance means Z ₁ is coupled between the output terminal N2 and the control terminal N1, the second impedance unit Z2 is coupled to the control terminal N1.

在本實施例，上述電晶體Q1是一NPN型雙極性接面型電晶體，第一阻抗單元Z₁及第二阻抗單元Z₂分別可以是一電阻或其他阻抗元件，並且電晶體Q1不限於第1圖中的實施例的NPN型雙極性接面型電晶體，PNP型雙極性接面型電晶體也適用於本發明。 In this embodiment, the above-mentioned transistor Q1 is an NPN type bipolar junction transistor, the first impedance unit Z ₁ and the second impedance unit Z ₂ may be a resistor or other impedance elements, and the transistor Q1 is not limited to The NPN type bipolar junction type transistor of the embodiment in Figure 1 and the PNP type bipolar junction type transistor are also applicable to the present invention.

詳言之，在本實施例中，正溫度係數電流產生電路102包含一電流鏡1022，該電流鏡1022分別耦接一第二雙極性接面型電晶體Q2的集極及一第三雙極性接面型電晶體Q3的集極，以使第二、第三雙極性接面型電晶體Q2、Q3的集極電流Iout、Iin相同，其中第二雙極性接面型電晶體Q2之射極電流輸出作為一 參考正溫度係數電流I_PTAT；第三雙極性接面型電晶體Q3之射極則耦接一第三阻抗元件Z₃，第三阻抗元件Z₃也可以是一電阻或其他阻抗元件。第三雙極性接面型電晶體Q3之面積為第二雙極性接面型電晶體Q2之面積的N倍。一緩衝放大器1024(例如電壓隨耦器)耦接於第二、第三雙極性接面型電晶體Q2、Q3的基極與第二雙極性接面型電晶體Q2的集極之間，用來補償並確保第二、第三雙極性接面型電晶體Q2、Q3的集極電流Iout、Iin相同，惟該緩衝放大器1024亦可替換或省略，本發明並不以此為限。 In detail, in this embodiment, the positive temperature coefficient current generating circuit 102 includes a current mirror 1022 which is respectively coupled to the collector of a second bipolar junction transistor Q2 and a third bipolar The collector of the junction transistor Q3 so that the collector currents Iout and Iin of the second and third bipolar junction transistors Q2 and Q3 are the same, and the emitter of the second bipolar junction transistor Q2 The current output is used as a reference positive temperature coefficient current I _PTAT ; the emitter of the third bipolar junction transistor Q3 is coupled to a third impedance element Z ₃ , and the third impedance element Z ₃ can also be a resistor or other impedance element. The area of the third bipolar junction transistor Q3 is N times the area of the second bipolar junction transistor Q2. A buffer amplifier 1024 (such as a voltage follower) is coupled between the bases of the second and third bipolar junction transistors Q2 and Q3 and the collector of the second bipolar junction transistor Q2. To compensate and ensure that the collector currents Iout and Iin of the second and third bipolar junction transistors Q2 and Q3 are the same, but the buffer amplifier 1024 can be replaced or omitted, and the present invention is not limited to this.

通過電晶體Q1所提供的負溫度係數的基射極順向偏壓V_BE1，及正溫度係數電流產生電路102所產生的參考正溫度係數電流I_PTAT相互補償，使得本發明實施例的電壓產生器10可產生不易受溫度影響的輸出電壓Vout。 The base-emitter forward bias voltage V _BE1 with the negative temperature coefficient provided by the transistor Q1 and the reference positive temperature coefficient current I _PTAT generated by the positive temperature coefficient current generating circuit 102 compensate each other, so that the voltage generated in the embodiment of the present invention The device 10 can generate an output voltage Vout that is not easily affected by temperature.

值得注意的是，正溫度係數電流K*I_PTAT為參考正溫度係數電流I_PTAT的K倍，且K的值可以供設計以符合使用者需求，其中將該參考正溫度係數電流I_PTAT乘上K倍可以用電流鏡或各式電流轉換電路完成，恕不另行贅述。當誤差放大器A之極性為正時，輸出級開關元件104為一N型金氧半場效電晶體(NMOSFET)或一NPN型雙極性接面型電晶體；反之，當誤差放大器A之極性為負時，輸出級開關元件104為一P型金氧半場效電晶體(PMOSFET)或一PNP型雙極性接面型電晶體。此外，在本實施例中，第1圖中的第二雙極性接面型電晶體Q2及第三雙極性接面型電晶體Q3為NPN型雙極性接面型電晶體，但不限於此，PNP型雙極性接面型電晶體也適用於本發明。 It is worth noting that the positive temperature coefficient current K*I _PTAT is K times the reference positive temperature coefficient current I _PTAT , and the value of K can be designed to meet user needs, wherein the reference positive temperature coefficient current I _{PTAT is} multiplied by K times can be completed with a current mirror or various current conversion circuits, without further details. When the polarity of the error amplifier A is positive, the output stage switching element 104 is an N-type metal oxide half field effect transistor (NMOSFET) or an NPN type bipolar junction transistor; on the contrary, when the polarity of the error amplifier A is negative At this time, the output stage switching element 104 is a P-type metal oxide semi-field effect transistor (PMOSFET) or a PNP-type bipolar junction transistor. In addition, in this embodiment, the second bipolar junction transistor Q2 and the third bipolar junction transistor Q3 in Figure 1 are NPN bipolar junction transistors, but it is not limited to this, PNP type bipolar junction type transistors are also suitable for the present invention.

為便於詳細說明本發明實施例的電壓產生器10可產生不易受溫度影響的輸出電壓Vout，在本實施例中第一、第二及第三阻抗單元Z₁、Z₂、Z₃以電阻 舉例說明，且將第一、第二及第三阻抗單元Z₁、Z₂、Z₃的電阻值分別表示為Z₁、Z₂、Z₃。由第1圖可之，輸出電壓Vout為電晶體Q1的基射極順向偏壓V_BE1，再加上與流經第二阻抗單元Z₂之一第二電流I2和電阻值Z₂的乘積，即Vout=V_BE1+Z₂*I2...(1)。 In order to explain in detail that the voltage generator 10 of the embodiment of the present invention can generate an output voltage Vout that is not easily affected by temperature, in this embodiment, the first, second, and third impedance units Z ₁ , Z ₂ , Z ₃ are exemplified by resistors. Note, and the resistance values of the first, second, and third impedance units Z ₁ , Z ₂ , and Z ₃ are denoted as Z ₁ , Z ₂ , and Z _{3, respectively} . From Figure 1, the output voltage Vout is the base-emitter forward bias voltage V _{BE1 of the} transistor Q1, plus the product of the second current I2 flowing through the second impedance unit Z ₂ and the resistance value Z ₂ , That is, Vout=V _BE1 +Z ₂ *I2...(1).

其中，第二電流I2為流經第一阻抗單元Z₁之一第一電流I1、正溫度係數電流K*I_PTAT及電晶體Q1之一基極電流I_B之總和，即I2=I1+I_B+K*I_PTAT...(2)。 Wherein, the second current I2 is the sum of a first current I1, a positive temperature coefficient current K*I _PTA T and a base current I _B of the transistor Q1 flowing through the first impedance unit Z ₁ , that is, I2=I1+ I _B +K*I _PTAT ...(2).

因此，將式(2)帶入式(1)後，輸出電壓Vout可以被改寫為：Vout=V_BE1+Z₂*(I1+I_B+K*I_PTAT)...(3) Therefore, after putting equation (2) into equation (1), the output voltage Vout can be rewritten as: Vout=V _BE1 +Z ₂ *(I1+I _B +K*I _PTAT )...(3)

電晶體Q1之集極電流I_C=β*I_B，由於現有的雙極性接面型電晶體的放大參數β通常為50倍以上使得基極電流I_B較小，例如常見為奈安培(nA)數量級。因此，電晶體Q1的基極電流I_B因為數量級遠小於第一電流I1和正溫度係數電流K*I_PTAT的關係而可被忽略。另一方面，由於第一電流I1等於基射極順向偏壓V_BE1除以電阻值Z₁，而且參考正溫度係數電流I_PTAT等於第三阻抗單元Z₃之跨壓ΔV_BE除以電阻值Z₃。在此情形下，在忽略式(3)的基極電流I_B後可以被改寫為：

The collector current I _{C of the} transistor Q1 = β*I _B , since the amplification parameter β of the existing bipolar junction transistor is usually more than 50 times, the base current I _{B is} small, such as nanoamperes (nA )Magnitude. Therefore, the base current I _{B of the} transistor Q1 can be ignored because it is much smaller than the relationship between the first current I1 and the positive temperature coefficient current K*I _PTAT . On the other hand, since the first current I1 is equal to the base-emitter forward bias voltage V _BE1 divided by the resistance value Z ₁ , and the reference positive temperature coefficient current I _PTAT is equal to the cross voltage ΔV _BE of the third impedance unit Z ₃ divided by the resistance value Z ₃ . In this case, after ignoring the base current I _B of formula (3), it can be rewritten as:

其中，由於第二雙極性接面型電晶體Q2與第三雙極性接面型電晶體Q3的面積不一致，該第三雙極性接面型電晶體Q3之面積為該第二雙極性接面型電晶體Q2之面積的N倍。因此第三阻抗單元Z₃之跨壓ΔV_BE將會滿足下式，其中V_T為一熱電壓(thermal voltage)。 Wherein, since the area of the second bipolar junction transistor Q2 and the third bipolar junction transistor Q3 are different, the area of the third bipolar junction transistor Q3 is the second bipolar junction transistor N times the area of transistor Q2. Therefore, the cross voltage ΔV _{BE of the} third impedance unit Z ₃ will satisfy the following equation, where V _T is a thermal voltage.

ΔV_BE=ln(N)×V _T ...(5) ΔV _BE =ln( N )×V _T ... (5)

因此，合併上述式(4)和(5)，即可得到以下結果：

Therefore, combining the above equations (4) and (5), the following results can be obtained:

在式(6)當中，由於雙極性接面型電晶體的本身特性，基射極順向偏壓V_BE1具有負溫度係數，而熱電壓V_T具有正溫度係數，一般而言，兩者和溫度的關係可以表式如下，其中此處的K為溫度單位：

In equation (6), due to the characteristics of the bipolar junction transistor, the base-emitter forward bias voltage V _BE1 has a negative temperature coefficient, while the thermal voltage V _T has a positive temperature coefficient. Generally speaking, the two and The relationship of temperature can be expressed as follows, where K is the temperature unit:

如此一來，為了使得式(6)中的輸出電壓Vout不受溫度影響，因此進一步限定式(6)中的條件為：

In this way, in order to make the output voltage Vout in equation (6) not affected by temperature, the condition in equation (6) is further defined as:

也就是說，在滿足式(8)的情況下，輸出電壓Vout的溫度係數將接近零。如此一來，由式(6)可知，通過調整第一阻抗單元Z₁、第二阻抗單元Z₂及第三阻抗單元Z₃的電阻值Z₁、Z₂、Z₃、倍率K和倍率N，即可任意調整輸出電壓Vout，並且在滿足式(8)的條件下保持讓輸出電壓Vout為不易受溫度影響。 That is to say, in the case of satisfying equation (8), the temperature coefficient of the output voltage Vout will be close to zero. In this way, it can be seen from equation (6) that by adjusting the resistance values Z ₁ , Z ₂ , Z ₃ , magnification K and magnification N of the first impedance unit Z ₁ , the second impedance unit Z ₂ and the third impedance unit Z ₃ , The output voltage Vout can be adjusted arbitrarily, and the output voltage Vout can be kept insensitive to temperature under the condition of satisfying formula (8).

因此，本發明實施例的電壓產生器10通過貢獻正溫度係數電流K*I_PTAT以及關於負溫度係數的基射極順向偏壓的電晶體Q1相互補償，使得電壓 產生器10具有溫度補償的效果，以輸出不易受溫度影響的輸出電壓Vout。此外，電壓產生器10經由誤差放大器A和輸出級開關元件104在輸出端N2所產生的輸出電壓Vout具有電流輸出能力(sourcing capacity)，可作為IC晶片內部元件的電壓源。 Therefore, the voltage generator 10 of the embodiment of the present invention compensates each other by contributing the positive temperature coefficient current K*I _PTAT and the forward biased transistor Q1 with respect to the base emitter of the negative temperature coefficient, so that the voltage generator 10 has temperature compensation. The effect is to output the output voltage Vout that is not easily affected by temperature. In addition, the output voltage Vout generated by the voltage generator 10 at the output terminal N2 through the error amplifier A and the output stage switching element 104 has a current output capacity (sourcing capacity), which can be used as a voltage source for internal components of the IC chip.

以下舉一範例說明本發明實施例實際應用時應如何設計。若要設計一個在攝氏溫度27度下提供5伏特的輸出電壓Vout之電壓產生器10，假設在27度且電晶體Q1的偏壓電流(bias current)為1微安培(μA)時，基射極順向偏壓V_BE1為0.65伏，且β為50倍。首先，先決定讓輸出級的偏壓電流大於電晶體Q1的偏壓電流1μA，以進一步降低電晶體Q1的基極電流I_B的影響，因此設定第一電流I1=10μA，可得到Z₁=0.65V/10μA=65Kohm。 The following is an example to illustrate how the embodiment of the present invention should be designed in practical application. To design a voltage generator 10 that provides an output voltage Vout of 5 volts at 27 degrees Celsius, assuming that at 27 degrees and the bias current of transistor Q1 is 1 microampere (μA), the base emitter The extremely forward bias voltage V _BE1 is 0.65 volts, and β is 50 times. First, first decide to make the bias current of the output stage greater than the bias current of transistor Q1 by 1μA to further reduce the influence of the base current I _B of transistor Q1. Therefore, set the first current I1=10μA to obtain Z ₁ = 0.65V/10μA=65Kohm.

接著，該第三雙極性接面型電晶體Q3之面積需為該第二雙極性接面型電晶體Q2之面積的N倍，為了降低製程漂移，將第二雙極性接面型電晶體Q2、第三雙極性接面型電晶體Q3的設計較佳具有幾何對稱關係，在此例中，將N設定為8，可以讓第二、第三雙極性接面型電晶體Q2、Q3在電路布局時形成對稱結構。另外，將參考正溫度係數電流I_PTAT設定為2μA，可得到：

Then, the area of the third bipolar junction transistor Q3 needs to be N times the area of the second bipolar junction transistor Q2. In order to reduce the process drift, the second bipolar junction transistor Q2 , The design of the third bipolar junction transistor Q3 preferably has a geometric symmetry relationship. In this example, setting N to 8 can make the second and third bipolar junction transistors Q2 and Q3 in the circuit A symmetrical structure is formed during layout. In addition, setting the reference positive temperature coefficient current I _PTAT to 2μA, we can get:

最後，為了使得輸出電壓Vout不易受溫度影響，將電阻值Z₁、Z₃套用於前述式(8)，即可得到Z₂=224Kohm、K=5.17倍。如此一來，透過適當設計第一阻抗單元Z₁、第二阻抗單元Z₂及第三阻抗單元Z₃、倍率K和倍率N，即可任意調整輸出電壓Vout，進而得到出不受溫度影響的穩定的輸出電壓Vout。 Finally, in order to make the output voltage Vout less susceptible to temperature, the resistance values Z ₁ and Z _{3 are} applied to the aforementioned formula (8) to obtain Z ₂ =224Kohm and K=5.17 times. In this way, by appropriately designing the first impedance unit Z ₁ , the second impedance unit Z _2, and the third impedance unit Z ₃ , the magnification K and the magnification N, the output voltage Vout can be adjusted arbitrarily, and the output voltage Vout can be adjusted freely. Stable output voltage Vout.

當的電壓產生器具有負溫度係數時，則產生的曲線將應當隨著溫度升高而下降；相反地，當電壓產生器具有正溫度係數時，則產生的曲線應將隨著溫度升高而上升。關於本發明實施例的電壓產生器10的應用效果，請參考第2圖，第2圖為本發明實施例之電壓產生器10應用於一積體電路晶片之溫度與輸入電壓之示意圖。在第2圖中，X軸為應用環境之溫度(攝氏)、Y軸為輸出電壓(伏特)。當本發明實施例的電壓產生器10實際依據前述設計參數用來提供5V輸出電壓時，在不同的溫度(攝氏-40度至120度)下的輸出電壓大約都介於4.8伏特至5.08伏特之間，且輸出電壓沒有持續隨著溫度升高而不斷上升或下降，也就是說，本發明實施例的電壓產生器10確實具有對輸出電壓進行溫度補償的效果。 When the voltage generator has a negative temperature coefficient, the generated curve should decrease with increasing temperature; conversely, when the voltage generator has a positive temperature coefficient, the generated curve should decrease with increasing temperature rise. Regarding the application effect of the voltage generator 10 of the embodiment of the present invention, please refer to FIG. 2. FIG. 2 is a schematic diagram of the temperature and input voltage of the voltage generator 10 of the embodiment of the present invention applied to an integrated circuit chip. In Figure 2, the X-axis is the temperature of the application environment (Celsius), and the Y-axis is the output voltage (volts). When the voltage generator 10 of the embodiment of the present invention is actually used to provide a 5V output voltage according to the aforementioned design parameters, the output voltage at different temperatures (-40°C to 120°C) is approximately between 4.8V and 5.08V In addition, the output voltage does not continue to rise or fall as the temperature rises, that is, the voltage generator 10 of the embodiment of the present invention does have the effect of temperature compensation on the output voltage.

另一方面，第3圖為本發明實施例之電壓產生器10應用於積體電路晶片時，對應於不同輸入電壓的輸出電壓之示意圖。在第3圖的X軸為輸入電壓(伏特)、Y軸為輸出電壓(伏特)，第3圖中加入了在不同的製程漂移狀況下的電晶體模擬結果。其中，從第3圖中可以計算出，當電壓產生器10的輸入電壓改變時，輸出電壓的偏差僅為約70mV，電源供應抑制比例(Power Supply Rejection Ratio，PSRR)可達約80dB。而且不論是FF(快NMOS及快PMOS)、FS(快NMOS及慢PMOS)、TT(典型NMOS及典型PMOS)、SF(慢NMOS及快PMOS)還是SS(慢NMOS及慢PMOS)的模擬結果均相當優異。也就是說，本發明實施例的電壓產生器10確實可作為一低壓差穩壓器(Low-dropout regulator，LDO)元件來供電給晶片內部元件，同時又兼具溫度補償功能，故可在不同溫度條件下提供穩定的輸出電壓。 On the other hand, FIG. 3 is a schematic diagram of output voltages corresponding to different input voltages when the voltage generator 10 according to an embodiment of the present invention is applied to an integrated circuit chip. In Figure 3, the X-axis is the input voltage (Volt) and the Y-axis is the output voltage (Volt). Figure 3 adds the simulation results of the transistor under different process drift conditions. Among them, it can be calculated from Figure 3 that when the input voltage of the voltage generator 10 changes, the deviation of the output voltage is only about 70 mV, and the Power Supply Rejection Ratio (PSRR) can reach about 80 dB. And whether it is FF (fast NMOS and fast PMOS), FS (fast NMOS and slow PMOS), TT (typical NMOS and typical PMOS), SF (slow NMOS and fast PMOS) or SS (slow NMOS and slow PMOS) simulation results Both are quite excellent. In other words, the voltage generator 10 of the embodiment of the present invention can indeed be used as a low-dropout regulator (LDO) component to supply power to the internal components of the chip, and it also has a temperature compensation function. Provide stable output voltage under temperature conditions.

綜上所述，本發明實施例提供一種電壓產生器，通過正溫度係數電 流及負溫度係數的偏壓以相互補償，以提供溫度補償且輸出不易受溫度影響的輸出電壓。並且，本發明實施例的電壓產生器具有電流輸出能力，以作為IC晶片內部元件的穩定電壓源，而不需要額外設置能隙參考電壓產生電路，進而有效降低整體電路成本及體積。 In summary, the embodiment of the present invention provides a voltage generator, which uses positive temperature coefficient The bias voltage of current and negative temperature coefficient can compensate each other to provide temperature compensation and output an output voltage that is not easily affected by temperature. In addition, the voltage generator of the embodiment of the present invention has a current output capability to serve as a stable voltage source for the internal components of the IC chip, without an additional band gap reference voltage generating circuit, thereby effectively reducing the overall circuit cost and volume.

以上所述僅為本發明之較佳實施例，凡依本發明申請專利範圍所做之均等變化與修飾，皆應屬本發明之涵蓋範圍。 The foregoing descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made in accordance with the scope of the patent application of the present invention shall fall within the scope of the present invention.

10:電壓產生器 10: Voltage generator

102:正溫度係數電流產生電路 102: Positive temperature coefficient current generating circuit

104:輸出級開關元件 104: output stage switching element

1022:電流鏡 1022: current mirror

1024:第一放大器 1024: first amplifier

A:誤差放大器 A: Error amplifier

I1:第一電流 I1: first current

I2:第二電流 I2: second current

I_B:基極電流 I _B : Base current

I_C:集極電流 I _C : Collector current

Iin:集極電流 Iin: Collector current

Iout:集極電流 Iout: Collector current

I_PTAT:參考正溫度係數電流 I _PTAT : reference positive temperature coefficient current

K*I_PTAT:正溫度係數電流 K*I _PTAT : positive temperature coefficient current

K、N:倍率 K, N: magnification

N1:控制端 N1: Control terminal

N2:輸出端 N2: output terminal

Q1:電晶體 Q1: Transistor

Q2:第二雙極性接面型電晶體 Q2: The second bipolar junction transistor

Q3:第三雙極性接面型電晶體 Q3: The third bipolar junction transistor

Vcc:輸入電壓 Vcc: input voltage

Vout:輸出電壓 Vout: output voltage

V_BE1:基射極順向偏壓 V _BE1 : Base emitter forward bias

Z₁:第一阻抗單元 Z ₁ : The first impedance unit

Z₂:第二阻抗單元 Z ₂ : The second impedance unit

Z₃:第三阻抗單元 Z ₃ : The third impedance unit

ΔV_BE:第三阻抗壓降 ΔV _BE : third impedance voltage drop

一種電壓產生器，包含有：一雙極性接面型電晶體，具有一負溫度係數的基射極順向偏壓；一正溫度係數電流產生電路，耦接於該雙極性接面型電晶體的基極，該正溫度係數電流產生電路產生一參考正溫度係數電流，並且將該參考正溫度係數電流乘上一倍率而形成一正溫度係數電流；一誤差放大器，耦接於該雙極性接面型電晶體的集極；一輸出級開關元件，耦接於該誤差放大器及一輸出端，並於該輸出端提供一輸出電壓；以及一第一阻抗單元及一第二阻抗單元，該第一阻抗單元耦接於該輸出端與該雙極性接面型電晶體的基極之間，該第二阻抗單元耦接於該控制端、該雙極性接面型電晶體的基極及該正溫度係數電流。 A voltage generator comprising: a bipolar junction type transistor with a base emitter forward bias with a negative temperature coefficient; a positive temperature coefficient current generating circuit coupled to the bipolar junction type transistor The positive temperature coefficient current generating circuit generates a reference positive temperature coefficient current, and the reference positive temperature coefficient current is multiplied by a factor to form a positive temperature coefficient current; an error amplifier is coupled to the bipolar connection The collector of the area transistor; an output stage switching element, coupled to the error amplifier and an output terminal, and provides an output voltage at the output terminal; and a first impedance unit and a second impedance unit, the first An impedance unit is coupled between the output terminal and the base of the bipolar junction transistor, and the second impedance unit is coupled to the control terminal, the base of the bipolar junction transistor and the positive Temperature coefficient current. 如請求項1所述之電壓產生器，其中流經該第二阻抗單元之一第二電流為流經該第一阻抗單元之一第一電流、該正溫度係數電流及該雙極性接面型電晶體之一基極電流之總和。 The voltage generator according to claim 1, wherein a second current flowing through the second impedance unit is a first current flowing through the first impedance unit, the positive temperature coefficient current, and the bipolar junction type The sum of the base current of one of the transistors. 如請求項1所述之電壓產生器，其中該正溫度係數電流產生電路包含有：一電流鏡；一第二雙極性接面型電晶體，該第二雙極性接面型電晶體的集極耦接該電流鏡之一端；以極一第三雙極性接面型電晶體，該第三雙極性接面型電晶體的集極耦接該電流鏡之另一端； 其中，該第二雙極性接面型電晶體之射極電流輸出作為該參考正溫度係數電流，該第三雙極性接面型電晶體之射極耦接一第三阻抗元件，該第三雙極性接面型電晶體之面積為該第二雙極性接面型電晶體之面積的N倍。 The voltage generator according to claim 1, wherein the positive temperature coefficient current generating circuit includes: a current mirror; a second bipolar junction transistor, the collector of the second bipolar junction transistor One end of the current mirror is coupled; a third bipolar junction transistor is poled, and the collector of the third bipolar junction transistor is coupled to the other end of the current mirror; Wherein, the emitter current output of the second bipolar junction transistor is used as the reference positive temperature coefficient current, the emitter of the third bipolar junction transistor is coupled to a third impedance element, and the third double The area of the polar junction transistor is N times the area of the second bipolar junction transistor. 如請求項3所述之電壓產生器，其中該正溫度係數電流為該參考正溫度係數電流的K倍，該第一阻抗單元、該第二阻抗單元及該第三阻抗單元分別具有電阻值Z₁、Z₂、Z₃，且滿足以下條件：

其中，V_BE1為該雙極性接面型電晶體的基射極順向偏壓，V_T為該第三雙極性接面型電晶體的熱電壓。 The voltage generator according to claim 3, wherein the positive temperature coefficient current is K times the reference positive temperature coefficient current, and the first impedance unit, the second impedance unit, and the third impedance unit each have a resistance value Z ₁ , Z ₂ , Z ₃ , and meet the following conditions:

Wherein, V _{BE1 is} the forward bias voltage of the base emitter of the bipolar junction transistor, and V _{T is} the thermal voltage of the third bipolar junction transistor. 如請求項3所述之電壓產生器，其中該正溫度係數電流產生電路另包含一緩衝放大器耦接於該第二雙極性接面型電晶體的基極與集極之間。 The voltage generator according to claim 3, wherein the positive temperature coefficient current generating circuit further includes a buffer amplifier coupled between the base and the collector of the second bipolar junction transistor. 如請求項3所述之電壓產生器，其中第二雙極性接面型電晶體和該第三雙極性接面型電晶體的集極電流相同。 The voltage generator according to claim 3, wherein the collector current of the second bipolar junction transistor and the third bipolar junction transistor are the same. 如請求項2所述之電壓產生器，其中該雙極性接面型電晶體操作於一偏壓電流下，且該第一電流大於該偏壓電流。 The voltage generator according to claim 2, wherein the bipolar junction transistor operates under a bias current, and the first current is greater than the bias current. 如請求項1所述之電壓產生器，其中當該誤差放大器之一極性為正時，該輸出級開關元件為一N型金氧半場效電晶體(NMOSFET)或一NPN型雙極性接面型電晶體；當該誤差放大器之該極性為負時，該輸出級開關元 件為P型金氧半場效電晶體(PMOSFET)或一PNP型雙極性接面型電晶體。 The voltage generator according to claim 1, wherein when one of the polarity of the error amplifier is positive, the output stage switching element is an N-type metal oxide semi-field effect transistor (NMOSFET) or an NPN-type bipolar junction type Transistor; when the polarity of the error amplifier is negative, the output stage switching element The device is a P-type metal oxide half-field effect transistor (PMOSFET) or a PNP-type bipolar junction transistor.