TWI325672B - Linear battery charger - Google Patents

Description

1325672 九、發明說明： 【發明所屬之技術領域】 本案係有關於種線性充電器（linear battery charger)。 . 【先前技4标】 • 線性充電器的操作通常包括一定電流充電模式 (constant current charge mode)以及一定電壓充電模式 • (constant voltage charge mode)。在充電一電池模組時，線 性充電電路首先會以該定電流充電模式充電該電池模組， 直到該電池模組之電位(Vbat)達到某一準位後，才改以該定 電壓充電模式充電該電池模組。以4.2伏特的鋰電池為例， 線性充電器首先以該定電流充電模式充電該鋰電池。待該 鋰電池充電至4.1伏特，該線性充電電路會切換至該定電 壓充電模式繼續將該鐘電池之電位(Vbat)充電至4 2伏特。 該定電壓充電模式乃用來避免過度充電該鐘電池，以延長 籲該裡電池的使用壽命。 第1圖為一傳統線性充電器100。該傳統線性充電器 100具有一充電電晶體gmp，用以充電一電池模組1〇2。該 J 傳統線性充電器100的運作如下。在一定電流充電模式 • 下，一第一開關SW1導通並且一第二開關sw2不導通。一 第一運算放大器OPi、一第二運算放大器0p2、一電晶體 gmnc、與該充電電日日體gmp所形成的迴路會令流經一感測電 阻Rsns的一電流I維持在固定值，其大小由耦接該第二運 算放大器〇P2的一第一參考電位vrefl決定。電容Cc與電1325672 IX. Description of the invention: [Technical field to which the invention pertains] This case relates to a linear battery charger. [Prior 4] The operation of a linear charger usually includes a constant current charge mode and a constant voltage charge mode. When charging a battery module, the linear charging circuit first charges the battery module in the constant current charging mode until the potential of the battery module (Vbat) reaches a certain level, and then changes to the constant voltage charging mode. Charge the battery module. Taking a 4.2 volt lithium battery as an example, the linear charger first charges the lithium battery in the constant current charging mode. When the lithium battery is charged to 4.1 volts, the linear charging circuit switches to the constant voltage charging mode to continue charging the battery potential (Vbat) to 42 volts. The constant voltage charging mode is used to avoid overcharging the battery to prolong the life of the battery. Figure 1 shows a conventional linear charger 100. The conventional linear charger 100 has a charging transistor gmp for charging a battery module 1〇2. The J conventional linear charger 100 operates as follows. In a certain current charging mode, a first switch SW1 is turned on and a second switch sw2 is not turned on. A first operational amplifier OPi, a second operational amplifier 0p2, a transistor gmnc, and a circuit formed by the charging electric solar cell gmp maintain a current I flowing through a sensing resistor Rsns at a fixed value. The size is determined by a first reference potential vref1 coupled to the second operational amplifier 〇P2. Capacitor Cc and electricity

Client’s Docket N〇“VIT06-0146 TT*s Docket N〇;0608-A41004-TW/FinaI /Glorious Tien 6 1325672 阻以且成該線性充電器議在該定電流充電模式 的一頻率補償電路。在—定電壓充電模式下， Γ、不-導電通二且一第二開關SW2導通。-第“算放:器 體gmnv、與該充電電晶體8叫所形成的迴路會 7該電池模組之電位v b at維持在一第二參考電位V 。 容Cz與電阻Rz組成該線性充電器1〇〇在該定 # 式下所需要的一頻率補償電路。 吳Client's Docket N〇"VIT06-0146 TT*s Docket N〇;0608-A41004-TW/FinaI /Glorious Tien 6 1325672 is a frequency compensation circuit that is blocked by the linear charger in the constant current charging mode. In the constant voltage charging mode, Γ, --conducting two and one second switch SW2 are turned on. - The first "calculation: the body gmnv, and the circuit formed by the charging transistor 8 will 7 the potential of the battery module Vb at is maintained at a second reference potential V. The capacitor Cz and the resistor Rz constitute a frequency compensation circuit required by the linear charger 1 in the fixed mode. Wu

為了確保該傳統線性充電器100在該定 與該定電壓充電模式下能夠正確操作，傳统線性電^ 1〇〇所採用的運算放大器0Pl、0P2、與OP3 ::: 確運算放大1 °因此，傳統線性 充電器100的成本相當高。 β此外’傳統線性充電器100的頻率補償電路非常大（尤 其是電容cz與電阻Rz)，將在該傳統線性充電器1〇〇上佔 據較大的面積。 【發明内容】 本發明提供一種新穎的線性充電器（linear battery charger)’不僅大幅減少精確運算放大器的使用量，更大幅 降低其頻率補償電路所佔據的面積。 本發明所提供的線性充電器包括一第一電流產生器、 一電流偵測器、一第一運算放大器、以及一多工選擇裝置。 該第一電流產生器產生一第一電流，並且耦接一電池模組 以充電該電池模組。該電流偵測器耦接該第一電流產生 器，用以產生與該第一電流對應的一感測電位。該第一運In order to ensure that the conventional linear charger 100 can operate correctly in the constant voltage charging mode, the operational amplifiers 0P1, 0P2, and OP3 ::: used in the conventional linear circuit are amplified by 1 °, The cost of the conventional linear charger 100 is quite high. In addition, the frequency compensation circuit of the conventional linear charger 100 is very large (especially the capacitor cz and the resistor Rz), and will occupy a large area on the conventional linear charger. SUMMARY OF THE INVENTION The present invention provides a novel linear battery charger that not only greatly reduces the amount of precision operational amplifier used, but also substantially reduces the area occupied by its frequency compensation circuit. The linear charger provided by the present invention includes a first current generator, a current detector, a first operational amplifier, and a multiplex selection device. The first current generator generates a first current and is coupled to a battery module to charge the battery module. The current detector is coupled to the first current generator for generating a sensing potential corresponding to the first current. The first luck

Client’s Docket No.:VIT06-0146 TT’s Docket No:0608-A41004-TW/Final /GloriousJTien Ί 1325672 • 算放大器具有一第一輸入端、一第二輸入端以及一輸出 端。該第一運算放大器之輸出端耦接該第一電流產生器之 一控制端。在一定電流充電模式下，該多工選擇裝置會將 一第一參考電位以及該感測電位分別耦接至該第一運算放 大器之第一及第二輸入端。該第一運算放大器可藉此維持 該第一電流為一定值電流。在一定電壓充電模式下，該多 工選擇裝置會將一第二參考電位以及該電池模組之電位分 別耦接至該第一運算放大器之第一及第二輸入端。該第一 • 運算放大器可藉此調整該電池模組之電位至一定值電位。 為讓本發明之上述和其他目的、特徵、和優點能更明 • 顯易懂，下文特舉出較佳實施例，並配合所附圖式作詳細 說明。 【實施方式】 第2圖為本發明的一實施例。一線性充電器200包括 一第一電流產生器202、一電流偵測器204、一第一運算放 • 大器OPi、以及一多工選擇裝置206。該第一電流產生器 202耦接一電池模組208以充電該電池模組208。該第一電 流產生裔所產生的電流為·一第一電流Ιι。該電流4貞測204 ' 耦接該第一電流產生器202，並且對應該第一電流I!的大 • 小輸出一感測電位Vsns。該第一運算放大器OPi，具一第 一輸入端（如圖所示之非反相輸入端）、一第二輸入端（如圖 所示之反相輸入端）、以及一輸出端。該第一運算放大器 ΟΡι之輸出端耦接該第一電流產生器202之控制端，以控 制該第一電流Ιι的大小。在一定電流充電模式下，該多工Client's Docket No.: VIT06-0146 TT’s Docket No: 0608-A41004-TW/Final /GloriousJTien Ί 1325672 • The amplifier has a first input, a second input, and an output. The output of the first operational amplifier is coupled to a control terminal of the first current generator. In a certain current charging mode, the multiplex selection device couples a first reference potential and the sensing potential to the first and second inputs of the first operational amplifier, respectively. The first operational amplifier can thereby maintain the first current as a constant current. In a certain voltage charging mode, the multiplex device couples a second reference potential and a potential of the battery module to the first and second inputs of the first operational amplifier, respectively. The first operational amplifier can thereby adjust the potential of the battery module to a certain potential. The above and other objects, features, and advantages of the present invention will become more apparent from Embodiments Fig. 2 is an embodiment of the present invention. A linear charger 200 includes a first current generator 202, a current detector 204, a first operational amplifier OPi, and a multiplex selection device 206. The first current generator 202 is coupled to a battery module 208 to charge the battery module 208. The current generated by the first current generation is a first current Ιι. The current 4 sense 204' is coupled to the first current generator 202 and corresponds to a large output of the first current I! to a sense potential Vsns. The first operational amplifier OPi has a first input terminal (as shown in the non-inverting input terminal), a second input terminal (inverted input terminal as shown), and an output terminal. The output end of the first operational amplifier ΟΡ1 is coupled to the control end of the first current generator 202 to control the magnitude of the first current Ιι. In a certain current charging mode, the multiplex

Clients Docket No.:VIT06-0146 TT’s Docket No:0608-A41004-TW/Final /GloriousTien ^ 1325672 - 選擇裝置206將一第一參考電位Vrefl以及該感測電位Vsns 分別耦接至該第一運算放大器OPii第一及第二輸入端。 在一定電壓充電模式下，該多工選擇裝置206將一第二參 考電位Vref2W及該電池模組之電位Vbat分別耦接至該第一 運算放大器OPii第一及第二輸入端。 在第2圖所示之實施例中，該第一電流產生器202為 一第一金氧半電晶體、其汲極耦接該電池模組208，並 且其閘極耦接該第一運算放大器OP!之輸出端作為該第一 • 電流產生器202之控制端。此外，該電流偵測器204包括 一第二金氧半電晶體M2與一感測電阻Rsns。該第二金氧半 電晶體M2之閘極與該第一金氧半電晶體Mi之閘極耦接在 一起，並且該第一與第二金氧半電晶體Mi與M2具有相同 的閘源極壓降。因此，該第二金氧半電晶體M2所產生的 一第二電流12可與該第一電流Ii成一比例關係，其大小乃 由該第一與該第二金氧半電晶體Μι與M2的面積比例決 定。該感測電阻Rsns耦接於第二金氧半電晶體M2之汲極， * 用以將該第二電流12轉換成該感測電位Vsns。在另一實施 例中，該感測電阻Rsns可為可變電阻，用以確保該第二金 . 氧半電晶體M2可操作在飽和區。 參閱第2圖，該多工選擇裝置206可由兩個多工器mux! 與mux2組成。在該定電流充電模式下，該多工器muxi將 該第一參考電位Vrefl輸入該第一運算放大器OPii反相輸 入端，並且該多工器mux2將該感測電位Vsns輸入該第一運 算放大器OPii非反相輸入端。該第一電流Ii變大時，該Clients Docket No.: VIT06-0146 TT's Docket No: 0608-A41004-TW/Final /GloriousTien ^ 1325672 - The selection device 206 couples a first reference potential Vref1 and the sensing potential Vsns to the first operational amplifier OPii First and second inputs. In a certain voltage charging mode, the multiplex selection device 206 couples a second reference potential Vref2W and a potential Vbat of the battery module to the first and second input terminals of the first operational amplifier OPii. In the embodiment shown in FIG. 2, the first current generator 202 is a first MOS transistor, the drain is coupled to the battery module 208, and the gate is coupled to the first operational amplifier. The output of OP! serves as the control terminal of the first current generator 202. In addition, the current detector 204 includes a second MOS transistor M2 and a sense resistor Rsns. The gate of the second MOS transistor M2 is coupled to the gate of the first MOS transistor Mi, and the first and second MOS transistors Mi and M2 have the same gate source Extreme pressure drop. Therefore, a second current 12 generated by the second MOS transistor M2 can be proportional to the first current Ii, and the size is determined by the first and second MOS transistors Μ and M2. The area ratio is determined. The sensing resistor Rsns is coupled to the drain of the second MOS transistor M2, and is configured to convert the second current 12 into the sensing potential Vsns. In another embodiment, the sense resistor Rsns can be a variable resistor to ensure that the second gold oxygen transistor M2 is operable in the saturation region. Referring to Figure 2, the multiplex selection device 206 can be comprised of two multiplexers mux! and mux2. In the constant current charging mode, the multiplexer muxi inputs the first reference potential Vref1 to the inverting input terminal of the first operational amplifier OPii, and the multiplexer mux2 inputs the sensing potential Vsns into the first operational amplifier OPii non-inverting input. When the first current Ii becomes large, the

Client's Docket N〇.:VIT06-0146 TT's Docket No:0608-A41004-TW/Final /Glorious_Tien 1325672 第二電流I2會隨之變大，導致該感測電位vsns上升。該第 一運算放大器0P〗比較該感測電位vsns與該第一參考電位 vrefl後，其輸出端信號會提升該第一金氧半電晶體之 閘極電壓Vg，導致該第一金氧半電晶體之閘源極壓差 變小，該第一電流Ιι被往下調整回原來的準位。在該定電 壓充電模式下，該多工器muxi將該第二參考電位Vref2輪 入該第一運算放大器OPi之反相輸入端，並且該多工器 mux2將該電池模組之電位Vbat輸入該第一運算放大器〇Pl 之非反相輸入端。該電池模組之電位Vbat尚未達到該第二 參考電位Vref2時，該第一運算放大器〇?1會調降該第一金 氧半電晶體Μ!之閘極電壓Vg，導致該第一電流“變大， 以充電該電池模組208至該第二參考電位Vref2。 由第2圖所示之實施例可發現，本發明僅僅需要一個 低偏移電壓（low offset)的精確運算放大器（第一運算放大 器〇Pi)。與傳統線性充電器相比，本發明大幅減少精確運 算放大器的使用量。 本發明的另一項優點是降低晶片的針腳數目。以第2 圖之線性充電器200為例，僅有感測電阻Rsns外接在晶片 外’其餘元件都整合在晶片内部。該線性充電器2〇〇的晶 片部分僅需要三個針腳分別連接一電源端VDD、該電池模 組208、以及該感測電阻Rsns。反觀第1圖之傳統線性充電 器100 ’該測電阻Rsns、該充電電晶體gmp、電容Cz、以及 電阻Rz皆為外接元件。故傳統線性充電器1〇〇的晶片部分 至少需要四個針腳104、106、108、以及11〇。Client's Docket N〇.:VIT06-0146 TT's Docket No:0608-A41004-TW/Final /Glorious_Tien 1325672 The second current I2 will become larger, causing the sense potential vsns to rise. After the first operational amplifier OP compares the sensing potential vss and the first reference potential vref1, the output signal thereof increases the gate voltage Vg of the first MOS transistor, resulting in the first MOS and a half. The gate-source voltage difference of the crystal becomes smaller, and the first current Ι is adjusted downward to the original level. In the constant voltage charging mode, the multiplexer muxi turns the second reference potential Vref2 into the inverting input end of the first operational amplifier OPi, and the multiplexer mux2 inputs the potential Vbat of the battery module into the The non-inverting input of the first operational amplifier 〇P1. When the potential Vbat of the battery module has not reached the second reference potential Vref2, the first operational amplifier 〇?1 will lower the gate voltage Vg of the first MOS transistor, resulting in the first current. Increasing to charge the battery module 208 to the second reference potential Vref2. As can be seen from the embodiment shown in FIG. 2, the present invention requires only a low offset precision operational amplifier (first The operational amplifier 〇Pi). Compared with the conventional linear charger, the present invention greatly reduces the amount of precision operational amplifier used. Another advantage of the present invention is to reduce the number of pins of the wafer. Take the linear charger 200 of FIG. 2 as an example. Only the sense resistor Rsns is externally connected to the chip. The remaining components are integrated inside the chip. The chip portion of the linear charger 2 requires only three pins to be respectively connected to a power terminal VDD, the battery module 208, and the like. The sensing resistor Rsns. In contrast, the conventional linear charger 100 of Fig. 1 'the measuring resistor Rsns, the charging transistor gmp, the capacitor Cz, and the resistor Rz are external components. Therefore, the conventional linear charger 1〇〇 Sheet portion requires at least four pins 104, 106, and 11〇.

Client's Docket N〇.:V1T06-0146 TT*s Docket N〇;0608-A41004-TW/Final /Glorious Tien 1325672 第3圖為本發明的另一實施例。線性充電器300較第 2圖之線性充電器200多了 一電壓準位控制電路302。該電 壓準位控制電路302耦接於該第二金氧半電晶體M2之汲 極與該感測電阻Rsns之間，其中包括一第三金氧半電晶體 M3以及一第二運算放大器OP2。該第三金氧半電晶體M3 之源極與汲極分別耦接該第二金氧半電晶體M2之汲極與 ' 該感測電阻Rsns。該第三金氧半電晶體M3之閘極由該第二 運算放大器OP2之輸出端控制。在此實施例中，該第二運 • 算放大器OP2之非反相以及反相輸入端分別耦接該第一金 氧半電晶體Μ!之汲極以及該第二電金氧半電晶體M2之汲 極。該電壓準位控制電路302的作用為令該第一與該第二 金氧半電晶體Μι與M2具有同樣的汲極電壓（其值為 Vbat)，以確保該第一與該第二金氧半電晶體皿1與M2所產 生的第一與第二電流h與12成固定比例。 第4圖為本發明的另一實施例。線性充電器400較第 3圖之線性充電器300多了一頻率補償電路402。如第4 ® 圖之實施例，該頻率補償電路402包括複數個電阻(I與 R2)、一分壓點404、一頻率補償器406、以及一可變電容 C。該等電阻I與R2與該分壓點404串接於該電池模組 408以及一接地端之間。該電池模組之電位Vbaj^該等電 阻1^與R2分壓後由該分壓點404輸出至該多工選擇裝置 410。該頻率補償器406耦接於該電池模組408與該分壓點 404之間。該可變電容C耦接於該頻率補償器406與該接 地端之間。在該定電壓充電模式下，該頻率補償電路402Client's Docket N〇.: V1T06-0146 TT*s Docket N〇; 0608-A41004-TW/Final/Glorious Tien 1325672 FIG. 3 is another embodiment of the present invention. The linear charger 300 has a voltage level control circuit 302 more than the linear charger 200 of FIG. The voltage level control circuit 302 is coupled between the anode of the second MOS transistor M2 and the sense resistor Rsns, and includes a third MOS transistor M3 and a second operational amplifier OP2. The source and the drain of the third MOS transistor M3 are respectively coupled to the drain of the second MOS transistor M2 and the sensing resistor Rsns. The gate of the third MOS transistor M3 is controlled by the output of the second operational amplifier OP2. In this embodiment, the non-inverting and inverting input terminals of the second operational amplifier OP2 are respectively coupled to the first gold oxide semiconductor transistor and the second metal oxide semiconductor transistor M2. Bungee jumping. The voltage level control circuit 302 functions to make the first and second MOS transistors 与1 and M2 have the same gate voltage (the value is Vbat) to ensure the first and second gold oxides. The first and second currents h and 12 generated by the half-plate 1 and M2 are in a fixed ratio. Figure 4 is another embodiment of the present invention. The linear charger 400 has a frequency compensation circuit 402 more than the linear charger 300 of FIG. As in the embodiment of Figure 4, the frequency compensation circuit 402 includes a plurality of resistors (I and R2), a voltage dividing point 404, a frequency compensator 406, and a variable capacitor C. The resistors I and R2 and the voltage dividing point 404 are connected in series between the battery module 408 and a ground terminal. The potential Vbaj of the battery module is outputted by the voltage dividing point 404 to the multiplex selection device 410 after the voltages 1 and R2 are divided. The frequency compensator 406 is coupled between the battery module 408 and the voltage dividing point 404. The variable capacitor C is coupled between the frequency compensator 406 and the ground terminal. In the constant voltage charging mode, the frequency compensation circuit 402

Client’s Docket No.:VIT06-0146 TT’s Docket No:0608-A41004-TW/Final /Glorious_Tien 11 1325672 該極點的頻率較高。因此m高頻的補償零點以得到 較高的相位邊際。第5圖之實施例藉由該第一電容Ci、該 第二電容C2、該開關sw、以及該比較器CMP達到上述需 求。如圖所示，該第三參考電位义把耦接比較器之 非反相輸入端’並且該感測電位Vsns耦接比較器之反 相輸入端。在該低負載電流的狀況下，該感測Client’s Docket No.: VIT06-0146 TT’s Docket No: 0608-A41004-TW/Final /Glorious_Tien 11 1325672 The frequency of this pole is higher. Therefore m compensates for the zero point of the high frequency to obtain a higher phase margin. The embodiment of Fig. 5 achieves the above demand by the first capacitor Ci, the second capacitor C2, the switch sw, and the comparator CMP. As shown, the third reference potential is coupled to the non-inverting input of the comparator and the sense potential Vsns is coupled to the inverting input of the comparator. The sensing is performed under the condition of low load current

km- Ύ sns I 降至低於該第三參考電位Vref3。該比較器CMP令該開關 SW導通。此時，該補償零點的值為1/(Ri.(Ci+c2))。反之， 在該南負載電流的狀況下，該制€位¥咖上升至高過該 第三參考電位Vref3。該比較器CMP令該開關SW不導通。 此時，該補償零點的值為1/(R1.C1)。 第6圖為第5圖之實施例的變形，其中使用更多組的 上述第二電容(C21、C2r..c2n)、該等第二電容所對應之開 關（SW!、SW2...SWn)、以及控制各開關的複數個比較器 (CMP!、CMP2."CMPn) 〇配合特職計的複數個參考電位 (Vrefsi、Vref32〜Vref3n) ’第6圖所示之線性充電器提供更多 補償零點供系統選擇。 本發明所揭露的電路不僅可作為線性充電器使用，亦 可用來作為低壓降穩壓器（Low Dr〇p 〇ut regulat〇r，LD0 regulator)。 本發明雖以較佳實施例揭露如上，然其並非用以限定 本發明的範圍’任何熟習此項技藝者，在不脫離本發明之 精神和範圍内，當可做些許的更動與潤飾，因此本發明之 保護範圍當視後附之申請專利範圍所界定者為準。Km- Ύ sns I falls below the third reference potential Vref3. The comparator CMP turns the switch SW on. At this time, the value of the compensation zero point is 1/(Ri.(Ci+c2)). On the contrary, in the case of the south load current, the maker ¥¥ coffee rises above the third reference potential Vref3. The comparator CMP causes the switch SW to be non-conducting. At this time, the value of the compensation zero is 1/(R1.C1). Figure 6 is a variation of the embodiment of Figure 5, wherein more sets of the second capacitors (C21, C2r..c2n), switches corresponding to the second capacitors (SW!, SW2...SWn) are used. ), and a plurality of comparators (CMP!, CMP2."CMPn) that control each switch, and a plurality of reference potentials (Vrefsi, Vref32 to Vref3n) with the special meter. The linear charger shown in Fig. 6 provides more Multiple compensation zeros are available for system selection. The circuit disclosed in the present invention can be used not only as a linear charger but also as a low voltage drop regulator (Low Dr〇p 〇ut regulat〇r, LD0 regulator). The present invention has been disclosed in the above preferred embodiments, and is not intended to limit the scope of the present invention. As a matter of course, it is possible to make some modifications and retouchings without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

Client's Docket No.:VIT06-0146 TT*s Docket No:0608-A41004-TW/Final /Glorious_Tien 1325672 【圖式簡單說明】 第1圖為一傳統線性充電器之實施例； 第2圖為本發明之線性充電器的一實施例； 第3圖為本發明之線性充電器的另一實施例； 第4圖為本發明之線性充電器的另一實施例； 第5圖為本發明之線性充電器的另一實施例；以及 第6圖為本發明之線性充電器的另一實施例。 【主要元件符號說明】 100〜傳統線性充電器； 102〜電池模組； 104、106、108、110〜傳統線性充電器100之晶片部分 的針腳接點； 202〜第一電流產生器； 206〜多工選擇裝置； 200〜線性充電器； 204〜電流偵測器； 208〜電池模組； 302〜電壓準位控制電路； 402〜頻率補償電路； 406〜頻率補償器； 410〜多工選擇裝置； Q ~第一電容； 300〜線性充電器； 400〜線性充電器； 404〜分壓點； 408〜電池模組； 500〜線性充電器； C〜可變電容； C2、C21、C22、C2n〜第二電容， Cbat〜電池模組之電容；Client's Docket No.: VIT06-0146 TT*s Docket No: 0608-A41004-TW/Final /Glorious_Tien 1325672 [Simplified Schematic] FIG. 1 is an embodiment of a conventional linear charger; FIG. 2 is a view of the present invention An embodiment of a linear charger; FIG. 3 is another embodiment of the linear charger of the present invention; FIG. 4 is another embodiment of the linear charger of the present invention; Another embodiment of the present invention; and FIG. 6 is another embodiment of the linear charger of the present invention. [Main component symbol description] 100~ conventional linear charger; 102~ battery module; 104, 106, 108, 110~ pin contact of the wafer portion of the conventional linear charger 100; 202~first current generator; 206~ Multiplex selection device; 200~ linear charger; 204~ current detector; 208~ battery module; 302~ voltage level control circuit; 402~ frequency compensation circuit; 406~ frequency compensator; 410~ multiplex selection device ; Q ~ first capacitor; 300 ~ linear charger; 400 ~ linear charger; 404 ~ voltage divider; 408 ~ battery module; 500 ~ linear charger; C ~ variable capacitor; C2, C21, C22, C2n ~ second capacitor, Cbat ~ capacitor of the battery module;

Cc、cz〜用於頻率補償的電容；Cc, cz~ capacitor for frequency compensation;

Client’s Docket N〇.:VIT06-0146 TT*s Docket No:0608-A41004-TW/Final /Glorious_Tien J4 1325672 cL〜負載電容； CMP、CMPi、CMP2、CMPn 〜比較器； gmp、gmnc、gmnv〜電晶體，Client's Docket N〇.:VIT06-0146 TT*s Docket No:0608-A41004-TW/Final /Glorious_Tien J4 1325672 cL~load capacitance; CMP, CMPi, CMP2, CMPn ~ comparator; gmp, gmnc, gmnv~ transistor ,

Ii與12〜第一與第二電流； 、M2、M3〜金氧半電晶體； mux!、mux]〜多工器； OPi、0P2、0P3〜運算放大器；Ii and 12~ first and second current; M2, M3~gold oxide semi-transistor; mux!, mux]~ multiplexer; OPi, 0P2, 0P3~ operational amplifier;

Ri、R2〜電阻； Rbat〜電池模組之電阻；Ri, R2 ~ resistance; Rbat ~ battery module resistance;

Rc、Rz〜用於頻率補償的電阻；Rc, Rz~ resistors for frequency compensation;

Rl〜負載電阻； Rsns〜感測電阻； SW、SWi、SW2、SWn〜開關；Rl ~ load resistance; Rsns ~ sense resistance; SW, SWi, SW2, SWn ~ switch;

Vbat〜電池模組之電位； VDD〜電源；Vbat ~ battery module potential; VDD ~ power supply;

Vg〜第一金氧半電晶體之閘極電位；a gate potential of Vg~first MOS transistor;

Vsns〜感測電位；Vsns~ sensing potential;

Vrefi、Vref2、Vref3、Vref3i、Vref32、Vref3n〜參考電位。Vrefi, Vref2, Vref3, Vref3i, Vref32, Vref3n~ reference potential.

Client's Docket N〇.:VIT06-0146 TT's Docket No:0608-A41004-TW/Final /Glorious_TienClient's Docket N〇.:VIT06-0146 TT's Docket No:0608-A41004-TW/Final /Glorious_Tien

Claims (1)

1325672 十、申請專利範圍： 1. 一種線性充電器，其中包括： 一第一電流產生器，產生一第一電流並且耦接一電池 模組，用以充電該電池模組； 一電流偵測器，耦接該第一電流產生器，用以產生對 應於該第一電流大小的一感測電位； ' 一第一運算放大器，具一第一及第二輸入端及一輸出 端，該輸出端耦接該第一電流產生器之一控制端；以及 • 一多工選擇裝置，用以在一定電流充電模式下，將一 第一參考電位以及該感測電位分別耦接至該第一運算放大 器之第一及第二輸入端，並且在一定電壓充電模式下，將 一第二參考電位以及該電池模組之電位分別耦接至該第一 運算放大器之第一及第二輸入端。 2. 如申請專利範圍第1項所述之線性充電器，其中該 第一電流產生器為一第一金氧半電晶體，其汲極耦接該電 池模組，並且其閘極耦接該第一運算放大器之輸出端作為 ® 該第一電流產生器之該控制端。 3. 如申請專利範圍第2項所述之線性充電器，其中該 電流偵測器包括一第二金氧半電晶體與一感測電阻，該第 二金氧半電晶體之汲極耦接該感測電阻並且其閘極與該第 一金氧半電晶體之閘極耦接在一起，藉以使流經該第二金 氧半電晶體的一第二電流比例於該第一電流，該感測電阻 將該第二電流轉換為該感測電位。 4. 如申請專利範圍第3項所述之線性充電器，其中該 Client’s Docket Νο.:νΐΤ06·0146 TT’s Docket No:0608-A41004-TW/Final /Glorious_Tien 1325672 第二金氧半電晶體之汲極與該感測電阻之間更包括一電壓 準位控制電路，其中包括： 一第三金氧半電晶體，其源極與汲極分別耦接該第二 金氧半電晶體之汲極與該感測電阻；以及 一第二運算放大器，其一第一輸入端以及一第二輸入 端分別耦接該第二金氧半電晶體之汲極以及該第一金氧半 電晶體之汲極，並且其輸出端耦接該第三金氧半電晶體之 閘極。 5. 如申請專利範圍第3項所述之線性充電器，其中該 電池模組與該多工選擇裝置之間更包括一頻率補償電路， 其中包括： 複數個電阻以及一分壓點，串接於該電池模組以及一 接地端之間，該電池模組之電位經該等電阻分壓後由該分 壓點輸出至該多工選擇裝置； 一頻率補償器，耦接於該電池模組與該分壓點之間； 以及 一可變電容，耦接該頻率補償器至該接地端； 其中，在該定電壓充電模式下，該頻率補償電路提供 一零點，其大小為該等電阻於該電池模組以及該分壓點之 間的電阻值乘以該可變電容後取倒數。 6. 如申請專利範圍第5項所述之線性充電器，其中該 可變電容包括： 一第一電容； 一開關以及一第二電容，該開關導通時，該第二電容 Clients Docket No. :VIT06-0146 IT’s Docket N〇:0608-A41004-TW/Final /Glorious Tien 17 1325672 - 並聯該第一電容； 一比較器，用以控制該開關，該比較器的一第一輸入 端與一第二輸入端分別輸入一第三參考電位與該感測電 位，藉以令該開關在一低負載電流的狀態下為導通，反之 為不導通。 7. 如申請專利範圍第5項所述之線性充電器，其中該 ' 可變電容可為金氧半電容。 8. 如申請專利範圍第1項所述之線性充電器，其中該 ® 感測電阻可為可變電阻。1325672 X. Patent application scope: 1. A linear charger, comprising: a first current generator, generating a first current and coupled to a battery module for charging the battery module; a current detector The first current generator is coupled to generate a sensing potential corresponding to the magnitude of the first current; 'a first operational amplifier having a first and a second input and an output, the output a control unit coupled to the first current generator; and a multiplex selection device for coupling a first reference potential and the sensing potential to the first operational amplifier in a current charging mode The first and second input terminals, and in a certain voltage charging mode, couple a second reference potential and a potential of the battery module to the first and second input ends of the first operational amplifier. 2. The linear charger of claim 1, wherein the first current generator is a first MOS transistor, the drain is coupled to the battery module, and the gate is coupled to the gate The output of the first operational amplifier acts as the control terminal of the first current generator. 3. The linear charger of claim 2, wherein the current detector comprises a second MOS transistor and a sense resistor, and the second MOS transistor is coupled to the drain The sensing resistor and its gate are coupled to the gate of the first MOS transistor, such that a second current flowing through the second MOS transistor is proportional to the first current, A sense resistor converts the second current to the sense potential. 4. The linear charger described in claim 3, wherein the Client's Docket Νο.: νΐΤ06·0146 TT's Docket No: 0608-A41004-TW/Final /Glorious_Tien 1325672 The second gold oxide semi-transistor Further comprising a voltage level control circuit, comprising: a third MOS transistor, wherein the source and the drain are respectively coupled to the drain of the second MOS transistor and the a second operational amplifier, wherein a first input end and a second input end are respectively coupled to the drain of the second MOS transistor and the drain of the first MOS transistor; And an output end thereof is coupled to the gate of the third MOS transistor. 5. The linear charger of claim 3, wherein the battery module and the multiplex selection device further comprise a frequency compensation circuit, including: a plurality of resistors and a voltage dividing point, connected in series Between the battery module and a grounding terminal, the potential of the battery module is divided by the resistors and outputted to the multiplex selection device by the voltage dividing point; a frequency compensator coupled to the battery module And a variable capacitor coupled to the ground compensator; wherein, in the constant voltage charging mode, the frequency compensating circuit provides a zero point, the size of which is the resistance The resistance value between the battery module and the voltage dividing point is multiplied by the variable capacitor and then counted down. 6. The linear charger of claim 5, wherein the variable capacitor comprises: a first capacitor; a switch and a second capacitor, the second capacitor Clients Docket No. when the switch is turned on: VIT06-0146 IT's Docket N〇:0608-A41004-TW/Final /Glorious Tien 17 1325672 - Parallel the first capacitor; a comparator for controlling the switch, a first input and a second of the comparator The input terminal respectively inputs a third reference potential and the sensing potential, so that the switch is turned on in a state of low load current, and vice versa. 7. The linear charger of claim 5, wherein the variable capacitor is a gold oxide half capacitor. 8. The linear charger of claim 1, wherein the sensing resistor is a variable resistor. Client’s Docket N〇.:VIT06-0146 TT^ Docket No:0608-A41004-TW/Final /Glorious_TienClient’s Docket N〇.:VIT06-0146 TT^ Docket No:0608-A41004-TW/Final /Glorious_Tien