TWI489285B - Adaptive usb charging method and system - Google Patents

適應性通用串列匯流排充電方法及系統 Adaptive universal serial bus charging method and system

本發明係有關通用串列匯流排(USB)技術，特別是關於一種適應性USB充電方法及系統。 The present invention relates to universal serial bus (USB) technology, and more particularly to an adaptive USB charging method and system.

根據通用串列匯流排(USB)的規範，連接至主機(host)的USB裝置至多僅能汲取500mA(毫安)的電流。由於有愈來愈多的USB裝置藉由主機，例如個人電腦，的USB埠來汲取電流以對USB裝置進行充電，因而有一些充電規範的制訂，例如Battery Charging Specification以及APPLE USB Power Adaptor。 According to the Universal Serial Bus (USB) specification, a USB device connected to a host can only draw up to 500 mA (mA). As more and more USB devices draw current through a USB port of a host computer, such as a personal computer, to charge the USB device, there are some charging specifications, such as the Battery Charging Specification and the APPLE USB Power Adaptor.

然而，當電腦在休眠或關機模式時，傳統USB裝置僅能選擇一種USB充電模式以進行充電。當拔除USB裝置後再插入支援另一USB充電模式的USB裝置時，會發生無法充電或僅能以先前的USB充電模式進行充電。 However, when the computer is in the sleep or power-off mode, the conventional USB device can only select one USB charging mode for charging. When a USB device that supports another USB charging mode is plugged in after removing the USB device, charging may occur or charging may be performed only in the previous USB charging mode.

此外，傳統USB充電電路一般係製造為外接USB充電器的形式，使得使用者必須額外購買一USB充電器，不但增加花費又增加使用上的不便。 In addition, the conventional USB charging circuit is generally manufactured in the form of an external USB charger, so that the user must purchase an additional USB charger, which not only increases the cost but also increases the inconvenience in use.

因此，亟需提出一種新穎的USB充電機制，除了解決前述無法改變充電模式或者無法充電的問題，還能減少電路面積。 Therefore, it is urgent to propose a novel USB charging mechanism, in addition to solving the aforementioned problem that the charging mode cannot be changed or cannot be charged, and the circuit area can be reduced.

鑑於上述，本發明實施例提出一種適應性USB充電方法及系統，藉以對一些USB裝置，使得當其返回正常電源狀態時，仍可偵測到該USB裝置。此外，本實施例之USB裝置進入低電源狀態時，如果使用者拔除USB裝置並再插入其他USB裝置，則可適應性地改變為其所支援的USB充電模式，以對USB裝置進行充電。再者，本實施例之充電系統可整合至主機，因而得以節省電路面積及製造成本。 In view of the above, the embodiment of the present invention provides an adaptive USB charging method and system, so that some USB devices can still detect the USB device when it returns to the normal power state. In addition, when the USB device of the embodiment enters the low power state, if the user removes the USB device and then inserts another USB device, the USB charging mode supported by the USB device can be adaptively changed to charge the USB device. Furthermore, the charging system of the present embodiment can be integrated into the host, thereby saving circuit area and manufacturing cost.

根據本發明實施例，於低電源狀態下，以一非USB標準充電模式對一USB裝置進行充電。當偵測耦接至USB裝置的一資料信號沒有變化，則維持非USB標準充電模式。當偵測資料信號有變化，並且該變化維持一第一時間，則切換至第三專屬充電模式。 According to an embodiment of the invention, a USB device is charged in a non-USB standard charging mode in a low power state. When detecting that a data signal coupled to the USB device has not changed, the non-USB standard charging mode is maintained. When the detected data signal changes and the change is maintained for a first time, the mode is switched to the third exclusive charging mode.

10‧‧‧CDP偵測單元 10‧‧‧CDP detection unit

12A‧‧‧第一比較器 12A‧‧‧First Comparator

12B‧‧‧第二比較器 12B‧‧‧Second comparator

14‧‧‧邏輯轉換單元 14‧‧‧Logical conversion unit

20-29‧‧‧步驟 20-29‧‧‧Steps

42-48B‧‧‧步驟 42-48B‧‧‧Steps

D+_in‧‧‧正資料輸入端 D+_in‧‧‧ positive data input

D-_in‧‧‧負資料輸入端 D-_in‧‧‧ negative data input

D+_out‧‧‧正資料輸出端 D+_out‧‧‧ positive data output

D-_out‧‧‧負資料輸出端 D-_out‧‧‧negative data output

R1-R9‧‧‧電阻 R1-R9‧‧‧ resistance

SW‧‧‧開關 SW‧‧ switch

Vref1‧‧‧第一參考電壓 Vref1‧‧‧ first reference voltage

Vref2‧‧‧第二參考電壓 Vref2‧‧‧second reference voltage

DMSE‧‧‧第一比較結果 DMSE‧‧‧ first comparison result

DPSE‧‧‧第二比較結果 DPSE‧‧‧ second comparison result

DMLCHG‧‧‧數位邏輯值 DMLCHG‧‧‧ digital logic value

DPICHG‧‧‧數位邏輯值 DPICHG‧‧‧ digital logic value

第一圖顯示本發明實施例之適應性USB充電系統。 The first figure shows an adaptive USB charging system in accordance with an embodiment of the present invention.

第二A圖及第二B圖顯示本發明實施例之USB充電方法的流程圖。 2A and 2B show a flow chart of a USB charging method according to an embodiment of the present invention.

第三圖顯示第一圖之信號DPSE與DMSE的示意圖。 The third figure shows a schematic diagram of the signals DPSE and DMSE of the first figure.

第一圖顯示本發明實施例之適應性通用串列匯流排(USB)充電系統，第二A圖及第二B圖則顯示本發明實施例之USB充電方法的流程圖。本實施例所示之充電系統可和主機(host)整合在一起，也可是獨立於主機之外。整合的好處在於讓充電系統可共用主機的控制器(未顯示於圖式中)，因而得以 節省相關電路面積及製造成本。本發明可適用於USB的各種規格，例如USB 3.0。此外，本說明書所提到之主機，其可泛指其他的裝置，例如集線器(hub)。以下實施例所提到之電源狀態，例如S0、S3、S4、S5，係依據進階組態及電源介面(advanced configuration and power interface,ACPI)所定義者，但不以此為限。其中，S0表示工作(working)狀態，S3表示待機(standby)狀態，S4表示休眠(hibernation)狀態，而S5表示關機(soft off)狀態。上述的S3、S4及S5也可統稱為低電源狀態，而上述的S0可稱為正常電源狀態。 The first figure shows an adaptive universal serial bus (USB) charging system according to an embodiment of the present invention, and the second A and second B diagrams show a flow chart of the USB charging method according to the embodiment of the present invention. The charging system shown in this embodiment can be integrated with a host or independently of the host. The benefit of integration is that the charging system can share the controller of the host (not shown in the figure), thus enabling Save relevant circuit area and manufacturing costs. The present invention is applicable to various specifications of USB, such as USB 3.0. In addition, the host mentioned in this specification may refer to other devices, such as a hub. The power states mentioned in the following embodiments, such as S0, S3, S4, and S5, are defined by the advanced configuration and power interface (ACPI), but are not limited thereto. Among them, S0 represents a working state, S3 represents a standby state, S4 represents a hibernation state, and S5 represents a soft off state. The above S3, S4 and S5 can also be collectively referred to as a low power state, and the above S0 can be referred to as a normal power state.

在本實施例中，USB充電系統包含一對差分資料輸入端：正資料輸入端D+_in及負資料輸入端D-_in，可分別耦接至USB裝置的正資料輸入接腳及負資料輸入接腳。USB充電系統包含一對差分資料輸出端：正資料輸出端D+_out及負資料輸出端D-_out，可耦接至主機。本實施例包含四個充電模式：標準下傳埠(standard downstream port,SDP)充電模式、充電下傳埠(charging downstream port,CDP)充電模式、專屬充電埠(dedicated charging port,DCP)充電模式及非USB標準充電模式。其中，SDP充電模式、CDP充電模式及DCP充電模式規範於Battery Charging Specification，而非USB標準充電模式則沒有規範於Battery Charging Specification中。在一實施例中，上述非標準充電模式為APPLE充電模式，其規範於APPLE USB Power Adaptor。本實施例使用二位元暫存器C1/C2，其藉由控制開關SW而得以選擇其中一種充電模式，然而並不以此為限。在一實施例中，主機控制器(未顯示出)之一韌體依據本發明充電方法來設定上述二位元暫存器之值C1與C2，以在不同情況切換不同的充電模式。 In this embodiment, the USB charging system includes a pair of differential data input terminals: a positive data input terminal D+_in and a negative data input terminal D-_in, which can be respectively coupled to a positive data input pin and a negative data input of the USB device. Pin. The USB charging system includes a pair of differential data outputs: a positive data output D+_out and a negative data output D-_out, which can be coupled to the host. The embodiment includes four charging modes: a standard downstream port (SDP) charging mode, a charging downstream port (CDP) charging mode, a dedicated charging port (DCP) charging mode, and Non-USB standard charging mode. Among them, the SDP charging mode, the CDP charging mode and the DCP charging mode are standardized in the Battery Charging Specification, while the non-USB standard charging mode is not standardized in the Battery Charging Specification. In an embodiment, the non-standard charging mode described above is an APPLE charging mode, which is specified in the APPLE USB Power Adaptor. This embodiment uses a two-bit register C1/C2, which is selected by controlling the switch SW, but is not limited thereto. In one embodiment, one of the host controllers (not shown) firmware sets the values C1 and C2 of the two-bit register in accordance with the charging method of the present invention to switch between different charging modes in different situations.

茲說明四種充電模式如下：(1)於SDP充電模式時，差分資料輸入端D+_in/D-_in耦接至差分資料輸出端D+_out/D-_out。於此充電模式下，可同 時進行USB資料傳輸及USB充電，其充電電流最大為500mA。(2)於CDP充電模式時，差分資料輸入端D+_in/D-_in耦接至差分資料輸出端D+_out/D-_out。於此充電模式下，可同時進行USB資料傳輸及USB充電，其充電電流最大為1.5A。CDP充電模式和SDP充電模式的主要差異在於，CDP充電模式可使用CDP偵測單元10進行信號交換(handshaking)機制以偵測CDP充電模式。(3)於DCP充電模式時，差分資料輸入端D+_in/D-_in與差分資料輸出端D+_out/D-_out斷開，且差分資料輸入端D+_in/D-_in耦接至一電阻R5。於此充電模式下，僅進行USB充電，但不進行USB資料傳輸。(4)非USB標準充電模式(例如針對APPLE裝置的充電模式)，又分為第一電流充電模式及第二電流充電模式；前者的充電電流可達1A(例如為APPLE 1A充電模式)，而後者的充電電流可達2A(例如為APPLE 2A充電模式)。於非USB標準充電模式時，差分資料輸入端D+_in/D-_in與差分資料輸出端D+_out/D-_out斷開，且差分資料輸入端D+_in/D-_in耦接至一特定分壓電路。其中，於第一電流充電模式下，分壓電阻R6/R7提供2.0V(伏特)給正資料輸入端D+_in，而分壓電阻R3/R4提供2.7V給負資料輸入端D-_in；於第二電流充電模式下，分壓電阻R8/R9提供2.7V給正資料輸入端D+_in，而分壓電阻R1/R2提供2.0V給負資料輸入端D-_in。 The four charging modes are as follows: (1) In the SDP charging mode, the differential data input D+_in/D-_in is coupled to the differential data output D+_out/D-_out. In this charging mode, the same USB data transmission and USB charging, the maximum charging current is 500mA. (2) In the CDP charging mode, the differential data input terminal D+_in/D-_in is coupled to the differential data output terminal D+_out/D-_out. In this charging mode, USB data transmission and USB charging can be performed at the same time, and the charging current is at most 1.5A. The main difference between the CDP charging mode and the SDP charging mode is that the CDP charging mode can use the CDP detecting unit 10 to perform a handshaking mechanism to detect the CDP charging mode. (3) In the DCP charging mode, the differential data input terminal D+_in/D-_in is disconnected from the differential data output terminal D+_out/D-_out, and the differential data input terminal D+_in/D-_in is coupled to A resistor R5. In this charging mode, only USB charging is performed, but USB data transmission is not performed. (4) Non-USB standard charging mode (for example, charging mode for APPLE device), which is further divided into a first current charging mode and a second current charging mode; the former charging current can reach 1A (for example, APPLE 1A charging mode), and The latter can charge up to 2A (for example, the APPLE 2A charging mode). In the non-USB standard charging mode, the differential data input terminal D+_in/D-_in is disconnected from the differential data output terminal D+_out/D-_out, and the differential data input terminal D+_in/D-_in is coupled to one. Specific voltage divider circuit. Wherein, in the first current charging mode, the voltage dividing resistor R6/R7 provides 2.0V (volts) to the positive data input terminal D+_in, and the voltage dividing resistor R3/R4 provides 2.7V to the negative data input terminal D-_in; In the second current charging mode, the voltage dividing resistor R8/R9 provides 2.7V to the positive data input terminal D+_in, and the voltage dividing resistor R1/R2 provides 2.0V to the negative data input terminal D-_in.

舉例來說，在第一圖的實施例中，當C1與C2皆為0時，表示充電模式有可能是CDP充電模式或SDP充電模式。當C1為0，C2為1，表示充電模式為非USB標準充電模式，其以第一電流進行充電。當C1為1，C2為0，表示充電模式為非USB標準充電模式，其以第二電流進行充電。當C1與C2皆為1時，表示充電模式為DCP充電模式。但C1與C2的設定不以此為限制。 For example, in the embodiment of the first figure, when both C1 and C2 are 0, it indicates that the charging mode may be a CDP charging mode or an SDP charging mode. When C1 is 0 and C2 is 1, it indicates that the charging mode is a non-USB standard charging mode, which is charged with the first current. When C1 is 1, C2 is 0, indicating that the charging mode is a non-USB standard charging mode, which is charged with the second current. When both C1 and C2 are 1, it indicates that the charging mode is the DCP charging mode. However, the settings of C1 and C2 are not limited by this.

參考第二A圖，初始時，於正常電源狀態S0下，預先設定二位元暫存器C1、C2的值以運作於一預設之充電模式(步驟20)。在一實施例中，在此預設之充電模式時，差分資料輸入端D+_in/D-_in耦接至差分資料輸出端D+_out/D-_out，故可同時進行USB資料傳輸及USB充電(例如當C1為0，C2為0的充電模式)。接著，在本實施例中，於正常電源狀態S0下，以CDP偵測單元10(第一圖)偵測USB裝置是否支援CDP充電模式(步驟21)。如果為是，則於步驟25，以CDP充電模式對USB裝置進行充電，並且在進入S3/S4/S5狀態時，仍維持CDP充電模式，同時保持USB電源VBUS。當電源狀態從低電源狀態S3/S4/S5進入正常電源狀態S0時(步驟26)，切換回預設的充電模式。 Referring to the second A picture, initially, in the normal power state S0, the values of the two bit registers C1, C2 are preset to operate in a predetermined charging mode (step 20). In an embodiment, in the preset charging mode, the differential data input terminal D+_in/D-_in is coupled to the differential data output terminal D+_out/D-_out, so that USB data transmission and USB can be simultaneously performed. Charging (for example, when C1 is 0 and C2 is 0). Next, in the present embodiment, in the normal power state S0, the CDP detecting unit 10 (first map) detects whether the USB device supports the CDP charging mode (step 21). If YES, then in step 25, the USB device is charged in the CDP charging mode, and when entering the S3/S4/S5 state, the CDP charging mode is maintained while maintaining the USB power source VBUS. When the power state enters the normal power state S0 from the low power state S3/S4/S5 (step 26), it switches back to the preset charging mode.

如果步驟21的偵測結果判定USB裝置不支援CDP充電模式，接著，於步驟22判斷USB裝置是否支援高速(high-speed)或以上速度(例如超高速(super-speed)。如果不支援高速或以上速度，例如支援低速(low-speed)或全速(full-speed)，則於步驟23，以SDP充電模式對USB裝置進行充電，並且在進入S3/S4/S5狀態時，仍維持SDP充電模式，同時保持USB電源VBUS。當電源狀態從低電源狀態S3/S4/S5進入正常電源狀態S0時(步驟24)，切換為預設的充電模式。流程回到步驟21。 If the detection result of step 21 determines that the USB device does not support the CDP charging mode, then in step 22, it is determined whether the USB device supports high-speed or higher speed (for example, super-speed). If high speed or The above speed, for example, supporting low-speed or full-speed, in step 23, charging the USB device in the SDP charging mode, and maintaining the SDP charging mode when entering the S3/S4/S5 state. While maintaining the USB power supply VBUS, when the power state enters the normal power state S0 from the low power state S3/S4/S5 (step 24), it switches to the preset charging mode. The flow returns to step 21.

如果步驟22的結果判定USB裝置支援高速或以上速度，則於步驟27，以SDP充電模式對USB裝置進行充電。當電源狀態從正常電源狀態S0進入低電源狀態S3/S4/S5時(步驟28)，則切換至一非USB標準充電模式。在一實施例中，在切換至非USB標準充電模式之前或同時，切斷USB電源VBUS一段時間，例如一秒鐘，再連接USB電源VBUS，並進入非USB標準充電模式，其細節將於 後面詳述。當電源狀態從低電源狀態S3/S4/S5進入正常電源狀態S0時(步驟29)，則切換至預設的充電模式。 If the result of step 22 determines that the USB device supports high speed or higher, then in step 27, the USB device is charged in the SDP charging mode. When the power state enters the low power state S3/S4/S5 from the normal power state S0 (step 28), it switches to a non-USB standard charging mode. In an embodiment, before switching to the non-USB standard charging mode, or simultaneously, the USB power supply VBUS is turned off for a period of time, for example, one second, then the USB power supply VBUS is connected, and the non-USB standard charging mode is entered, the details will be Detailed later. When the power state enters the normal power state S0 from the low power state S3/S4/S5 (step 29), it switches to the preset charging mode.

根據第二A圖所示的流程，對於支援低速、全速或CDP充電模式之USB裝置，當電源狀態從正常電源狀態S0進入低電源狀態S3/S4/S5時，不會切換USB充電模式，也不需切斷USB電源VBUS；當返回正常電源狀態S0時，仍可偵測到該USB裝置。另一方面，對於支援高速或以上速度但不支援CDP充電模式之USB裝置，當電源狀態從正常電源狀態S0進入低電源狀態S3/S4/S5時，則會切換充電模式，且需斷、接USB電源VBUS。 According to the flow shown in FIG. A, for the USB device supporting the low-speed, full-speed or CDP charging mode, when the power state is changed from the normal power state S0 to the low power state S3/S4/S5, the USB charging mode is not switched, It is not necessary to cut off the USB power supply VBUS; when returning to the normal power state S0, the USB device can still be detected. On the other hand, for a USB device that supports high speed or higher speed but does not support the CDP charging mode, when the power state enters the low power state S3/S4/S5 from the normal power state S0, the charging mode is switched, and the battery mode needs to be disconnected and connected. USB power supply VBUS.

切換至非標準USB充電模式(步驟28)之後，在本實施例中，如第二B圖所示，於步驟42，主機控制器(未顯示出)之韌體會設定上述二位元暫存器之值C1與C2，以切換至第一電流充電模式(在本說明書中又稱為第一專屬充電模式)或是第二電流充電模式(在本說明書中又稱為第二專屬充電模式)，選擇上述一種充電模式運行以對連接裝置進行充電。接著，於步驟43A或43B，偵測差分資料輸入端D+_in/D-_in的信號是否有變化，並且該變化是否維持一第一時間。在本實施例中，差分資料輸入端D+_in/D-_in的信號變化偵測是使用第一比較器12A(第一圖)將正資料輸入端D+_in與第一參考電壓Vref1作比較，以產生第一比較結果DMSE；並使用第二比較器12B將負資料輸入端D-_in與第二參考電壓Vref2作比較，以產生第二比較結果DPSE。接著，邏輯轉換單元14將第一比較結果DMSE與第二比較結果DPSE轉換為二數位邏輯值DMLCHG、DPLCHG，其可儲存於暫存器。控制器的韌體則根據該二數位邏輯值DMLCHG、DPLCHG以判定差分資料輸入端D+_in/D-_in的信號是否有變化，並且該變化是否維持一第一時間。舉例來說，當該二數位邏輯值DMLCHG、DPICHG之一者發生轉態 變化，即表示差分資料輸入端D+_in/D-_in的信號有變化。如果沒有變化，則維持第一電流或第二電流充電模式(步驟44A或44B)。上述之第一比較器12A、第二比較器12B及邏輯轉換單元14統稱為偵測單元。在一實施例中，上述偵測單元包含兩個以上的比較器，用以比較差分資料輸入端D+_in/D-_in信號的變化範圍，而邏輯轉換單元14轉換為一或多個數位邏輯值，以供後續判斷使用。 After switching to the non-standard USB charging mode (step 28), in the embodiment, as shown in the second B, in step 42, the firmware of the host controller (not shown) sets the above-mentioned two-bit register. The values C1 and C2 are switched to a first current charging mode (also referred to as a first dedicated charging mode in this specification) or a second current charging mode (also referred to as a second exclusive charging mode in this specification), The above one charging mode operation is selected to charge the connecting device. Next, in step 43A or 43B, it is detected whether there is a change in the signal of the differential data input terminal D+_in/D-_in, and whether the change is maintained for a first time. In this embodiment, the signal change detection of the differential data input terminal D+_in/D-_in is to compare the positive data input terminal D+_in with the first reference voltage Vref1 using the first comparator 12A (first map). To generate a first comparison result DMSE; and compare the negative data input terminal D-_in with the second reference voltage Vref2 using the second comparator 12B to generate a second comparison result DPSE. Next, the logic conversion unit 14 converts the first comparison result DMSE and the second comparison result DPSE into two-digit logical values DMLCHG, DPLCHG, which can be stored in the temporary register. The firmware of the controller determines whether the signal of the differential data input terminal D+_in/D-_in changes according to the two-digit logical values DMLCHG, DPLCHG, and whether the change is maintained for a first time. For example, when one of the two-digit logical values DMLCHG and DPICHG is in a transition state The change means that the signal of the differential data input terminal D+_in/D-_in has changed. If there is no change, the first current or second current charging mode is maintained (step 44A or 44B). The first comparator 12A, the second comparator 12B and the logic conversion unit 14 described above are collectively referred to as a detection unit. In one embodiment, the detecting unit includes two or more comparators for comparing the variation range of the differential data input terminal D+_in/D-_in signal, and the logic converting unit 14 converts to one or more digit logics. Value for later use.

請配合第三圖，其為第一圖中之信號DPSE與DMSE的示意圖。如果步驟43A或43B經偵測而判定差分資料輸入端D+_in/D-_in的信號有變化，即表示信號DPSE與DMSE其中一者發生轉態變化(例如為低準位)，並且該變化維持一第一時間(例如時間T1)，則於步驟45A或45B，清除該二數位邏輯值DMLCHG、DPLCHG，並切換至DCP充電模式(在本說明書中又稱為第三專屬充電模式)。接著，於步驟46A或46B，控制器計時一第二時間(例如時間T2)，並於第二時間計時結束時，於步驟47A或47B，切換至第一電流或第二電流充電模式。與此同時，USB電源VBUS繼續維持，因此，當第二時間計時結束時而切換回第一電流或第二電流充電模式時，仍然能持續對USB裝置進行充電。接著流程回到步驟44A或44B，維持第一電流或第二電流充電模式。接著，於步驟48A或48B，計時一第三時間(例如時間T3)，判斷該第三時間是否等於一固定時間。若是，則進行步驟43A或43B，繼續偵測差分資料輸入端D+_in/D-_in的信號是否有變化，並且該變化是否維持第一時間(例如時間T1)，否則進行步驟44A或44B。本發明的流程即依此方式運行。上述的第一時間、第二時間、第三時間、固定時間的長短皆可依照設計者的需求被編程(program)。 Please cooperate with the third figure, which is a schematic diagram of the signals DPSE and DMSE in the first figure. If the step 43A or 43B detects that the signal of the differential data input terminal D+_in/D-_in changes, that is, the signal DPSE and the DMSE change in a transition state (for example, a low level), and the change Maintaining a first time (eg, time T1), in step 45A or 45B, the two-digit logic values DMLCHG, DPLCHG are cleared and switched to the DCP charging mode (also referred to as the third exclusive charging mode in this specification). Next, in step 46A or 46B, the controller counts a second time (e.g., time T2), and at the end of the second time period, in step 47A or 47B, switches to the first current or second current charging mode. At the same time, the USB power supply VBUS continues to be maintained, so that when the second time is over and switched back to the first current or the second current charging mode, the USB device can still be continuously charged. The flow then returns to step 44A or 44B to maintain the first current or second current charging mode. Next, in step 48A or 48B, a third time (for example, time T3) is counted to determine whether the third time is equal to a fixed time. If yes, proceed to step 43A or 43B to continue to detect whether there is a change in the signal of the differential data input terminal D+_in/D-_in, and whether the change is maintained for the first time (for example, time T1), otherwise proceed to step 44A or 44B. The flow of the present invention operates in this manner. The first time, the second time, the third time, and the fixed time length described above can all be programmed according to the designer's needs.

根據第二B圖的流程，當使用者連接的USB裝置為支援DCP充電模式的裝置，當連接的USB裝置未拔除時，在運行步驟48A或48B時，D+_in/D-_in 的信號仍會發生變化(如第三圖T3所示)。因此，計時第三時間，當第三時間小於一固定時間，則保持第一電流或第二電流充電模式以避免頻繁的切換充電模式。當第三時間等於一固定時間時，回到步驟43A或43B。由於系統並未切斷VBUS電源，因此充電系統仍能對該連接裝置進行充電。在一實施例中，當USB裝置被拔除時，仍能在該固定時間後，回到步驟43A或43B，藉此方式更可判斷該USB裝置是否被拔除。在另一個例子中，根據第二B圖的流程，在低電源狀態S3/S4/S5時，如果使用者拔除USB裝置並再插入一支援第一電流或第二電流充電模式的USB裝置，仍能藉由步驟47A或47B切換至第一電流或第二電流充電模式而得以進行充電。在另一個例子中，根據第二B圖的流程，在低電源狀態S3/S4/S5時，如果使用者拔除USB裝置並再插入一支援DCP充電模式的USB裝置，則會於步驟43A或43B偵測到差分資料輸入端D+_in/D-_in的信號變化，因而接著於步驟45A或45B切換至DCP充電模式進行充電。在一簡單的實施例中，本發明流程更不需要步驟48A與48B，也就是說，步驟44A與44B可以直接回到步驟43A與43B。簡而言之，當進入低電源狀態S3/S4/S5時，如果使用者拔除USB裝置並再插入其他USB裝置，則本實施例可適應性地改變為其所支援的USB充電模式，以對USB裝置進行充電。 According to the flow of FIG. B, when the USB device connected by the user is a device supporting the DCP charging mode, when the connected USB device is not removed, when running step 48A or 48B, D+_in/D-_in The signal will still change (as shown in Figure T3). Therefore, the third time is counted, and when the third time is less than a fixed time, the first current or the second current charging mode is maintained to avoid frequent switching of the charging mode. When the third time is equal to a fixed time, it returns to step 43A or 43B. Since the system does not cut off the VBUS power supply, the charging system can still charge the connection device. In an embodiment, when the USB device is removed, it is still possible to return to step 43A or 43B after the fixed time, thereby determining whether the USB device is unplugged. In another example, according to the flow of FIG. B, in the low power state S3/S4/S5, if the user removes the USB device and then inserts a USB device supporting the first current or the second current charging mode, Charging can be performed by switching to the first current or the second current charging mode by step 47A or 47B. In another example, according to the flow of the second B diagram, in the low power state S3/S4/S5, if the user removes the USB device and then inserts a USB device supporting the DCP charging mode, it will be in step 43A or 43B. The signal change of the differential data input terminal D+_in/D-_in is detected, and then the battery is switched to the DCP charging mode for charging in step 45A or 45B. In a simple embodiment, the process of the present invention does not require steps 48A and 48B, i.e., steps 44A and 44B may return directly to steps 43A and 43B. In short, when the user enters the low power state S3/S4/S5, if the user removes the USB device and then inserts another USB device, the embodiment can adaptively change the USB charging mode supported by the user. The USB device is charged.

回到第二A圖，當電源狀態從低電源狀態S3/S4/S5回到正常電源狀態S0時(步驟29)，則切換回預設之充電模式(例如當C1為0，C2為0的充電模式)。在切換充電模式之前或同時，切斷USB電源VBUS一段時間，例如一秒鐘，再連接USB電源VBUS，並進入正常電源狀態S0。流程回到步驟21。其中，在該預設之充電模式時，該USB裝置可同時進行USB資料傳輸及USB充電。 Returning to the second A picture, when the power state returns from the low power state S3/S4/S5 to the normal power state S0 (step 29), it switches back to the preset charging mode (for example, when C1 is 0 and C2 is 0) Charging mode). Before or at the same time, the USB power supply VBUS is turned off for a period of time, for example, one second, and then the USB power supply VBUS is connected, and the normal power supply state S0 is entered. The flow returns to step 21. Wherein, in the preset charging mode, the USB device can simultaneously perform USB data transmission and USB charging.

另外，當充電系統耦接一支援DCP充電模式的USB裝置，當流程運行到步驟45A/45B時，可利用實體電路設計的方式，使得充電系統偵測到該USB裝置已被拔除，便直接切換至非USB標準充電模式。也就是說，不需要再等待第二時間計時結束(步驟46A/46B)。因此，針對上述情況，可以更快速地切換充電模式。以下將詳細說明。 In addition, when the charging system is coupled to a USB device supporting the DCP charging mode, when the process runs to the step 45A/45B, the physical circuit design manner can be utilized, so that the charging system detects that the USB device has been removed, and directly switches. To non-USB standard charging mode. That is, there is no need to wait for the second time to end (step 46A/46B). Therefore, for the above case, the charging mode can be switched more quickly. The details will be described below.

再參考第一圖，充電系統耦接一支援DCP充電模式的USB裝置。當開關SW切換至DCP充電模式時(亦即當流程運行到步驟45A/45B時)，一控制電路15用以偵測差分資料信號D+_in/D-_in的電壓準位，並根據量測到的電壓準位來控制一上拉(pull-high)電阻或是一下拉(pull-low)電阻耦接至差分資料信號D+_in/D-_in的一端。支援DCP充電模式的USB裝置耦接第一圖的充電系統時，可能會發生以下兩種情況。 Referring again to the first figure, the charging system is coupled to a USB device that supports the DCP charging mode. When the switch SW is switched to the DCP charging mode (that is, when the flow runs to the step 45A/45B), a control circuit 15 is used to detect the voltage level of the differential data signal D+_in/D-_in, and according to the measurement The voltage level is controlled to control a pull-high resistor or a pull-low resistor coupled to one end of the differential data signal D+_in/D-_in. When the USB device supporting the DCP charging mode is coupled to the charging system of the first figure, the following two situations may occur.

在一實施例中，在DCP充電模式時，當控制電路15偵測耦接的USB裝置使得差分資料信號D+_in/D-_in皆為高準位時，控制電路15控制一下拉電阻耦接至差分資料信號D+_in/D-_in的一端。當該USB裝置未拔除時，此下拉電阻並不會對充電功能造成影響；當該USB裝置被拔除時，此下拉電阻將會使得差分資料信號D+_in/D-_in被下拉至一參考電位(例如接地端)。也就是說，該USB裝置被拔除時，在差分資料信號D+_in/D-_in上發生由高準位轉低準位的一轉態變化。當偵測單元偵測到此轉態變化時，則充電系統切換至非USB標準充電模式。 In an embodiment, in the DCP charging mode, when the control circuit 15 detects the coupled USB device such that the differential data signals D+_in/D-_in are all at a high level, the control circuit 15 controls the pull-up resistor coupling. To one end of the differential data signal D+_in/D-_in. When the USB device is not removed, the pull-down resistor does not affect the charging function; when the USB device is removed, the pull-down resistor will cause the differential data signal D+_in/D-_in to be pulled down to a reference potential. (eg ground). That is to say, when the USB device is removed, a transition state change from the high level to the low level occurs on the differential data signal D+_in/D-_in. When the detecting unit detects the change of the transition state, the charging system switches to the non-USB standard charging mode.

在另一實施例中，在DCP充電模式時，當控制電路15偵測耦接的USB裝置使得差分資料信號D+_in/D-_in皆為低準位時，控制電路15控制一上拉電阻耦接至差分資料信號D+_in/D-_in的一端。當該USB裝置未拔除時，此上拉 電阻並不會對充電功能造成影響；當該USB裝置被拔除時，此上拉電阻將會使得差分資料信號D+_in/D-_in被上拉至一高準位(例如3.3V)。也就是說，該USB裝置被拔除時，在差分資料信號D+_in/D-_in上發生由低準位轉高準位的一轉態變化。當偵測單元偵測到此轉態變化時，則充電系統切換至非USB標準充電模式。 In another embodiment, in the DCP charging mode, when the control circuit 15 detects the coupled USB device such that the differential data signals D+_in/D-_in are all at a low level, the control circuit 15 controls a pull-up resistor. It is coupled to one end of the differential data signal D+_in/D-_in. This pull-up is when the USB device is not removed The resistor does not affect the charging function; when the USB device is removed, this pull-up resistor will cause the differential data signal D+_in/D-_in to be pulled up to a high level (eg 3.3V). That is to say, when the USB device is removed, a transition state change from the low level to the high level occurs on the differential data signal D+_in/D-_in. When the detecting unit detects the change of the transition state, the charging system switches to the non-USB standard charging mode.

因此，在DCP充電模式時，藉由上述方式，充電系統能夠偵測到該USB裝置已被拔除，便直接切換至非USB標準充電模式，如此可以更快速地切換充電模式。 Therefore, in the DCP charging mode, by the above manner, the charging system can detect that the USB device has been removed, and directly switch to the non-USB standard charging mode, so that the charging mode can be switched more quickly.

以上所述僅為本發明之較佳實施例而已，並非用以限定本發明之申請專利範圍；凡其它未脫離發明所揭示之精神下所完成之等效改變或修飾，均應包含在下述之申請專利範圍內。 The above description is only the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention; all other equivalent changes or modifications which are not departing from the spirit of the invention should be included in the following Within the scope of the patent application.

28‧‧‧步驟 28‧‧‧Steps

42-48B‧‧‧步驟 42-48B‧‧‧Steps