TWI294256B - Charge pump drive circuit for a light emitting diode - Google Patents

Description

1294256 IX. Description of the Invention: [Technical Field of the Invention] In particular, the present invention relates to a charge pump driving circuit for a charge pump driving circuit for a light emitting diode. [Prior Art] Figure! (4) Display a conventional charge pump drive circuit 1 〇 <Detailed view. The charge pump driving circuit 1 converts an input voltage source Vin into a voltage v- for driving the load U. In many cases, the input voltage may not be suitable for driving the negative 胄U directly. For example, if the input voltage source η: high, too low, or too large a disturbance occurs, it is necessary to: use the charge pump to drive the electricity $ 10 to adjust A properly sized and stable drive voltage vout. For example, the conventional charge drive circuit shown in FIG. 4(4) is provided with a charge pump 12 which alternately operates in a charging phase and a discharge according to the switching control signals SC1 and SC2 generated by the switching control circuit 13. In the stage, a driving voltage is generated equal to twice the input voltage source V i η . Specifically, the double charge pump 12 shown in Fig. 1(a) is composed of first to fourth switches S1 to S4 and a pump capacitor (pUmping capacit〇r) Cp. The first switch S 1 is coupled between the input voltage source Vin and the first electrode of the pump capacitor Cp; the second switch S2 is coupled between the input voltage source vin and the second electrode of the pump capacitor Cp; and the third switch S3 is coupled to the pump capacitor Cp The second electrode is connected to the ground potential; and the fourth switch S4 is coupled between the first electrode of the pump capacitor Cp and the driving voltage VQut. As shown in Figure 1(b), slave switching control

Vref, and a variable resistance unit VAR. The voltage detecting circuit 14 is directly connected to the output $ of the charge pump 12 for generating a feedback signal Vfb representing the driving voltage V〇ut. As shown in Figure i(a), the voltage detecting circuit 14 is implemented by a resistor divider, wherein the coupling point of the series resistors R1 and R2 provides a partial voltage [R2/(Rl+R2)]*V〇ut As the feedback signal Vfb. Based on the difference between the feedback signal Vfb and the reference voltage source Vref, the error amplifier generates a first blood generated by the circuit 1313, and the ^ ϊΥ ^ ^ one-switch control signals SCI and SC2 are non-overlapping with each other (non_overl. ▲ — P g) and a binary oscillating signal with a Η position and a low level l. The first switching and narrowing system SCI is applied to the first and third switches S1 and S3, and the second switching is performed as..., /, #弟一换拴制SC1 is applied to the second and fourth switches S 2 and S 4. At the charging stage ρ by the electric 丨 丰 feng, for example, time T1 to T2

And time T5 to T6, the first 盥 second „ M, the younger one switch S1 and S3 are in the conduction (〇N) state but the second and fourth switches S2 盥 S4 are more than +, ^ 』 兴 S4 are in non-conducting (OFF), so that the pump capacitor Cp is connected to the input voltage source Vin and the first electrode of the pump #Cp is connected to the ground potential. In the discharge phase, for example, time ...4 and time...8, the second and fourth switches S2 and S4 are in the on_state but the first and third switches_μ are in the non-conducting (〇FF) state, so that the first electrode of the transmissive Cp is connected to the driving The second electrode of the voltage Cp is connected to the input voltage source vin. By alternate operation of the charging phase and the discharging phase, the pump capacitor Cp provides twice the input voltage source Vin as the driving voltage v_. In order to maintain the driving voltage vout as expected The stable charge adjustment value; the conventional charge pump drive circuit 1G is further provided with a control system comprising a voltage detection circuit 14, an error amplifier A 5g js, a dual state 15 , a reference voltage source 1294256 An error number verr is used to control the variable resistance unit VAR. The variable resistance value of the variable resistance unit VAR is connected in series between the input voltage source Vin and the pump capacitor Cp, so that the charging current of the pump capacitor cp can be adjusted during the charging phase and the charging current of the pump capacitor Cp can be adjusted during the discharging phase. Change the driving voltage provided by the pump capacitor Cp. As a result, in steady state, feedback

The signal vfb is substantially adjusted to be equal to the reference voltage source Vw, in other words to simultaneously adjust the drive voltage accordingly. Finally, after the possible filter 16 removes the possible chopping, the desired driving voltage v(4) is supplied. Although the conventional charge pump driving circuit 1 shown in FIG. 1(4) can provide a stably adjusted driving voltage V〇 Ut to the load u, but in the case where the load u is a light-emitting diode (LED), the charge-based driving circuit f does not effectively control the brightness of the light-emitting diode because of the brightness of the light-emitting diode It is determined by the drive current rather than the drive voltage. Furthermore, in order for the light-emitting diode to be turned on, a conventional charge pump drives electricity. Unnecessarily excessive driving voltage v, 'dynamic efficiency. In view of the foregoing problems, the object of the present invention is to provide a driving circuit for driving a light-emitting diode, which can be light-charged and achieve better. Drive efficiency. * Especially brighter according to one aspect of the invention 'a charge i driving electric-light emitting diode' which comprises a charge pump, - switching control to drive I294256

w depletion circuit, an error amplifier, and a variable resistance unit. The charge is converted to an input voltage source to be a driving voltage for supply to the light emitting diode. The switching control circuit controls the charge pump to alternately operate in a charging stage slave and a discharging phase. The current regulating circuit has a current setting unit and a 2-machine adjusting unit. The current setting unit determines a reference current. The electric f adjusting unit has a current regulating end and a feedback detecting end. The current is tuned to the light emitting diode to control the flow through the light emitting diode motor proportional to the reference current. The feedback detection terminal provides a feedback ID which represents a current regulation characteristic voltage. The error amplifier generates an error signal based on the difference between the feedback signal and the source of the test power f. The under-resistance unit 70 is coupled between the input voltage source and the charge pump, and adjusts a variable resistance value in response to the error signal. In accordance with another aspect of the present invention, a charge pump driving method provides a predetermined drive Th 0 0 * 勒 % machine to a light emitting diode. The light-emitting diode has a first electrode, a fish, and an electrode. A charge pump is used to convert an input voltage source into a drive.兮+远电何泵 has at least one pump capacitor, the mother of the at least one pump electric valley will be New Zealand, / ', ,, and two by a number of switches and the handle is combined with the input voltage source and the driving .彳技. I should drive the voltage to the first + of the light-emitting diode, the electric circuit of the second circuit of the light-emitting diode

Extremely controlling the current flowing through one of the light-emitting diodes is equivalent to the predetermined drive current. One of the current regulation characteristic voltages of the current regulation circuit. Based on the difference between the current regulation characteristic voltage and the reference voltage source, a series connection is established between the input voltage source and the at least one pump capacitor. j 4夂 7 must be 4256 [Comprehensive mode] The following description and the accompanying drawings will make the description, features, and advantages of the present invention more obvious. DETAILED DESCRIPTION OF THE INVENTION Reference will now be made to the preferred embodiments of the invention. According to the present invention, the first embodiment of the present invention is used to convert a pump drive circuit θ ^ the voltage source Vin becomes a driving laser skull, and the first adjusted voltage V〇ut And q is the drive current J by the LED. The first fff hunting M drive a light-emitting diode H ” Example of the charge I drive circuit 20 mainly and ancient -1 What is the result 22, all shots l batch also 丨❿ &/; have an electric knife change control circuit 23, a power difference The amplifier 25 is operated by another π w gate, that is, the circuit 24, an error, and a variable resistance unit VAR. The charge pump 22 shown in Fig. 2 is implemented by a circuit configuration and operation method. 12, because I i % "; Figure 2 (a) 2 times the power will be further described. According to the switching control signal SC1贞SC2, the voltage produced by the road 23 V-' is equal to the input Voltage #生-(四) Road 2 3 The switching control generated by a L L Tiger SC1 and SC2 are also as shown in Figure 1 (^), so no further details are provided. The current regulating circuit 24 controls the household 铖 eight, the system / melon illuminating The driving current l of the diode LED is equal to a predetermined adjustment value, so that the brightness of the LED diode is controlled and maintained stable. Specifically, the current regulating circuit 24 has an electric m early το and n weeks of the military unit. The system determines a reference current Iref. The current regulating unit has a current regulating terminal coupled to the hair The second (four) (four) heart control flow through the light-emitting diode drive 294256, the dynamic current lout is equal to or proportional to the reference current Iref. The current adjustment unit further has a feedback detection terminal for providing a feedback signal Vfb, which represents One of the current regulating circuits 24 adjusts the characteristic voltage. In the embodiment shown in FIG. 2, the current setting unit is composed of a predetermined reference current source Iref and a transistor Q1, and the current regulating unit is composed of a transistor. Q2 and Q3 are formed by an operational amplifier 〇p. The transistors Q1 and Q2 form a current mirror structure, that is, the gate coupling of the transistor Q1.

The gate of the transistor Q2 is combined with the source of the transistor Q1 and the source of the transistor 搞^ to the ground potential; and the idle pole and the pole of the transistor Q1 are coupled to each other. Therefore, in the case where the reference current source is applied to the transistor (1), if the size of the transistor Q2 (that is, the width-to-length ratio of the current channel) is doubling the size of the transistor Q2, the drain of the transistor Q2 flows. The drive current will be the reference current source, U. In this case, the transistor Q2 is not used as a current regulating end, and is integrated with the cathode (n-pole) of the LED of the LED to make the adjusted driving current I-effectively drive the LED. The degree of the first current U and the reference current source Ir 2 is generated. In order to make the proportional relationship between the driving electric power and the ref 3 more precise, the zeta potential of the transistor is preferably adjusted to be equal to each other with the zeta potential of the plug of m ιμ φ ώ Q. Therefore, the operation of the current regulating unit forms a voltage follower circuit iv〇1t "body Q3". Specifically, the operation is amplified to the inverting input of the OP ^ ^ # ^ ^ ^ The drain of transistor Q1, and the non-inverting input terminal) is the adjustment of 03; K is σ into the drain of Q2 of the electric solar cell. The source of transistor Q3 is coupled to the crystal ^ ^ ^ Α ^ ^ ^ ^ The bungee of Q2, and the ultimate fault of the transistor Q3 is the reference current source. 输出 The output of the nose amplifier OP is controlled by 9 1294256 Q2 is the gate of the transistor Q3 'the transistor Q1' The pole and the transistor poles are adjusted to have potentials equal to each other.

> The charge pump driving circuit 20 according to the P embodiment of the present invention is driven by a solid-state current to drive the light-emitting diode coffee, thereby achieving the purpose of effectively controlling the light-emitting illuminance. However, the charge pump drive circuit 1G# which is not known in Fig. Ua) is driven by a fixed voltage, as described above, so that the intensity of the LED of the light-emitting diode cannot be effectively controlled. In the fixed current driving method according to the present invention, in order to ensure that the current regulating circuit 24 can perform the current regulating function, the drain of the transistor ... and the electrode of the transistor Q Q2 must maintain a high operating voltage to ensure the transistor. Both Q1 and Q2 operate in a saturation region (referred to as (10) R. Therefore, the charge pump driving circuit 20 according to the first embodiment of the present invention employs an operational amplifier, an inverting input terminal (0) of 0P as a feedback (four) terminal: As mentioned above, the inverting input terminal of the operational amplifier OP is integrated with the drain of the 2 crystal Q1, and the drain potential of the transistor Q1 is followed by the non-inverting input terminal (1) of the differential amplifier 11 〇P ( That is, the drain potential of the transistor Q2 varies. Therefore, the feedback signal provided from the feedback detection terminal represents the radian potential of the electric Japanese and Japanese bodies Q1 and Q2. Based on the feedback signal and the reference voltage The difference between the sources vref, the error amplifier 25 generates an error signal Verr' for controlling the variable resistance unit VAR. Since the variable resistance value of the variable resistance unit var is connected in series between the input voltage source Vin and the pump capacitor Cp, Can be adjusted during the charging phase The charging current of the capacitor Cp adjusts the charging current of the pumping valley Cp in the discharging phase, thereby changing the driving voltage VQut provided by the pump capacitor Cp. After the possible filter 26 removes the possible chopping, the driving voltage 10out The anode of the LED is supplied to the anode of the LED, and the variation of the driving voltage V." causes a change in the potential of the gate Q1 of the electric body Q1. Therefore, the transmission error is caused by the change of the driving voltage V. The signal verr and the variable resistance unit VAR can effectively adjust the feedback signal Vfb to be equal to the reference voltage source vref. Therefore, if the reference voltage source Vref is set high enough to allow the transistors Q1 and Q2 to operate in the saturation region, then The driving voltage Vcut can be adjusted to ensure that the current regulating circuit 24 can perform a current regulating operation to provide a driving current having a predetermined value. - The first is to source the source of k唬Vfb, according to the first aspect of the present invention. The charge pump driving power 4 20 of the embodiment is obviously different from the conventional electric pump driving circuit 1 Q shown in FIG. 1(4), and the m, _ port is directly adopted by the charge pump driving circuit 10 which is not known in FIG. 1(a). drive The dynamic voltage Vaut (or its divided voltage) is used as the feedback signal vfb 'only to maintain the driving voltage Vcut at a predetermined regulated voltage. However: the return credit of the charge pump driving circuit 2 according to the first embodiment of the present invention The number vfb is obtained by detecting the current regulating characteristic voltage of the current regulating circuit 24 (that is, the potential of the transistor Q1 and the Q2) to ensure the normal operation of the current regulating function. Further, according to the present invention The charge pump driving circuit 20 of an embodiment can reduce the generated driving voltage vout as much as possible, as long as it can maintain the current regulating operation of the current regulating circuit 24, so that the conventional charge pump driving as shown in Fig. i (4) can be achieved. Circuit 1 〇 better drive efficiency.

The variable resistance unit VAR is obtained by a MOS semi-transistor (MOS)

Transistor) is implemented by the equivalent on-resistance of the drain-to-source current path. Specifically, the drain-source current path coupling 11 1294256 of the MOS transistor is coupled between the input voltage source Vin and the charge pump 22, while the gate of the M〇s body is controlled by the error signal Verr. By the error signal ν. The equivalent on-resistance of the drain current source channel of Zhou Chu MOS transistor IsUiO, whether in the charging phase or the discharging phase, the input voltage is in / /, the current flowing between the charge pump 22 can be effectively controlled. 3 shows a detailed circuit diagram of a book pump circuit 30 for a light-emitting diode according to an embodiment of the present invention. The second embodiment is different from the first embodiment in the charge pump drive of the second embodiment. The circuit 3Q employs a multimode charge pump 32. Specifically, the multimode charge pump 32 has seven switches S1 to S7 and two pump capacitors Cpl and Cp2 coupled to each other to form a configuration as shown in Fig. 3. The multi-mode charge pump 32 can be operated in 1x, 1⁄5x mode, or 2x mode, in the 1x mode, in the control mode switch s丨 to S7 (ON) and non-conduction (〇FF). The switches 81 and S7 are maintained in a non-conducting (〇FF) state, and the switches are maintained in the V-on state by % and J, so the generated driving voltage v〇ut is equivalent to the input voltage source Vin. ^ at 1 · 5 In the double-twist type, the multi-mode charge pump 32 alternately performs the charging and discharging phases according to the switching control signal (6) generated by the switching control circuit 33, so that the generated driving voltage is 5 彳" Input voltage source Vin. When performing the charging phase, switch S 1. S3, S4, ite c (: |: 卜 " ” 6 white is maintained in the non-conducting (OFF) state, while the switches * S5 and S7 are maintained in the conducting (〇N) state. When the discharge phase is performed, the switch S2, S5, and 盥S7 are maintained in a non-conducting (OFF) state, while switches S1, S3, S4, and gold C / Γ α * ” S6 are maintained in a conducting (〇Ν) state. 12 1294256 In the double pull type, the multi-mode charge pump 32 alternately performs a charging slave slave and a discharge phase according to the switching control signals sC1 and SC2 generated by the switching control packet ^3, thereby causing the generated driving voltage. It is equivalent to twice the input voltage source Vin. When the charging phase is performed, the switches SI S2, S3, and S6 are maintained in a non-conducting (〇FF) state, and the switches S4 S5 and S7 are maintained in an ON state. When the discharge phase is performed, the two switches S2, S3, S4, S5, and S7 are maintained in a non-conducting (〇FF) state, and the switches S1 and S6 are maintained in an ON state. The operation mode of 32, the charge pump driving circuit 3 according to the second embodiment of the present invention has a mode The selection circuit 37 is configured to apply the _ mode selection signal (10) to the multi-mode charge fruit 32. The pull selection circuit 37 should detect any of the input voltage source Vin, the driving voltage, or the feedback (4)~ or a combination thereof. The multi-mode charge fruit 32 is set to the ι mode, the 15 mode, or the double mode. Since the input source is usually time-dependent, for example, when the input voltage source 4 is implemented, When entering the Gongyi, Tower λ, + inter-gas battery, multiple... At first, at a relatively high potential', the pump 32 is set to the lower rate mode, and the input voltage source is then at a relatively low potential, and ' The input is changed to set to the higher magnification mode.弋 & Ho pump 32 Another method is to determine how to determine the source V- and assist the mode selection I..., the operation mode of the loose charge pump 32 via the detection drive circuit 37. In the case of a multi-mode charge pump, it is still unable to provide a sufficiently large driving voltage W, that is, the mode is not multi-mode 13 1294256. The charge mill 32 may have to enter a mode higher than the currently set. The driving voltage V is provided when the multi-mode charge pump 32 operates in the higher rate mode. When an excessive phenomenon occurs, it means that the multi-turn charge pump 32 may have to enter a mode lower than the currently set one. In order to save unnecessary power consumption and improve driving efficiency. In still another method, the mode selection circuit 37 determines how to set the operation mode of the multi-mode charge pump 32 according to the feedback signal Vfb. Specifically, when multiple When the mode charge pump 32 operates in the lower rate mode, it is observed that the feedback signal vfb is lower than the reference voltage source Vref, and the current regulating circuit 34 cannot provide the required driving current W, that is, the multiple:: 32 may have to enter a higher rate than the currently set. Conversely, the Tianzhong heavy mode charge pump 3 2 operates at a higher rate mode: when 'observed feedback No. Vfb is higher than the reference voltage source~ too much, that is, the multi-mode charge 纟32 may have to enter a mode more than the current set to save unnecessary power consumption and improve the driving efficiency. The guest tongue is the same, < 夕重核式式泵泵32 is not limited to the structure shown in Figure 3 and three times 曰 Ψ ^ ^ ^ ^ ^ ^ 祆 而 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍Various magnifications ^ ^ ^ 杈式所, as long as it can use the pump capacitor charging / discharging technology to adjust the wheel 'electric anti-source Vin to the driving voltage v Out ° Figure 4 shows according to this hair - charge pump drive Details of 1340: - ^ ^ ^ ^ . : , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , In place of the single variable resistance unit VAR of the second embodiment, three variable resistor units VAR1, VAR2, and VAR3 separated from each other by 14 1294256 are used at the same time. Specifically, the first variable resistance unit VAR1 is connected in series with the switch. S1, the second variable resistance unit VAR2 is connected in series S3, and the third variable resistance unit VAR3 is connected in series to the switch S5. Like the single variable resistance unit VAR of the second embodiment, each of the variable resistance units VAR1, VAR3, and VAR5 of the third embodiment is also At the same time, it is controlled by the error signal Verr generated by the error amplifier 45. When the switch S1 is in the ON state, the first variable resistance unit VAR1 can adjust to flow into/out the first pump capacitor Cpl via the switch S1. When the switch S3 is in the ON state, the second variable resistor unit VAR2 can adjust the current flowing into/out of the second pump capacitor Cp2 via the switch S3. When the switch S5 is in the ON state, the third variable resistance unit VAR3 can adjust the current flowing into/out of the first or second pump capacitor Cpl or Cp2 via the switch S5. Fig. 5 is a detailed circuit diagram showing a charge pump driving circuit 50 for a light emitting diode according to a fourth embodiment of the present invention. The fourth embodiment is different from the third embodiment in that the fourth embodiment employs three P-type MOS transistors ST1, ST3, and ST5 in place of the switch S1 of the third embodiment and the variable resistor unit VAR1, respectively. S3 and variable resistance unit VAR2, and switch S5 and variable resistance unit VAR3. In addition to the simple switching characteristics of ON and OFF, the MOS transistor can control and adjust the current path between the drain and the source by the gate potential while operating in the ON state. Since the equivalent on-resistance Rds(()n) is equivalent, the MOS transistor can implement the circuit function of both the simple switch and the variable resistor unit. Therefore, the 15 1294256 P-type MOS transistors ST1, ST3, and ST5 are controlled to be turned "ON" and "OFF" by the switching control signals SCI and SC2 generated by the switching control circuit 53, but are generated by the error amplifier 55. The error signal Verr determines the equivalent on-resistance Rds(on) of its current source between the sources. Specifically, the source of the P-type MOS transistor ST1 is coupled to the input voltage source Vin, and the drain is coupled to the first electrode of the first pump capacitor Cpl and the switch S7. When the P-type MOS transistor ST1 is in an ON state, the error signal Verr generated by the error amplifier 55 passes through the gate of the P-type MOS transistor ST1 to adjust the current flowing through its current path. The source of the P-type MOS transistor ST3 is coupled to the first electrode of the second pump capacitor Cp2 and the switch S2, and the drain is coupled to the switch S6 and the driving voltage VQut. When the P-type MOS transistor ST3 is in an ON state, the error signal Verr generated by the error amplifier 55 passes through the gate of the P-type MOS transistor ST3 to adjust the current flowing through its current path. The source of the P-type MOS transistor ST5 is coupled to the second electrode of the second pump capacitor Cp2 and the switch S4, and the drain is coupled to the second electrode of the first pump capacitor Cpl and the switch S6. When the P-type MOS transistor ST5 is in an ON state, the error signal Verr generated by the error amplifier 55 passes through the gate of the P-type MOS transistor ST5 to adjust the current flowing through its current path. Although the present invention has been described by way of illustration of preferred embodiments, it is understood that the invention is not limited to the disclosed embodiments. On the contrary, the invention is intended to cover various modifications and modifications of the embodiments of the invention. Therefore, the scope of the patent application should be based on the broadest interpretation to accommodate all such modifications and similar configurations. 16 χ294256 [Simple diagram of the diagram] Figure 1U) Display Ub) Display waveform timing diagram. A detailed circuit diagram of a conventional charge pump driving circuit shows a switching control signal of a conventional charge pump driving circuit (#2), which is not used for a light-emitting diode according to the first embodiment of the present invention. Detailed circuit diagram of the pump drive circuit.

Fig. 3 shows a detailed circuit diagram of a package pump circuit for a light-emitting diode according to a second embodiment of the present invention. 4 is a detailed circuit diagram of a w=drive circuit for a light-emitting diode according to a third embodiment of the present invention. FIG. 5 shows a light-emitting diode according to a fourth embodiment of the present invention. Detailed circuit diagram of the electric pump circuit. Main component symbol description] 1 〇' 2〇,3〇4〇so ^ 11 12, 22, 13, 23, 14 24, 34, 15, 25, 16, 26, 37 , 47, 50 charge pump drive circuit load power switch control circuit 32, 42, 52 33, 43, 53 voltage detection circuit 44, 5 4 current adjustment circuit 35, 45, 55 error amplifier 36, 46, % filter 57 mode selection circuit 17 Ϊ294256

Cp, Cpl, Cp2 Pump Capacitor I〇ut Drive Current Iref Cangcao Current Source LED Light Emitting Diode MS Mode Select Signal OP Operational Amplifier Q1~ Q3 Transistor Rl, R2 Series Resistance SI~S 7 Switch SCI, SC2 Switching Control Signal ST1, ST3, ST5 P-type MOS transistor T1 to T2, T5 to T6 charging phase T3 to T4, T7 to T8 discharge phase VAR, VAR1 to VAR3 variable resistance unit Vin input voltage source V〇ut driving voltage vfb feedback signal Verr error signal Vref reference voltage source 18

Claims (1)

1294256 X. Patent application scope: 1. A charge pump driving circuit for driving a light emitting diode, comprising: a charge pump for converting an input electrical calendar source into a driving voltage for supplying to the light emitting diode a switching control circuit for controlling the charge pump to alternately operate in a charging phase and a discharging phase; a current regulating circuit having a current setting unit and a current regulating unit, wherein the current setting unit determines a reference current The current regulating unit has a current regulating end and a feedback detecting end, and the current regulating end is coupled to the light emitting diode to control a current flowing through the light emitting diode to be proportional to the reference current, the back The detection end provides a feedback signal representing a current regulation characteristic voltage; an error amplifier for generating an error signal based on a difference between the feedback signal and a reference voltage source; and a variable resistor The unit is configured to adjust a variable resistance value in response to the error signal between the input voltage source and the charge pump. 2. The charge pump drive circuit of claim 1, wherein: the charge pump has a first switch, a second switch, a third switch, a fourth switch, and a pump capacitor, the first opening a relationship between the input voltage source and a first electrode of the pump capacitor, the second open relationship being lightly coupled between the input voltage source and a second electrode of the pump capacitor, the third open relationship being coupled to the a second electrode of the pump capacitor and a ground potential, and the fourth open relationship is coupled between the first electrode of the pump capacitor and the driving power 19 Ϊ294256. 3. The charge fruit drive according to claim 2 a circuit, wherein: in the charging step 9, the switching control circuit causes the first and the third switch to be turned on, but the second and the fourth switches are not turned on, and the white slave is The switching control circuit causes the first switch and the third switch to be non-conducting, but the second switch and the fourth switch are both turned on. 4. The charge pump drive circuit of claim i, wherein: the charge pump has a first switch, a second switch, a third switch, a fourth switch, a fifth switch, and a sixth switch a seventh switch, and a first pump capacitor and a pump-gap, the first open relationship is coupled between the input voltage source and the first electrode of the first pump capacitor. The second open relationship is coupled between the wheeled voltage source and the first electrode of the second pump capacitor. The third open relationship is coupled to the first electrode of the second pump capacitor: the driving voltage The four-open relationship is lightly coupled to the input voltage (four) between the second electrode of the first pump capacitor, and the fifth open relationship is engaged with the second electrode and the second electrode and the second capacitor Between the two electrodes, the first open relationship is coupled between the second electrode of the first fruit capacitor and the driving voltage and the seventh open relationship is coupled between the first electrode of the first pump capacitor and a ground potential . 5 · If you apply for the fourth paragraph of the patent scope, Gong Yin; ^ + He pump drive circuit, in which: in the charging phase, the switch 饷 丨 + μ * ', the edge t knife change control circuit makes the first, The twentieth 20 1294256 three, the fourth, and the sixth switch are non-conducting, but the second, the fifth, and the seventh switch are both turned on, and in the discharging phase, the switching control circuit makes the The first, the third, the fourth, and the sixth switch are both turned on, but the second, the ith, and the seventh switch are not turned on. 6. The charge pump drive circuit of claim 4, i. In the charging phase, the switching control circuit causes the first, the second, the second, the third, and the sixth switch to be Turning on, but causing the fourth, the first, and the seventh switch to be both turned on, and in the discharging phase, the switching control circuit causes the second, the first, the fourth, the fifth, and the seventh None of the switches are electrically connected to the sixth switch. One time, "Hai Di 7. If you apply for a patent scope! The charge pump driving circuit of the item, the pot. The current setting unit has a reference electric first body, the reference current source provides the reference current, and the first electric body Γ source is coupled to a ground potential, And one of the body of the body, the current regulating unit has a second AND-operating amplifier, the second electric body: the body, the third transistor, the pw of the transistor, the electric system, the gate system Coupling to one of the gates of the first private day, the second node, the first pole is used as the current adjustment, one of the source lines is coupled to the ground potential, the - one of the electric dipoles is coupled to the inter-electrode of the body, the first: -" and one of the source of the first electro-optical body is coupled to the first electro-crystal 21 1294256 One of the operational amplifiers has a non-inverting input coupled to the drain of the second transistor, and an inverting input of the operational amplifier is coupled to the drain of the first transistor And as the feedback detection terminal, one of the output terminals of the operational amplifier is coupled to the first One of the gates of the three transistors. 8. The charge pump drive circuit of claim 3, wherein: the "Hai variable resistance unit is implemented by an equivalent on-resistance provided by a current channel of a transistor. 9. The charge pump drive circuit of claim 8, wherein: the current channel of the transistor is coupled between the input source and the pump, and one of the transistors The gate is controlled by the error signal. The pump driver circuit is used to drive the light-emitting diode, including: the electric pump is used to convert - the input voltage source becomes the - drive voltage, to the light The diode, the charge pump has a first switch, a second switch, a third switch, a fourth open, a fifth switch, a sixth switch, a seventh switch, and ~ ^ ^ _ Chu Ha brother a pump capacitor and a second pump electric valley, the child's open relationship is coupled to the wheel I_ + into the pressure source and the first pump electric valley between one of the electrodes, the second switch # Is coupled between the input voltage source and the first electrode of the second pump, and the ^ ^ ^ 二 二 开 合 合 合 合 该 该 该 该 该 该 该Between the coin r, the fourth open relationship is coupled between the wheeled voltage source and the second electrode of the second pump I11. 22 1294256 is lightly coupled to the _ _ ^ the second electrode of the second electrode and the second pump capacitor between ° % 垓 ' 垓 sixth open relationship coupled to the first pump capacitor 誃 two electrodes and the drive Between the voltages, and the seventh open relationship is coupled between the first electrode and a ground potential; a switching control circuit for controlling the charge pump to alternately charge the phase and a discharge phase; The circuit has a current setting unit and a current adjustment, the private/melon" and the unit determines a reference current, the current adjustment element has a package/; the IL adjustment end and a feedback detection end, the current adjustment Whether the motor is in the coiled light body to control the current flowing through the light emitting diode is proportional to the reference current, and the feedback detecting end provides a feedback signal, and the 苴 represents a current regulating characteristic voltage. And the error is amplified to generate an error signal based on the difference between the feedback signal and a reference voltage gate; a 曰-first variable resistor unit connected in series to the first switch for responding to the error Signal adjustment a variable resistance value; Μ: a second variable resistance unit connected in series to the third switch for adjusting a second variable resistance value in response to the error signal; and two t-th variable resistance units connected in series The fifth switch is configured to adjust the third variable resistance value in response to the 3 error number. 11. The charge pump drive circuit of claim 10, wherein: the first open relationship is implemented by a first transistor such that a current path of the first transistor is the first variable resistance unit; 23 l294256 曰 The second open relationship is implemented by a second transistor, such that the first crystal-current channel acts as the second variable resistance unit; and the fifth open relationship is performed by a third transistor It is implemented such that one current channel of the first crystal acts as the third variable resistance unit. I2. The charge pump drive circuit of claim U, wherein: the error signal is applied to one of the gates of the first transistor, and the current channel of the first transistor is buried The equivalent on-resistance is applied to one of the second transistors, and one of the current channels of the second transistor is equivalent to an equivalent on-resistance. The error signal is applied to the third transistor. One of the gates of the II three crystals; s:: Dad> _ ^ a efficacious power-on p and 13. The charge pump drive circuit of claim 10, in the charging phase The switching control circuit causes the first switch, the fourth switch, and the sixth switch to be non-conducting, but the =, the fifth, and the seventh switch are both turned on, and the first In the discharging phase, the switching control circuit causes the third, the fourth, and the sixth switch to be both turned on, but the first one, the first and the seventh switch are not turned on. W. The fifth, 14th, and the charge pump driving power according to item 10 of the patent application scope. In the charging phase, the switching control belt package 'in which: the third and the sixth switch are not conductive. The first value, the fourth value, the second 24th, the second switch, and the seventh switch are both turned on, and in the discharging phase, the switching control circuit 3, the fourth, the fifth, and the The seventh switch is both "-, the first and the sixth switch are both turned on. , 'but make the first I5 · as claimed in the scope of claim 10, the pumping circuit, the current setting unit has a reference source and a first lightning body, the reference current source provides the a reference current, the source of the power is coupled to a ground potential, and wherein the current adjustment unit has a second transistor, a third transistor, and an operational amplifier, the second transistor One of the gates of the M ^ ^ 日 day is coupled to the gate of the first body, and the first: the transistor of the transistor is used as the current mode, that is, the source of the second transistor. Coupling to the ground potential, one of the third transistors is coupled to the reference current source and the gate of the first transistor. The source of the second transistor is consumed by the first One of the crystals has a drain, and one of the operational amplifiers has a non-inverting input coupled to the drain of the first transistor, and an inverting input of the operational amplifier is coupled to the first transistor of the first transistor. Extremely and as the feedback detection end, one of the outputs of the differentiated amplification Is One crystal coupled to a third electrical gate. A charge pump driving method for providing a predetermined driving current to a light emitting diode, the light emitting diode having a first electrode and a second electrode, the method comprising: using a charge pump to convert An input voltage source becomes a driving voltage, and wherein the charge pump has at least one pump capacitor in 25 1294256, each of the at least one pump capacitor being coupled to the input voltage source and the driving voltage via a plurality of switches; supplying the driving And a voltage is applied to the first electrode of the light emitting diode; coupling a current adjusting circuit to the second electrode of the light emitting diode, so as to control a current flowing through the light emitting diode to be equal to the predetermined driving current; Detecting a current regulation characteristic voltage of the current adjustment circuit; and adjusting a variable resistor connected in series between the input voltage source and the at least one pump capacitor based on a difference between the current regulation characteristic voltage and a reference voltage source value. 1 7. The charge pump driving method according to claim 16 wherein: the current modulating circuit has a current setting early element and a current adjusting unit, wherein the current setting unit determines the predetermined driving current, The current adjustment unit has a current adjustment end coupled to the second detection electrode, and the current adjustment end is coupled to the second electrode of the LED, the feedback detection system provides the current regulation characteristic voltage . 1 8. The charge pump driving method of claim 16, wherein: the current regulating characteristic voltage represents a voltage of the current regulating terminal. 26