WO2016184169A1 - 多通道双模式数字控制led驱动电路及led灯 - Google Patents
多通道双模式数字控制led驱动电路及led灯 Download PDFInfo
- Publication number
- WO2016184169A1 WO2016184169A1 PCT/CN2016/073082 CN2016073082W WO2016184169A1 WO 2016184169 A1 WO2016184169 A1 WO 2016184169A1 CN 2016073082 W CN2016073082 W CN 2016073082W WO 2016184169 A1 WO2016184169 A1 WO 2016184169A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- output
- resistor string
- current
- mos transistor
- resistor
- Prior art date
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/24—Radio transmission systems, i.e. using radiation field for communication between two or more posts
- H04B7/26—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
- H04B7/2643—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using time-division multiple access [TDMA]
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/24—Radio transmission systems, i.e. using radiation field for communication between two or more posts
- H04B7/26—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
- H04B7/2643—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using time-division multiple access [TDMA]
- H04B7/2656—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using time-division multiple access [TDMA] for structure of frame, burst
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
- H05B41/14—Circuit arrangements
- H05B41/26—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
- H05B41/28—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
- H05B41/14—Circuit arrangements
- H05B41/26—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
- H05B41/28—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters
- H05B41/282—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
- H05B41/14—Circuit arrangements
- H05B41/36—Controlling
- H05B41/38—Controlling the intensity of light
- H05B41/39—Controlling the intensity of light continuously
- H05B41/392—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
- H05B41/14—Circuit arrangements
- H05B41/36—Controlling
- H05B41/38—Controlling the intensity of light
- H05B41/39—Controlling the intensity of light continuously
- H05B41/392—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor
- H05B41/3921—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor with possibility of light intensity variations
- H05B41/3927—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor with possibility of light intensity variations by pulse width modulation
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/40—Details of LED load circuits
- H05B45/44—Details of LED load circuits with an active control inside an LED matrix
- H05B45/46—Details of LED load circuits with an active control inside an LED matrix having LEDs disposed in parallel lines
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B47/00—Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
- H05B47/10—Controlling the light source
- H05B47/165—Controlling the light source following a pre-assigned programmed sequence; Logic control [LC]
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B47/00—Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
- H05B47/10—Controlling the light source
- H05B47/17—Operational modes, e.g. switching from manual to automatic mode or prohibiting specific operations
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
- Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection
Definitions
- the invention relates to the field of LEDs, in particular to a multi-channel dual-mode digital control LED driving circuit and an LED lamp.
- LEDs have received increasing attention in the field of lighting due to their high efficiency, low consumption, environmental protection, small size and long life. Limited by its optical and electrical characteristics, LEDs must be supplemented with dedicated constant current drive circuits to work properly, so the importance of LED drive systems is self-evident.
- the analog mode is usually analog, that is, the process of changing the output voltage by controlling the duty cycle change by comparing the sampled signal with a fixed voltage.
- the main disadvantages of this kind of invention are as follows: First, the working mode is single, the system stability is general, from the current sampling to the feedback control, the system needs to be completely adjusted, and the response speed is slow. Second, the control circuit is mostly a simple comparison process, and the precision is relatively low. The output voltage range is too large after feedback, and the accuracy of the control part is also reduced due to environmental factors such as process deviation, temperature, humidity, etc. Third, the versatility of the system is poor, and usually the drive system is more dedicated, practical application. It is difficult to achieve the change of conditional application, increase and decrease function, etc.
- the object of the present invention is to provide a multi-channel dual-mode digital control LED driving circuit and an LED lamp, which are fed back through a digital control module to adjust the voltage of the load, and the constant current control module feedbacks the load in real time.
- Current, dual mode operation with a wide range of versatility.
- a multi-channel dual-mode digital control LED driving circuit comprises: a current sampling module, a comparison detection module, a digital control module and a constant current control module;
- the current sampling module converts the current signal of the load into a sampling voltage signal, and outputs the signal to the comparison detection module and the constant current control module; the comparison detection module compares the sampling voltage with a fixed voltage, and generates a high and low level signal according to the comparison result.
- the digital control module Outputting to the digital control module, simultaneously generating a dynamically changing voltage signal output to the constant current control module; the digital control module sequentially giving the external rise according to the high and low level signals output by the comparison detection module, corresponding to the output signal of the output rising or falling
- the pressure control module and the driving module realize feedback adjustment of the load;
- the constant current control module compares the sawtooth wave signal of the fixed frequency according to the sampling voltage, generates a switching signal with a duty cycle change in real time, and uses the switching signal duty cycle change control Its internal constant current drive tube switch state, real-time feedback to adjust the load current.
- the comparison detecting module includes:
- the detecting unit is configured to compare and amplify the sampling voltage and the fixed voltage, and output the amplified signal to the comparing unit, and the larger the ratio of the fixed voltage to the sampling voltage is, the larger the voltage of the amplified signal is output;
- a comparing unit configured to: when the amplified signal output by the detecting unit is greater than the first threshold voltage, the first output terminal outputs a low level, and the second output terminal outputs a high level, when the amplified signal output by the detecting unit is less than the second threshold voltage The first output end outputs a high level, and the second output end outputs a low level.
- the amplified signal outputted by the detecting unit is greater than the second threshold voltage and smaller than the first threshold voltage, the first output end and the second output end output Low level
- the input end of the detecting unit is connected to the output end of the current sampling module, the detecting unit is connected to the comparing unit, and the first output end and the second output end of the comparing unit are connected to the digital control module.
- the digital control module includes:
- a logic unit for converting the signals of the two output ends of the comparison unit into an eight-bit logic control signal.
- the eight-bit logic control signal is Low to high rises bit by bit in the 256-bit interval; when the first output of the comparison unit outputs a high level and the second output outputs a low level, the eight-bit logic control signal is bit by bit in the 256-bit interval from high to low. Decrease; when the first output of the comparison unit outputs a low level and the second output outputs a low level, the eight-bit logic control signal remains unchanged;
- the voltage control unit is configured to reduce the output voltage by one step voltage every time the eight-bit logic control signal rises by one bit, and increase the output voltage by one step voltage every time the eight-bit logic control signal is decreased by one bit;
- the first input end of the logic unit is connected to the first output end of the comparison unit, and the second input end of the logic unit is connected to the second output end of the comparison unit, and the logic unit passes
- the voltage control unit is connected to an external boost control module.
- the voltage control unit includes a first current switching subunit, a second current switching subunit, and a third current switching subunit controlled by an eight-bit logic control signal. a four current switch subunit, a fifth current switch subunit, a sixth current switch subunit, a seventh current switch subunit, an eighth current switch subunit, a resistor array connected by a binary rule, and a mirror current subunit;
- the resistor array includes a first resistor string, a second resistor string, a third resistor string, a fourth resistor string, a fifth resistor string, a sixth resistor string, a seventh resistor string, an eighth resistor string, and a ninth resistor string.
- the current switch subunit is configured to output a first mirror current to the resistor array according to a corresponding logic control signal of the eight-bit logic control signal;
- the mirror current subunit is configured to output a second mirror current to the resistor array
- the external power supply terminal is connected to one end of the first resistor string and one end of the ninth resistor string through the first current switch subunit, the other end of the first resistor string is grounded; the external power supply terminal is connected to the ninth resistor through the second current switch subunit The other end of the string, one end of the second resistor string and one end of the tenth resistor string, the other end of the second resistor string is grounded; the external power supply terminal is connected to the other end of the tenth resistor string through the third current switch subunit, One end of the three resistor string and one end of the eleventh resistor string, the other end of the third resistor string is grounded; the external power supply terminal is connected to the other end of the eleventh resistor string and the fourth resistor string through the fourth current switch subunit One end and one end of the twelfth resistor string, the other end of the fourth resistor string is grounded; the external power supply terminal is connected to the other end of the twelfth resistor string and the fifth resistor string through the fifth current switch subunit
- the current sampling module includes a first resistor, a second resistor, a first MOS transistor, and a second MOS transistor; one end of the first resistor is connected to a load, The other end of the first resistor is connected to the drain of the first MOS transistor, the source of the first MOS transistor is connected to the drain of the second MOS transistor through a second resistor, and the drain of the second MOS transistor is a current sampling module At the output end, the gate and the source of the second MOS transistor are grounded.
- the detecting unit includes a first operational amplifier, a first capacitor, a second capacitor, a third capacitor, a third resistor, a fourth resistor, a third MOS transistor, and a a fourth MOS transistor, a fifth MOS transistor, and a sixth MOS transistor; an inverting input end of the first operational amplifier is an input end of the detecting unit, a drain connected to the second MOS transistor, and a positive phase of the first operational amplifier The input end is connected to the fixed voltage supply end, and the output end of the first operational amplifier is connected to one end of the first capacitor, the drain of the third MOS transistor, one end of the second capacitor, and the gate of the fourth MOS transistor, the first Electricity The other end of the capacitor is connected to the source of the third MOS transistor, the drain of the fifth MOS transistor, the other end of the second capacitor, the source of the fourth MOS transistor, and the drain of the sixth MOS transistor through the third resistor.
- a gate of the third MOS transistor is connected to an enable signal, a drain of the fifth MOS transistor is further connected to an inverting input terminal of the first operational amplifier, and a source of the fifth MOS transistor is connected to a positive phase of the first operational amplifier
- the input terminal is also grounded through a third capacitor, the gate of the fifth MOS transistor is connected to the PWM inversion signal supply terminal; the drain of the fourth MOS transistor is connected to the external power supply terminal through the fourth resistor, the fourth MOS
- the source of the tube is the output of the detection unit, the input of the connection comparison unit, and the constant current control module; the source of the sixth MOS tube is grounded.
- the comparison unit includes a first comparator, a second comparator, a first buffer, and a second buffer; a positive phase input terminal of the first comparator Connecting a first threshold voltage supply terminal, the inverting input terminal of the first comparator and the non-inverting input terminal of the second comparator are connected to the source of the fourth MOS transistor, and the inverting input terminal of the second comparator is connected a second threshold voltage supply terminal; an output end of the first comparator is connected to an input end of the first buffer, an output end of the first buffer is a first output end of the comparison unit, and the second comparator is The output is connected to the input of the second buffer, and the output of the second buffer is the second output of the comparison unit.
- each current switch subunit includes two PMOS tubes and one switch tube; the two PMOS tubes are cascodes Bias current Source structure: the source of one PMOS tube is connected to the external power supply terminal, the drain is connected to the source of another PMOS tube, and the drain of the other PMOS tube is connected to the source of the switch tube; the gate of the switch tube is connected to the output of the logic unit The drain of the switch is the output of the current switch subunit and is grounded through the resistor string.
- the constant current control module includes a third comparator and a second operational amplifier, and a non-inverting input terminal of the third comparator is connected to an output end of the detecting unit,
- the inverting input terminal of the third comparator is connected to the low frequency sawtooth signal providing end inherent in the LED driving system, and the output end of the third comparator is connected to the negative power terminal of the second operational amplifier, and the power supply of the second operational amplifier is positive
- the terminal is connected to the external power supply terminal VCC; the forward input terminal of the second operational amplifier is connected to the high voltage signal supply terminal, and the reverse input terminal of the second operational amplifier is connected to the output terminal of the sampling module, the second operational amplifier The output is connected to the load.
- An LED lamp comprising a multi-channel dual mode digitally controlled LED drive circuit as described above.
- the multi-channel dual-mode digital control LED driving circuit and the LED lamp provided by the invention feed back and adjust the voltage of the load through the digital control module, and the constant current control module feedbacks the current of the load in real time, and performs the load change in real time.
- the adjustment realizes the dual mode cooperation work, greatly improves the response speed, improves the accuracy of the output voltage and the load current, and at the same time enhances the stability of the system and has wide versatility.
- FIG. 1 is a structural block diagram of a multi-channel dual-mode digitally controlled LED driving circuit provided by the present invention
- FIG. 2 is a circuit diagram of a current sampling module and a comparison detection module in a multi-channel dual-mode digital control LED driving circuit provided by the present invention
- FIG. 3 is a circuit diagram of a logic unit in a multi-channel dual-mode digitally controlled LED driving circuit provided by the present invention
- FIG. 4 is a circuit diagram of a voltage control unit in a multi-channel dual-mode digitally controlled LED driving circuit provided by the present invention
- FIG. 5 is a circuit diagram of a constant current control module in a multi-channel dual-mode digitally controlled LED driving circuit provided by the present invention
- FIG. 6 is a circuit diagram of an LED constant current driving system using a multi-channel dual mode digitally controlled LED driving circuit provided by the present invention.
- the invention provides a multi-channel dual-mode digital control LED driving circuit and an LED lamp, and realizes dual mode matching work through a digital control module and a constant current control module, thereby improving the accuracy of the output voltage and the load current.
- the multi-channel dual-mode digital control LED driving circuit comprises: a current sampling module 10, a comparison detecting module 30, a digital control module 40, and a constant current control module 20.
- the current sampling module 10 converts the current signal of the load 70 into a sampling voltage signal, and outputs the same to the comparison detecting module 30 and the constant current control module 40; the comparison detecting module 30 Comparing the sampling voltage with the fixed voltage, generating a high-low level signal according to the comparison result, outputting to the digital control module 40, and simultaneously generating a dynamically changing voltage signal to the constant current control module 20; the digital control module 40 is based on the comparison detection module
- the output high-low level signal of 30 outputs the output signal corresponding to the output rising or falling to the external boost control module 50 and the driving module 60 to realize feedback adjustment of the load; the constant current control module 20 compares and fixes according to the sampling voltage.
- the frequency sawtooth signal generates a switching signal with a duty cycle change in real time, and controls the switching state of the internal constant current driving tube by using the switching signal duty cycle change, thereby real-time feedback adjusting the current of the load.
- the external boost control module 50 is configured to perform boost control on the signal output by the digital control module 40 and control the drive module 60 to drive and adjust the load 70.
- the multi-channel dual-mode digital control LED driving circuit provided by the invention feeds back the voltage of the load through the digital control module, and the constant current control module feedbacks the current of the load in real time, and adjusts the load change in real time to realize the dual mode cooperation.
- the work greatly improves the response speed, improves the accuracy of the output voltage and the load current, and at the same time enhances the stability of the system and has wide versatility.
- the current sampling module 10 includes a first resistor R1, a second resistor R2, a first MOS transistor Q1, and a second MOS transistor Q2.
- One end of the first resistor R1 is connected to the load 70.
- the other end of the first resistor R1 is connected to the drain of the first MOS transistor Q1, and the source of the first MOS transistor Q1 is connected to the drain of the second MOS transistor Q2 through the second resistor R2.
- the second MOS transistor Q2 The drain is the output of the current sampling module 10, the output sampling voltage VN, and the gate and source of the second MOS transistor Q2 are grounded.
- the first MOS transistor Q1 and the second MOS transistor Q2 are NMOS transistors.
- the first The gate of a MOS transistor Q1 is connected to the PWM signal supply terminal to receive the PWM signal. When no dimming is required, the gate of the first MOS transistor Q1 receives a high level signal to make the first MOS transistor Q1 in a normally-on state.
- the current sampling module 10 is a balanced sampling structure, which can effectively save PCB area.
- the second resistor R2 and the first resistor R1 have a large ratio structure, and the ratio is determined according to the external sampling current.
- the external current is in the milliamperes (mA) to hundreds of milliamps (mA) stages, and the first resistor R1 and the second resistor are used.
- the current of R2 is generally in the microampere (uA) stage, so the ratio of the resistance of the second resistor R2 to the first resistor R1 is between several K:1 and several hundred K:1, and preferably, the ratio is 10000:1.
- the first MOS transistor Q1 is a PWM signal switching tube, and the LED driving system can add a PWM dimming function as needed, and the PWM signal is input from the gate of the first MOS transistor Q1, if the gate signal of the first MOS transistor Q1 is set to be high.
- the level is equivalent to canceling the PWM dimming function, that is, the LED can be dimmed by the first MOS transistor Q1.
- the comparison detecting module 30 includes a detecting unit 310 and a comparing unit 320.
- the detecting unit 310 is configured to compare and amplify the sampling voltage VN and the fixed voltage VP, and output the amplified signal to the comparing unit 320.
- the multi-channel dual-mode digital control LED driving circuit provided by the invention can realize the function of analog dimming by adjusting the size of the fixed voltage VP, that is, adjusting the size of the fixed voltage VP, and controlling the range of the load current value to realize the simulation. Dimming.
- the comparison unit 320 is configured to: the amplified signal Vo outputted by the detecting unit 310 is greater than the first When the threshold voltage is VL, the first output terminal outputs a low level, and the second output terminal outputs a high level.
- the amplified signal Vo outputted by the detecting unit 310 is smaller than the second threshold voltage VH, the first output terminal outputs a high level, The second output terminal outputs a low level.
- the amplified signal Vo outputted by the detecting unit 310 is greater than the second threshold voltage VH and smaller than the first threshold voltage VL, the first output terminal and the second output terminal output a low level.
- the comparison unit 320 is configured to: the amplified signal Vo outputted by the detecting unit 310 is greater than the first When the threshold voltage is VL, the first output terminal outputs a low level, and the second output terminal outputs a high level.
- the input end of the detecting unit 310 is connected to the output end of the current sampling module 10, and the detecting unit 310 is connected to the comparing unit 320.
- the first output end 1 and the second output end 2 of the comparing unit 320 are connected to the digital control module 40.
- the detecting unit 310 includes a first operational amplifier U1, a first capacitor C1, a second capacitor C2, a third capacitor C3, a third resistor R3, a fourth resistor R4, a third MOS transistor Q3, and a fourth MOS transistor.
- an inverting input terminal of the first operational amplifier U1 is an input end of the detecting unit 310, and a drain connected to the second MOS transistor Q2, the first operational amplifier
- the non-inverting input terminal of the U1 is connected to the fixed voltage supply terminal, and the output terminal of the first operational amplifier U1 is connected to one end of the first capacitor C1, the drain of the third MOS transistor Q3, one end of the second capacitor C2, and the fourth MOS transistor.
- the gate of Q4, the other end of the first capacitor C1 is connected to the source of the third MOS transistor Q3, the drain of the fifth MOS transistor Q5, the other end of the second capacitor C2, and the fourth MOS transistor through the third resistor R3.
- the source of Q4 and the drain of the sixth MOS transistor Q6, the gate of the third MOS transistor Q3 is connected to the enable signal EN, and the drain of the fifth MOS transistor Q5 is also connected to the inversion of the first operational amplifier U1.
- the input terminal, the source of the fifth MOS transistor Q5 is connected to the non-inverting input terminal of the first operational amplifier U1, and is also grounded through the third capacitor C3.
- a gate of the fifth MOS transistor Q5 is connected to the PWM inversion signal supply terminal; the fourth The drain of the MOS transistor Q4 is connected to the external power supply terminal VCC through the fourth resistor R4.
- the source of the fourth MOS transistor Q4 is the output terminal of the detecting unit 310, the input terminal of the connection comparing unit 320, and the constant current control module 20;
- the source of the sixth MOS transistor Q6 is grounded.
- the third MOS transistor Q3, the fourth MOS transistor Q4, the fifth MOS transistor Q5, and the sixth MOS transistor Q6 are NMOS transistors.
- the fixed voltage VP is set by the LED driving system. When no dimming is required, it can be provided by a low-dropout linear regulator in the system. Of course, when dimming is required, only the fixed voltage VP can be changed.
- the first operational amplifier U1, the fourth resistor R4, the fourth MOS transistor Q4, and the sixth MOS transistor Q6 form a two-stage operational amplifier structure.
- the first operational amplifier U1 is the first stage of the two-stage operational amplifier; the fourth resistor R4, the fourth MOS transistor Q4, and the sixth MOS transistor Q6 serve as the second stage of the two-stage operational amplifier.
- the first capacitor C1, the second capacitor C2 and the third resistor R3 are both Miller compensations of the two-stage operational amplifier.
- the benefit of adding compensation is that the performance is more stable when the vehicle is operated at a high frequency.
- the gate input of the fifth MOS transistor Q5 is the inverted signal PWM_inv of the PWM signal, and the drain and the source of the fifth MOS transistor Q5 are respectively connected to the non-inverting input terminal and the inverting input terminal of the first operational amplifier U1, due to the circuit pre-
- the PWM dimming function is left, so the role here is that when the PWM dimming signal is turned off, the fifth MOS transistor Q5 is turned on, forcing the fixed voltage VP to be close to the sampling voltage VN, preventing the PWM signal from rapidly switching to the output signal to cause signal disturbance.
- the output of the two-stage operational amplifier is the fourth MOS transistor Q4, and the second stage is the source follower structure. Therefore, the output signal Vo is a voltage signal, and the voltage magnitude is determined according to the magnitude of the fixed voltage VP/sampling voltage VN.
- the comparing unit 320 includes a first comparator U2, a second comparator U3, a first buffer U4 and a second buffer U5; the first phase input terminal of the first comparator U2 is connected to the first a threshold voltage supply terminal, the inverting input terminal of the first comparator U2 and the non-inverting input terminal of the second comparator U3 are connected to the source of the fourth MOS transistor Q4, and the inverting input of the second comparator U3 The terminal is connected to the second threshold voltage supply terminal; the output terminal of the first comparator U2 is connected to the input end of the first buffer U4, and the output terminal of the first buffer U4 is the first output terminal 1 of the comparison unit 320.
- the digital control module 40 is connected, the output end of the second comparator U3 is connected to the input end of the second buffer U5, and the output end of the second buffer U5 is the second output end 2 of the comparison unit 320. Module 40.
- the signals that have been compared by the first comparator U2 and the second comparator U3 are respectively buffered by a first stage and then logically combined to generate a high-low level signal, which is output to the digital control module 40. Since the output signal Vo of the detecting unit 310 is a voltage signal, the second threshold voltage VH is set, the first threshold voltage VL is a high and low window threshold voltage (VH>VL), and when the fixed voltage VP>the sampling voltage VN, the output voltage Vo> The second threshold voltage VH, so that the first output terminal 1 of the comparison unit 320 outputs a low level, and the second output terminal 2 outputs a high level.
- the first output terminal 1 of the comparison unit 320 When the fixed voltage VP ⁇ the sampling voltage VN, the output voltage Vo ⁇ the first threshold voltage VL, the first output terminal 1 of the comparison unit 320 outputs a high level, and the second output terminal 2 outputs a low level. If VP is close to or equal to VN, according to the common mode analysis, VL ⁇ Vo ⁇ VH at this time, the first output terminal 1 and the second output terminal 2 of the comparison unit 320 both output a low level. It can be seen that the output of the first output terminal 1 and the second output terminal 2 of the comparison unit 320 is determined by the relationship between VP and VN, and the signals output by the first output terminal 1 and the second output terminal 2 simultaneously serve as a digital control module. 40 control source signal. The relationship between the signal outputted by the first output terminal 1 and the second output terminal 2 of the comparison unit 320 and VP/VN can be summarized as follows:
- the digital control module 40 includes:
- the logic unit 410 is configured to convert the signals of the two output ends of the comparison unit 320 into an eight-bit logic control signal.
- eight The bit logic control signal rises bit by bit in the 256-bit interval from low to high; when the first output terminal 1 of the comparison unit 320 outputs a high level and the second output terminal 2 outputs a low level, the eight-bit logic control signal goes from high to high.
- the low bit is dropped bit by bit in the 256-bit interval; when the first output terminal 1 of the comparing unit 320 outputs a low level and the second output terminal 2 outputs a low level, the eight-bit logic control signal remains unchanged.
- the logic unit 410 includes eight output terminals, and the eight signals outputted by the signals are Z1 to Z8, and each output terminal outputs a high level or a low level, that is, a signal Z1 of the output terminals of the logic unit 410.
- Z8 constitutes an eight-bit logic control signal.
- the eight-bit logic control signal is represented by binary and can be composed of 256 different binary numbers.
- the logic unit 410 includes eight logic subunits LOGIC, and the function of the logic subunit LOGIC is to logically synthesize the signals input by the two input ends of the logic unit 410, and integrate the input signals into corresponding eight-bit logic control signals. Its internal structure is composed of digital units such as D flip-flops and RS latches.
- the voltage control unit is configured to reduce the output voltage by one step voltage Vstep every time the eight-bit logic control signal rises by one bit, and increase the output voltage by a step voltage Vstep every time the eight-bit logic control signal falls by one bit.
- the first input 1' of the logic unit 410 is connected to the first output 1 of the comparison unit 320, and the second input 2' of the logic unit 410 is connected to the second input of the comparison unit 320.
- the logic unit 410 is connected to the external boost control module through a voltage control unit.
- the voltage of the load 70 can be adjusted, and the range of the adjustment is divided into 256 sections, so that the adjustment of the load 70 is performed. Become extremely precise and smooth.
- the voltage control unit includes a first current switch subunit 421, a second current switch subunit 422, a third current switch subunit 423, and a fourth current switch subunit 424 controlled by an eight-bit logic control signal.
- the resistor array includes a first resistor string 430, a second resistor string 431, a third resistor string 432, a fourth resistor string 433, a fifth resistor string 434, a sixth resistor string 435, a seventh resistor string 436, and an eighth resistor.
- the current switch subunit is configured to output a first mirror current I1 to the resistor array according to a corresponding logic control signal in the eight-bit logic control signal.
- the mirror current sub-unit 429 is configured to output a second mirror current I2 to the resistor array.
- the external power supply terminal VCC is connected to one end of the first resistor string 430 and one end of the ninth resistor string 438 through the first current switch sub-unit 421, the other end of the first resistor string 430 is grounded; the external power supply terminal VCC passes the second current switch
- the sub-unit 422 is connected to the other end of the ninth resistor string 438, one end of the second resistor string 431, and one end of the tenth resistor string 439.
- the other end of the second resistor string 431 is grounded; the external power supply terminal VCC passes the third current.
- the switch subunit 423 is connected to the other end of the tenth resistor string 439, one end of the third resistor string 432, and one end of the eleventh resistor string 440.
- the other end of the third resistor string 432 is grounded; the external power supply terminal VCC passes the fourth The current switch subunit 424 is connected to the other end of the eleventh resistor string 440, one end of the fourth resistor string 433, and one end of the twelfth resistor string 441.
- the other end of the fourth resistor string 433 is grounded; the external power supply terminal VCC passes The fifth current switch subunit 425 is connected to the other end of the twelfth resistor string 441, one end of the fifth resistor string 434, and one end of the thirteenth resistor string 442.
- the other end of the fifth resistor string 434 is grounded;
- the external power supply terminal VCC is connected to the other end of the thirteenth resistor string 442, one end of the sixth resistor string 435, and one end of the fourteenth resistor string 443 through the sixth current switch subunit 426, and the other end of the sixth resistor string 435 is grounded;
- the power supply terminal VCC is connected to the other end of the fourteenth resistor string 443, one end of the seventh resistor string 436, and one end of the fifteenth resistor string 444 through the seventh current switch subunit 427, and the other end of the seventh resistor string 436 is grounded.
- the eighth current switch subunit 428 and the mirror current subunit 429 are connected to the other end of the fifteenth resistor string 444 and one end of the eighth resistor string 437, and the other end of the eighth resistor string 437 is grounded; the eighth resistor One end of the string 437 is the output of the voltage control unit and is connected to the external boost control module 50.
- the seventh current switch subunit 427 and the eighth current switch subunit 428 are all the same and are coupled to the first resistor string 430, the second resistor string 431, the third resistor string 432, the fourth resistor string 433, and the fifth resistor string 434.
- each current switch subunit includes Two PMOS tubes and one switch tube; two PMOS tubes are cascode bias current source structures, one PMOS tube has a source connected to an external supply terminal, a drain connected to another PMOS tube source, and another PMOS tube The drain is connected to the source of the switch tube, and the gate of the switch tube is connected to the output end of the logic unit. The drain of the switch tube is the output end of the current switch subunit, and is grounded through the corresponding resistor string.
- the gates of the switching transistors in the eight current switching subunits are connected to one of the eight output terminals of the logic unit 410, that is, the eight-bit logic control signal controls the on and off of the eight current switching subunits, thereby changing the voltage control unit. Output voltage.
- the mirror current subunit 429 includes a seventh MOS transistor Q7 and an eighth MOS transistor Q8.
- the seventh MOS transistor Q7 and the eighth MOS transistor Q8 are PMOS transistors and are in a normally-on state.
- the resistance of the resistor array is the same, wherein the first resistor string 430, the ninth resistor string 438, the tenth resistor string 439, the eleventh resistor string 440, the twelfth resistor string 441, and the thirteenth resistor string 442,
- the fourteenth resistor string 443 and the fifteenth resistor string 444 include two resistors connected in series, a second resistor string 431, a third resistor string 432, a fourth resistor string 433, a fifth resistor string 434, and a sixth resistor string 435.
- the seventh resistor string 436 and the eighth resistor string 437 include four resistors in series.
- the eight-bit logic control signal is generated by the logic unit 410.
- the output signals of the first output terminal 1 and the second output terminal 2 of the comparison unit 320 can control the logic unit 410 to generate the state of the eight-bit logic control signal, thereby controlling the output of the digital control module 40.
- the rise and fall of voltage VREF, and this process is reversible in real time.
- the current switch subunit and its corresponding resistor string form a single channel path, wherein
- the two PMOS transistors of the flow switch subunit are cascode bias current source structures, the main function is to mirror the external current as the current I1 of the channel, and the switch tube can be based on one of the corresponding eight-bit logic control signals. High or low to determine whether to conduct.
- the mirror current sub-unit 429 is a normally-on path, and the current of the mirror image is I2, and the ratio of the width to length ratio of the second MOS transistor Q7/eighth MOS transistor Q8 and the two PMOS transistors in the current switch sub-unit can be set. To set the size of the I2 current.
- the digital control module 40 output voltage VREF can be calculated by multiplying the mirror current I2 by the total resistance of the resistor array. Taking the Y1 and Y2 branches controlled by the eighth current switch subunit 428 in FIG. 4 as an example, the voltage of the Y1 branch is The voltage of the Y2 branch is among them Is the voltage value on the seventh resistor string, and It is the voltage value on the fifteenth resistor string.
- the voltages of the branches controlled by the other seven current switch subunits can be obtained, that is, the output voltage of the digital control module 40 is Since the eight current switch subunits are all disconnected, there is no first mirror current I1, so the current on all the resistors is provided by the second mirror current I2, at which time VREF is at least Vmin.
- the eight-bit logic control signal (Z1-Z8) appears as a high-low level signal according to the eight-bit binary rule
- the current switch sub-unit is turned on, the first mirror current I1 is superimposed on the corresponding channel according to the corresponding binary rule.
- the current on the resistor on this channel increases, so VREF will also increase.
- VREF is one step in Vstep.
- Vstep is determined by the absolute value of the first mirror current I1 and the resistor R in the resistor array.
- the first mirror current I1 and the resistor R in the resistor array The larger the absolute value, the larger the Vstep, and the smaller the reverse, the more you can set it according to the specific application.
- Z1-Z8 are all low level, the eight current switch subunits are turned on, and the first mirror current I1 of the eight channels are superimposed, and VREF is at most Vmax.
- the range of VREF is determined by three factors: the first mirror current I1, the second mirror current I2, and the resistor R in the resistor array. In practical applications, adjustment can be made as needed.
- the upper principle analysis shows that the eight-bit logic control signal controls the superposition of the first mirror current I1, thereby affecting the VREF variation.
- the width and length ratios of the PMOS transistors of the eight current switch subunits are all designed to be equal, so the first mirror current I1 on each channel tends to be uniform, and all the resistors R are designed in equal proportions, and all the PMOS transistors and the resistor R are strictly matched.
- the purpose is to make the change trend of each channel the same.
- the advantage of this technology is that it can greatly reduce the influence of process deviation, temperature, humidity and stress.
- control mode of the digital control module 40 is different from the traditional analog control mode, and the voltage control is accurate, and the amplitude and the lifting range of the adjusted step voltage can be freely set (according to the absolute values of I1 and R). Size setting), can effectively increase the control voltage The accuracy of the output reduces ripple.
- This part of the control mode uses the current switch to control the voltage divider value of the resistor. Because the resistors are strictly matched and the current mirror tube size of each channel is strictly matched, the effects of process variation, temperature, humidity and other factors in production can be greatly reduced.
- the constant current control module 20 includes a third comparator U6 and a second operational amplifier U7.
- the positive phase input terminal of the third comparator U6 is connected to the output end of the detecting unit 310, and the third comparator U6.
- the inverting input terminal is connected to the low frequency sawtooth signal Vramp providing end inherent in the LED driving system, and the output end of the third comparator U6 is connected to the power negative terminal of the second operational amplifier U7, and the power supply of the second operational amplifier U7
- the positive terminal is connected to the external power supply terminal VCC; the forward input terminal of the second operational amplifier U7 is connected to the high voltage signal supply terminal (input 5V, 4V, etc.), and the reverse input terminal of the second operational amplifier U7 is connected to the sampling module.
- the output of the second operational amplifier U7 is coupled to the load 70.
- the third comparator U6 compares the sampling voltage Vo with the low frequency sawtooth signal Vramp inherent in the system, and generates a square wave output signal with an adjustable duty ratio, wherein the duty ratio is determined by the voltage level of Vo.
- the signal outputted by the third comparator U6 controls the second operational amplifier U7.
- the operating state of the second operational amplifier U7 is designed to be in an all-pass state, that is, the input of the non-inverting input of the second operational amplifier U7 is a high voltage signal (for example, 5V, 4V).
- the inverting input terminal inputs the sampling voltage signal VN, wherein the sampling voltage signal VN is generally much smaller than the high voltage signal, so the signal Vled outputted by the output terminal of the second operational amplifier U7 is always in a high state, constant current control
- the module 20 controls the output signal Vled through the square wave signal with adjustable duty ratio generated by the third comparator U6, thereby controlling the duty ratio of the Vled, and using the change of the duty ratio to realize the change of the average value of the output current to achieve the control of the load current. purpose.
- the constant current control module 20 directly compares the sampled voltage signal with the sawtooth wave and directly feeds back to the load current to participate in the adjustment, which is essentially a feedforward loop in the system. This mode of operation is one of the dual modes, because After the system loop feedback, the response speed of the system is greatly improved.
- the multi-channel dual-mode digitally controlled LED driving circuit provided by the present invention has the following beneficial effects:
- the invention adopts dual mode control, the whole large loop feedback adopts the peak current mode operation, and the small loop constant current control part adds the feedforward control to adjust the load current duty ratio in real time, and adjusts the load change in real time, which greatly improves. responding speed;
- the invention realizes an eight-bit digital control system to adjust the output voltage, improve the output voltage precision, reduce the ripple, and the unique current control circuit can effectively reduce the influence of process deviation, temperature and other factors on the system;
- the circuit of the invention reserves the adjustable function, the number of channels, the PWM dimming function, the digital adjustment step voltage, the digital control part window voltage, etc., and the actual application can be set according to requirements, enriching the application flexibility. .
- the peripheral power drive tube Q, the inductor L1, the freewheeling diode D1, and the charging capacitor C1 form a classic boost structure.
- the load of the system is n string LED strips (the dotted line indicates the omitted LED light emitting diode), the NMOS tube NM51/NM52... ...NM5n is the drive tube of n string LED strips, R1'/R2'...Rn' are the corresponding n sampling resistors.
- Isen1 is the load current sampling signal, which samples the load current in real time.
- This signal is input to the current sampling module.
- the large loop works as follows: the sampling signal passes through the comparison detection module and outputs a digital control signal, which determines the voltage rise and fall in the digital control module, and then passes through the external boost control module and the drive module.
- the sampled current signal change is reflected by the duty cycle of the square wave signal from the drive module to the drive tube.
- the output voltage VOUT can be changed at any time. When Isen1 does not reach the set value, VOUT continues to rise. When the system is stable, VOUT is in dynamic equilibrium.
- the small loop works as follows:
- the load current sampling signal is transmitted to the constant current control module, and compared with the sawtooth signal of the fixed frequency inside the system, the change of the current signal causes a change in the output duty ratio, and the modulated signal is fed back to the signal.
- the gates K1/K2...Zn of the drive tube act as feedforward, which improves the response speed of the system.
- the dotted frame portion is a multi-channel dual-mode digital control LED driving circuit provided by the present invention
- the peripheral circuit can increase or decrease the number of channels according to actual applications, and additionally adjust the precision of PWM dimming, analog dimming, and digital control module. Indicators can also be increased or decreased according to demand, and the scope of application is wide.
- the multi-channel dual-mode digitally controlled LED driving circuit provided by the invention is also applicable to any LED-driven electronic system and constant current driving system.
- the invention also provides an LED lamp comprising the multi-channel dual mode digitally controlled LED drive circuit as described above. Since the working principle and technical features of the LED lamp have been elaborated in the previous embodiment, no further details are provided herein.
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Circuit Arrangement For Electric Light Sources In General (AREA)
- Dc-Dc Converters (AREA)
- Control Of El Displays (AREA)
Abstract
Description
VP与VN关系 | 第一输出端1 | 第二输出端2 |
VP>VN | 0 | 1 |
VP<VN | 1 | 0 |
VP=VN | 0 | 0 |
八位逻辑控制信号 | Z1 | Z2 | Z3 | Z4 | Z5 | Z6 | Z7 | Z8 | VREF |
00000000 | 低 | 低 | 低 | 低 | 低 | 低 | 低 | 低 | Vmax |
00000001 | 高 | 低 | 低 | 低 | 低 | 低 | 低 | 低 | Vmax-Vstep |
00000010 | 低 | 高 | 低 | 低 | 低 | 低 | 低 | 低 | Vmax-2Vstep |
...... | Vmax-nVstep | ||||||||
11111111 | 高 | 高 | 高 | 高 | 高 | 高 | 高 | 高 | Vmin |
Claims (17)
- 一种多通道双模式数字控制LED驱动电路,其特征在于,包括:电流采样模块、比较检测模块、数字控制模块和恒流控制模块;所述电流采样模块将负载的电流信号转换为采样电压信号,并输出给比较检测模块和恒流控制模块;所述比较检测模块将采样电压同固定电压进行比较,根据比较结果产生高低电平信号输出至数字控制模块,同时产生一个动态变化的电压信号输出至恒流控制模块;所述数字控制模块根据比较检测模块输出的高低电平信号,对应输出上升或下降的输出信号依次给外部的升压控制模块和驱动模块,实现对负载的反馈调节;所述恒流控制模块根据采样电压,对比固定频率的锯齿波信号,实时产生占空比变化的开关信号,利用开关信号占空比变化控制其内部恒流驱动管的开关状态,实时反馈调节负载的电流。
- 根据权利要求1所述的多通道双模式数字控制LED驱动电路,其特征在于,所述比较检测模块包括:检测单元,用于对采样电压和固定电压进行比较放大,并将放大信号输出给比较单元,固定电压与采样电压的比值越大,输出的放大信号的电压越大;比较单元,用于在检测单元输出的放大信号大于第一阈值电压时,第一输出端输出低电平、第二输出端输出高电平,在检测单元输出的放大信号小于第二阈值电压时,第一输出端输出高电平、第二输出端输出低电平,在检测单元输出的放大信号大于第二阈值电压、且小于第一阈值电压时,第一输出端和第二输出端输出低电平;所述检测单元的输入端连接电流采样模块的输出端,所述检测单元连接比较单元,所述比较单元的第一输出端和第二输出端连接数字控制模块。
- 根据权利要求2所述的多通道双模式数字控制LED驱动电路,其特征在于,所述数字控制模块包括:逻辑单元,用于将比较单元的两个输出端的信号转化为八位逻辑控制信号,当比较单元的第一输出端输出低电平、第二输出端输出高电平时,八位逻辑控制信号从低到高在256位区间内逐位上升;当比较单元的第一输出端输出高电平、第二输出端输出低电平时,八位逻辑控制信号从高到低在256位区间内逐位下降;当比较单元的第一输出端输出低电平、第二输出端输出低电平时,八位逻辑控制信号保持不变;电压控制单元,用于在八位逻辑控制信号每上升一位时,输出电压减小一个步进电压,在八位逻辑控制信号每下降一位时,输出电压增加一个步进电压;所述逻辑单元的第一输入端连接比较单元的第一输出端,所述逻辑单元的第二输入端连接比较单元的第二输出端,所述逻辑单元通过电压控制单元连接外部升压控制模块。
- 根据权利要求3所述的多通道双模式数字控制LED驱动电路,其特征在于,所述电压控制单元包括受八位逻辑控制信号控制的第一电流开关子单元、第二电流开关子单元、第三电流开关子单元、第四电流开关子单元、第五电流开关子单元、第六电流开关子单元、 第七电流开关子单元、第八电流开关子单元、按二进制规则连接的电阻阵列和镜像电流子单元;所述电阻阵列包括第一电阻串、第二电阻串、第三电阻串、第四电阻串、第五电阻串、第六电阻串、第七电阻串、第八电阻串、第九电阻串、第十电阻串、第十一电阻串、第十二电阻串、第十三电阻串、第十四电阻串和第十五电阻串;所述电流开关子单元,用于根据八位逻辑控制信号中对应的逻辑控制信号,输出第一镜像电流给电阻阵列;所述镜像电流子单元,用于输出第二镜像电流给电阻阵列;外部供电端通过第一电流开关子单元连接第一电阻串的一端和第九电阻串的一端,所述第一电阻串的另一端接地;外部供电端通过第二电流开关子单元连接第九电阻串的另一端、第二电阻串的一端和第十电阻串的一端,所述第二电阻串的另一端接地;外部供电端通过第三电流开关子单元连接第十电阻串的另一端、第三电阻串的一端和第十一电阻串的一端,所述第三电阻串的另一端接地;外部供电端通过第四电流开关子单元连接第十一电阻串的另一端、第四电阻串的一端和第十二电阻串的一端,所述第四电阻串的另一端接地;外部供电端通过第五电流开关子单元连接第十二电阻串的另一端、第五电阻串的一端和第十三电阻串的一端,所述第五电阻串的另一端接地;外部供电端通过第六电流开关子单元连接第十三电阻串的另一端、第六电阻串的一端和第十四电阻串的一端,所述第六电阻串的另一端接地;外部供电端通过第七电流开关子单元连接第十四电阻串的另一端、第 七电阻串的一端和第十五电阻串的一端,所述第七电阻串的另一端接地;外部供电端通过第八电流开关子单元和镜像电流子单元连接第十五电阻串的另一端和第八电阻串的一端,所述第八电阻串的另一端接地;所述第八电阻串的一端为电压控制单元的输出端、连接外部升压控制模块。
- 根据权利要求4所述的多通道双模式数字控制LED驱动电路,其特征在于,所述电流采样模块包括第一电阻、第二电阻、第一MOS管和第二MOS管;所述第一电阻的一端连接负载,所述第一电阻的另一端连接第一MOS管的漏极,所述第一MOS管的源极通过第二电阻连接第二MOS管的漏极,所述第二MOS管的漏极为电流采样模块的输出端,所述第二MOS管的栅极和源极接地。
- 根据权利要求5所述的多通道双模式数字控制LED驱动电路,其特征在于,所述检测单元包括第一运算放大器、第一电容、第二电容、第三电容、第三电阻、第四电阻、第三MOS管、第四MOS管、第五MOS管和第六MOS管;所述第一运算放大器的反相输入端为检测单元的输入端、连接第二MOS管的漏极,所述第一运算放大器的正相输入端连接固定电压提供端,所述第一运算放大器的输出端连接第一电容的一端、第三MOS管的漏极、第二电容的一端和第四MOS管的栅极,所述第一电容的另一端通过第三电阻连接第三MOS管的源极、第五MOS管的漏极、第二电容的另一端、第四MOS管的源极和第六MOS管的漏极,所述第三MOS管的栅极连接使能信号,所述第五MOS管的漏极还连接第一运算放大器的反相输入端, 所述第五MOS管的源极连接第一运算放大器的正相输入端、还通过第三电容接地,所述第五MOS管的栅极连接PWM反相信号提供端;所述第四MOS管的漏极通过第四电阻连接外部供电端,所述第四MOS管的源极为检测单元的输出端、连接比较单元的输入端和恒流控制模块;所述第六MOS管的源极接地。
- 根据权利要求6所述的多通道双模式数字控制LED驱动电路,其特征在于,所述比较单元包括第一比较器、第二比较器、第一缓冲器和第二缓冲器;所述第一比较器的正相输入端连接第一阈值电压提供端,所述第一比较器的反相输入端和第二比较器的正相输入端连接第四MOS管的源极,所述第二比较器的反相输入端连接第二阈值电压提供端;所述第一比较器的输出端连接第一缓冲器的输入端,所述第一缓冲器的输出端为比较单元的第一输出端,所述第二比较器的输出端连接第二缓冲器的输入端,所述第二缓冲器的输出端为比较单元的第二输出端。
- 根据权利要求7所述的多通道双模式数字控制LED驱动电路,其特征在于,所述第一电流开关子单元、第二电流开关子单元、第三电流开关子单元、第四电流开关子单元、第五电流开关子单元、第六电流开关子单元、第七电流开关子单元和第八电流开关子单元均相同;每个电流开关子单元均包括两个PMOS管和一个开关管;两个PMOS管为共源共栅偏置电流源结构:一个PMOS管的源极连接外部供电端、漏极连接另一个PMOS管的源极,另一个PMOS管的漏极连接开关管的源极;开关管的栅极对应连接逻辑单元的输出端, 开关管的漏极为电流开关子单元的输出端、通过电阻串接地。
- 根据权利要求8所述的多通道双模式数字控制LED驱动电路,其特征在于,所述恒流控制模块包括第三比较器和第二运算放大器,所述第三比较器的正相输入端连接检测单元的输出端,第三比较器的反相输入端连接LED驱动系统内部固有的低频锯齿波信号提供端,所述第三比较器的输出端连接第二运算放大器的电源负端,所述第二运算放大器的电源正端连接外部供电端VCC;所述第二运算放大器的正向输入端连接高电压信号提供端,所述第二运算放大器的反向输入端连接采样模块的输出端,所述第二运算放大器的输出端连接负载。
- 一种LED灯,其特征在于,包括如权利要求1所述的多通道双模式数字控制LED驱动电路;所述多通道双模式数字控制LED驱动电路包括:电流采样模块、比较检测模块、数字控制模块和恒流控制模块;所述电流采样模块将负载的电流信号转换为采样电压信号,并输出给比较检测模块和恒流控制模块;所述比较检测模块将采样电压同固定电压进行比较,根据比较结果产生高低电平信号输出至数字控制模块,同时产生一个动态变化的电压信号输出至恒流控制模块;所述数字控制模块根据比较检测模块输出的高低电平信号,对应输出上升或下降的输出信号依次给外部的升压控制模块和驱动模块,实现对负载的反馈调节;所述恒流控制模块根据采样电压,对比固定频率的锯齿波信号,实时产生占空比变化的开关信号,利用开关信号占空比变 化控制其内部恒流驱动管的开关状态,实时反馈调节负载的电流。
- 根据权利要求10所述的LED灯,其特征在于,所述比较检测模块包括:检测单元,用于对采样电压和固定电压进行比较放大,并将放大信号输出给比较单元,固定电压与采样电压的比值越大,输出的放大信号的电压越大;比较单元,用于在检测单元输出的放大信号大于第一阈值电压时,第一输出端输出低电平、第二输出端输出高电平,在检测单元输出的放大信号小于第二阈值电压时,第一输出端输出高电平、第二输出端输出低电平,在检测单元输出的放大信号大于第二阈值电压、且小于第一阈值电压时,第一输出端和第二输出端输出低电平;所述检测单元的输入端连接电流采样模块的输出端,所述检测单元连接比较单元,所述比较单元的第一输出端和第二输出端连接数字控制模块。
- 根据权利要求11所述的LED灯,其特征在于,所述数字控制模块包括:逻辑单元,用于将比较单元的两个输出端的信号转化为八位逻辑控制信号,当比较单元的第一输出端输出低电平、第二输出端输出高电平时,八位逻辑控制信号从低到高在256位区间内逐位上升;当比较单元的第一输出端输出高电平、第二输出端输出低电平时,八位逻辑控制信号从高到低在256位区间内逐位下降;当比较单元的第一输出端输出低电平、第二输出端输出低电平时,八位逻辑控制信号保持 不变;电压控制单元,用于在八位逻辑控制信号每上升一位时,输出电压减小一个步进电压,在八位逻辑控制信号每下降一位时,输出电压增加一个步进电压;所述逻辑单元的第一输入端连接比较单元的第一输出端,所述逻辑单元的第二输入端连接比较单元的第二输出端,所述逻辑单元通过电压控制单元连接外部升压控制模块。
- 根据权利要求12所述的LED灯,其特征在于,所述电压控制单元包括受八位逻辑控制信号控制的第一电流开关子单元、第二电流开关子单元、第三电流开关子单元、第四电流开关子单元、第五电流开关子单元、第六电流开关子单元、第七电流开关子单元、第八电流开关子单元、按二进制规则连接的电阻阵列和镜像电流子单元;所述电阻阵列包括第一电阻串、第二电阻串、第三电阻串、第四电阻串、第五电阻串、第六电阻串、第七电阻串、第八电阻串、第九电阻串、第十电阻串、第十一电阻串、第十二电阻串、第十三电阻串、第十四电阻串和第十五电阻串;所述电流开关子单元,用于根据八位逻辑控制信号中对应的逻辑控制信号,输出第一镜像电流给电阻阵列;所述镜像电流子单元,用于输出第二镜像电流给电阻阵列;外部供电端通过第一电流开关子单元连接第一电阻串的一端和第九电阻串的一端,所述第一电阻串的另一端接地;外部供电端通过第二电流开关子单元连接第九电阻串的另一端、第二电阻串的一端和 第十电阻串的一端,所述第二电阻串的另一端接地;外部供电端通过第三电流开关子单元连接第十电阻串的另一端、第三电阻串的一端和第十一电阻串的一端,所述第三电阻串的另一端接地;外部供电端通过第四电流开关子单元连接第十一电阻串的另一端、第四电阻串的一端和第十二电阻串的一端,所述第四电阻串的另一端接地;外部供电端通过第五电流开关子单元连接第十二电阻串的另一端、第五电阻串的一端和第十三电阻串的一端,所述第五电阻串的另一端接地;外部供电端通过第六电流开关子单元连接第十三电阻串的另一端、第六电阻串的一端和第十四电阻串的一端,所述第六电阻串的另一端接地;外部供电端通过第七电流开关子单元连接第十四电阻串的另一端、第七电阻串的一端和第十五电阻串的一端,所述第七电阻串的另一端接地;外部供电端通过第八电流开关子单元和镜像电流子单元连接第十五电阻串的另一端和第八电阻串的一端,所述第八电阻串的另一端接地;所述第八电阻串的一端为电压控制单元的输出端、连接外部升压控制模块。
- 根据权利要求13所述的LED灯,其特征在于,所述电流采样模块包括第一电阻、第二电阻、第一MOS管和第二MOS管;所述第一电阻的一端连接负载,所述第一电阻的另一端连接第一MOS管的漏极,所述第一MOS管的源极通过第二电阻连接第二MOS管的漏极,所述第二MOS管的漏极为电流采样模块的输出端,所述第二MOS管的栅极和源极接地。
- 根据权利要求14所述的LED灯,其特征在于,所述检测 单元包括第一运算放大器、第一电容、第二电容、第三电容、第三电阻、第四电阻、第三MOS管、第四MOS管、第五MOS管和第六MOS管;所述第一运算放大器的反相输入端为检测单元的输入端、连接第二MOS管的漏极,所述第一运算放大器的正相输入端连接固定电压提供端,所述第一运算放大器的输出端连接第一电容的一端、第三MOS管的漏极、第二电容的一端和第四MOS管的栅极,所述第一电容的另一端通过第三电阻连接第三MOS管的源极、第五MOS管的漏极、第二电容的另一端、第四MOS管的源极和第六MOS管的漏极,所述第三MOS管的栅极连接使能信号,所述第五MOS管的漏极还连接第一运算放大器的反相输入端,所述第五MOS管的源极连接第一运算放大器的正相输入端、还通过第三电容接地,所述第五MOS管的栅极连接PWM反相信号提供端;所述第四MOS管的漏极通过第四电阻连接外部供电端,所述第四MOS管的源极为检测单元的输出端、连接比较单元的输入端和恒流控制模块;所述第六MOS管的源极接地。
- 根据权利要求15所述的LED灯,其特征在于,所述比较单元包括第一比较器、第二比较器、第一缓冲器和第二缓冲器;所述第一比较器的正相输入端连接第一阈值电压提供端,所述第一比较器的反相输入端和第二比较器的正相输入端连接第四MOS管的源极,所述第二比较器的反相输入端连接第二阈值电压提供端;所述第一比较器的输出端连接第一缓冲器的输入端,所述第一缓冲器的输出端为比较单元的第一输出端,所述第二比较器的输出端连接第二缓冲器的 输入端,所述第二缓冲器的输出端为比较单元的第二输出端。
- 根据权利要求16所述的LED灯,其特征在于,所述第一电流开关子单元、第二电流开关子单元、第三电流开关子单元、第四电流开关子单元、第五电流开关子单元、第六电流开关子单元、第七电流开关子单元和第八电流开关子单元均相同;每个电流开关子单元均包括两个PMOS管和一个开关管;两个PMOS管为共源共栅偏置电流源结构:一个PMOS管的源极连接外部供电端、漏极连接另一个PMOS管的源极,另一个PMOS管的漏极连接开关管的源极;开关管的栅极对应连接逻辑单元的输出端,开关管的漏极为电流开关子单元的输出端、通过电阻串接地。根据权利要求17所述的LED灯,其特征在于,所述恒流控制模块包括第三比较器和第二运算放大器,所述第三比较器的正相输入端连接检测单元的输出端,第三比较器的反相输入端连接LED驱动系统内部固有的低频锯齿波信号提供端,所述第三比较器的输出端连接第二运算放大器的电源负端,所述第二运算放大器的电源正端连接外部供电端VCC;所述第二运算放大器的正向输入端连接高电压信号提供端,所述第二运算放大器的反向输入端连接采样模块的输出端,所述第二运算放大器的输出端连接负载。
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU2016263606A AU2016263606B2 (en) | 2015-05-19 | 2016-02-01 | Multi-channel dual-mode digital control LED driving circuit and LED lamp |
US15/507,385 US10143072B2 (en) | 2015-05-19 | 2016-02-01 | Multi-channel dual-mode digital control LED driving circuit and LED lamp |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN2015102552612 | 2015-05-19 | ||
CN201510255261.2A CN104883780B (zh) | 2015-05-19 | 2015-05-19 | 多通道双模式数字控制led驱动电路及led灯 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2016184169A1 true WO2016184169A1 (zh) | 2016-11-24 |
Family
ID=53951072
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/CN2016/073082 WO2016184169A1 (zh) | 2015-05-19 | 2016-02-01 | 多通道双模式数字控制led驱动电路及led灯 |
Country Status (4)
Country | Link |
---|---|
US (1) | US10143072B2 (zh) |
CN (1) | CN104883780B (zh) |
AU (1) | AU2016263606B2 (zh) |
WO (1) | WO2016184169A1 (zh) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110234188A (zh) * | 2019-05-08 | 2019-09-13 | 深圳市富满电子集团股份有限公司 | Led驱动芯片的自动换挡调节电路 |
CN113115496A (zh) * | 2021-05-14 | 2021-07-13 | 东莞芯成电子科技有限公司 | 单电源双高功率led驱动系统 |
CN115309220A (zh) * | 2022-08-16 | 2022-11-08 | 上海芯问科技有限公司 | 一种磁敏蛋白质传感器的读出电路 |
Families Citing this family (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104883780B (zh) | 2015-05-19 | 2017-06-23 | 深圳创维-Rgb电子有限公司 | 多通道双模式数字控制led驱动电路及led灯 |
CN105142293B (zh) * | 2015-09-16 | 2017-12-26 | 英特格灵芯片(天津)有限公司 | 一种反馈驱动电路 |
CN106163006A (zh) * | 2016-08-03 | 2016-11-23 | 袁志贤 | 用于led设备的驱动电路 |
CN108075750B (zh) * | 2016-11-14 | 2023-06-30 | 恩智浦有限公司 | 电流钳位电路 |
CN107727907B (zh) * | 2017-09-28 | 2020-10-09 | 歌尔股份有限公司 | 电流检测装置 |
CN107820346A (zh) * | 2017-11-14 | 2018-03-20 | 上海莱托思电子科技有限公司 | 一种数码化多通道线性控制模块、系统及方法 |
TWI654903B (zh) * | 2017-12-21 | 2019-03-21 | 友達光電股份有限公司 | 發光二極體的驅動裝置及其驅動方法 |
CN108495420B (zh) * | 2018-05-09 | 2023-11-28 | 福建吉艾普光影科技有限公司 | 一种多路恒流输出驱动板的快速检测系统 |
CN108834263B (zh) * | 2018-07-27 | 2023-09-12 | 深圳市明微电子股份有限公司 | 一种电压可调的调光控制电路及系统 |
CN109314512B (zh) * | 2018-08-31 | 2022-05-20 | 深圳市汇顶科技股份有限公司 | 逆流开关 |
CN108944653B (zh) * | 2018-09-14 | 2024-05-14 | 常州瑞阳电装有限公司 | 一种全域式闪光器驱动电路 |
JP2020155203A (ja) * | 2019-03-18 | 2020-09-24 | セイコーエプソン株式会社 | 発光制御装置、光源装置及び投写型映像表示装置 |
CN109831853A (zh) * | 2019-04-09 | 2019-05-31 | 攀枝花学院 | 一种灯具智能控制系统 |
CN113015287B (zh) * | 2019-12-20 | 2024-02-06 | 美芯晟科技(北京)股份有限公司 | 一种驱动电路、相关电路和装置 |
US11108385B1 (en) * | 2020-06-22 | 2021-08-31 | Pixart Imaging Inc. | Phase shifter circuit of optical encoder and operating method thereof |
CN111800906A (zh) * | 2020-07-03 | 2020-10-20 | 广东奥普特科技股份有限公司 | 一种检测光源参数的控制电路和控制方法 |
CN112039504B (zh) * | 2020-09-16 | 2024-05-07 | 拓尔微电子股份有限公司 | 一种pwm信号占空比调节电路 |
CN112834913B (zh) * | 2021-01-08 | 2024-04-26 | 胜达克半导体科技(上海)股份有限公司 | 一种堆叠测试机通道的高压测试方法 |
CN114170978B (zh) * | 2021-12-15 | 2023-04-07 | 北京芯格诺微电子有限公司 | 用于显示的背光led矩阵驱动装置及故障检测方法 |
CN114302532B (zh) * | 2021-12-29 | 2024-01-30 | 江苏众辉电子科技有限公司 | Led频闪驱动芯片 |
CN114423116B (zh) * | 2022-03-29 | 2022-06-17 | 深圳市必易微电子股份有限公司 | 调光控制电路、调光控制方法和led驱动电路 |
CN116708997B (zh) * | 2023-08-09 | 2023-10-27 | 深圳市锐斯特科技有限公司 | 一种行车记录仪远程快门控制装置 |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003264316A (ja) * | 2002-03-11 | 2003-09-19 | Fuji Electric Co Ltd | Led制御回路 |
CN101340760A (zh) * | 2007-07-06 | 2009-01-07 | Nec液晶技术株式会社 | 发光控制电路、发光控制方法、平面照明装置和具有该平面照明装置的液晶显示装置 |
CN201928475U (zh) * | 2010-06-02 | 2011-08-10 | 上海芯龙半导体有限公司 | 具有升压和升降压功能的大功率led灯驱动单片集成电路 |
CN103037597A (zh) * | 2013-01-06 | 2013-04-10 | 深圳创维-Rgb电子有限公司 | 多路led恒流控制电路及led光源控制系统 |
CN203984727U (zh) * | 2014-06-12 | 2014-12-03 | 欧普照明股份有限公司 | 一种用于led灯的pwm调光电路 |
CN104883780A (zh) * | 2015-05-19 | 2015-09-02 | 深圳创维-Rgb电子有限公司 | 多通道双模式数字控制led驱动电路及led灯 |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TWI248598B (en) * | 2002-12-31 | 2006-02-01 | Hon Hai Prec Ind Co Ltd | Driving apparatus of LED |
JP4772336B2 (ja) * | 2004-02-27 | 2011-09-14 | ローム株式会社 | 駆動制御回路 |
US7288902B1 (en) * | 2007-03-12 | 2007-10-30 | Cirrus Logic, Inc. | Color variations in a dimmable lighting device with stable color temperature light sources |
CN101605413B (zh) * | 2009-07-06 | 2012-07-04 | 英飞特电子(杭州)有限公司 | 适用于可控硅调光的led驱动电路 |
CN201718099U (zh) * | 2010-07-07 | 2011-01-19 | 盛飞 | Led驱动电源 |
TW201215230A (en) * | 2010-09-27 | 2012-04-01 | Advanced Connectek Inc | Light emitting element driving circuit |
CN102340911B (zh) * | 2010-12-30 | 2013-08-07 | 矽力杰半导体技术(杭州)有限公司 | 一种led驱动器的控制电路及其控制方法 |
CN202404873U (zh) * | 2011-11-16 | 2012-08-29 | 武汉光动能科技有限公司 | Led显示屏的恒压恒流驱动电路 |
EP2642823B1 (en) * | 2012-03-24 | 2016-06-15 | Dialog Semiconductor GmbH | Method for optimizing efficiency versus load current in an inductive boost converter for white LED driving |
US9252662B2 (en) * | 2013-04-17 | 2016-02-02 | Cooledge Lighting, Inc. | Illumination device control systems and methods |
CN103491682B (zh) * | 2013-09-22 | 2015-06-03 | 辉芒微电子(深圳)有限公司 | 一种控制峰值电流的线性开关恒流led驱动电路 |
CN104244513A (zh) * | 2014-08-07 | 2014-12-24 | 矽力杰半导体技术(杭州)有限公司 | 一种多路led恒流驱动电路、驱动方法及led驱动电源 |
-
2015
- 2015-05-19 CN CN201510255261.2A patent/CN104883780B/zh active Active
-
2016
- 2016-02-01 US US15/507,385 patent/US10143072B2/en active Active
- 2016-02-01 WO PCT/CN2016/073082 patent/WO2016184169A1/zh active Application Filing
- 2016-02-01 AU AU2016263606A patent/AU2016263606B2/en active Active
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003264316A (ja) * | 2002-03-11 | 2003-09-19 | Fuji Electric Co Ltd | Led制御回路 |
CN101340760A (zh) * | 2007-07-06 | 2009-01-07 | Nec液晶技术株式会社 | 发光控制电路、发光控制方法、平面照明装置和具有该平面照明装置的液晶显示装置 |
CN201928475U (zh) * | 2010-06-02 | 2011-08-10 | 上海芯龙半导体有限公司 | 具有升压和升降压功能的大功率led灯驱动单片集成电路 |
CN103037597A (zh) * | 2013-01-06 | 2013-04-10 | 深圳创维-Rgb电子有限公司 | 多路led恒流控制电路及led光源控制系统 |
CN203984727U (zh) * | 2014-06-12 | 2014-12-03 | 欧普照明股份有限公司 | 一种用于led灯的pwm调光电路 |
CN104883780A (zh) * | 2015-05-19 | 2015-09-02 | 深圳创维-Rgb电子有限公司 | 多通道双模式数字控制led驱动电路及led灯 |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110234188A (zh) * | 2019-05-08 | 2019-09-13 | 深圳市富满电子集团股份有限公司 | Led驱动芯片的自动换挡调节电路 |
CN113115496A (zh) * | 2021-05-14 | 2021-07-13 | 东莞芯成电子科技有限公司 | 单电源双高功率led驱动系统 |
CN115309220A (zh) * | 2022-08-16 | 2022-11-08 | 上海芯问科技有限公司 | 一种磁敏蛋白质传感器的读出电路 |
Also Published As
Publication number | Publication date |
---|---|
AU2016263606A1 (en) | 2017-03-02 |
AU2016263606B2 (en) | 2018-02-08 |
US20170295632A1 (en) | 2017-10-12 |
CN104883780A (zh) | 2015-09-02 |
US10143072B2 (en) | 2018-11-27 |
CN104883780B (zh) | 2017-06-23 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2016184169A1 (zh) | 多通道双模式数字控制led驱动电路及led灯 | |
CN101226412B (zh) | 恒流电路及使用恒流电路的发光二极管驱动装置 | |
CN105940609B (zh) | 缓冲器电路和方法 | |
WO2022127468A1 (zh) | 供电电路、驱动芯片以及显示装置 | |
US8742689B2 (en) | Light emitting diode driving apparatus | |
US20080043008A1 (en) | Multifunctional Driver Controllers | |
US7583068B2 (en) | Method for driving voltage-controlled devices or current-controlled devices | |
CN102196621B (zh) | 一种led调光电路 | |
CN1960174A (zh) | 差动放大器及半导体电路 | |
TW201434344A (zh) | 發光二極體驅動裝置 | |
CN102316644B (zh) | 一种高精度led恒流驱动装置 | |
CN108617061B (zh) | 驱动电流调节装置 | |
CN115397063B (zh) | 一种miniLED驱动电路 | |
US9024664B2 (en) | Current-to-voltage converter and electronic apparatus thereof | |
CN108712801B (zh) | 一种宽输入电压的恒功率驱动电路及装置 | |
TWI559812B (zh) | 定電流驅動裝置之回授裝置及回授方法 | |
US9161405B2 (en) | Light emitting diode driving circuit and system | |
CN112816773A (zh) | 一种电流采样电路 | |
CN212112265U (zh) | 一种线性稳压电路 | |
CN117059020B (zh) | 一种低转折电压的led显示屏驱动电路及led显示屏 | |
CN108617060B (zh) | 一种宽输入电压的恒流明驱动电路及装置 | |
TWI825698B (zh) | 電壓調整器與訊號放大電路 | |
CN216752168U (zh) | 一种pwm信号电压调节电路及电子设备 | |
CN117477953A (zh) | 多路电压输出可调的电源模块 | |
CN116069096A (zh) | 一种高电源纹波抑制比的ldo电路 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 16795656 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 15507385 Country of ref document: US |
|
ENP | Entry into the national phase |
Ref document number: 2016263606 Country of ref document: AU Date of ref document: 20160201 Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 16795656 Country of ref document: EP Kind code of ref document: A1 |