CN110415641A - A kind of two-wire cascade LED drive circuit - Google Patents
A kind of two-wire cascade LED drive circuit Download PDFInfo
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- CN110415641A CN110415641A CN201910791946.7A CN201910791946A CN110415641A CN 110415641 A CN110415641 A CN 110415641A CN 201910791946 A CN201910791946 A CN 201910791946A CN 110415641 A CN110415641 A CN 110415641A
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
- G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
- G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
Abstract
The present invention relates to LED Drive Control Technique fields, and in particular to a kind of two-wire cascade LED drive circuit.Including data/address bus, clock bus and several LED drive chips, the LED drive chip carries out two-wire cascade by data/address bus and clock bus, the data/address bus is used to provide drive control data for LED drive chip, clock bus is used to provide clock for LED drive chip referring to data, the driving end of the LED drive chip is connected with LED light group, and the LED light group includes the LED light of several capable of emitting different colored light sources.The present invention can be transmitted by double-wire signal realizes the luminous cascade Mach-Zehnder interferometer of efficient LED colour dot lattice, guarantees accurately time cooperation relationship, improves synchronous refresh display effect.
Description
Technical field
The present invention relates to LED Drive Control Technique fields, and in particular to a kind of two-wire cascade LED drive circuit.
Background technique
LED, that is, light emitting diode abbreviation, it is one kind of semiconductor diode, electric energy can be converted to luminous energy.Hair
Optical diode is made of as general-purpose diode a PN junction, it may have unilateral conduction.It is added when to light emitting diode
After forward voltage, the hole in the area N is injected into from the area P and is injected into the electronics in the area P by the area N, near the PN junction in a few micrometers respectively
With the electronics in the area N and the hole-recombination in the area P, the fluorescence of spontaneous radiation is generated.The application of light emitting diode (LED) is broadly divided into
Two general orientation of display function and illumination functions, due to scientific and technological continuous progress, traditional single color LED (LED) is gradually
It is gradually unable to satisfy the demand of human vision, so having developed dichromatic LED (LED), full-color light-emitting diode successively
(LED) Related products such as.Full-color light-emitting diode is the presentation that can reach various colors, so each all-colour LED encapsulation knot
In structure, including at least having feux rouges (R) LED, green light (G) LED and blue light (B) LED, to utilize feux rouges (R), green light (G) and blue light
(B) primaries blend ever-changing light color, but because the ratio of various photochromic required RGB primaries
Example is all different, therefore full-color light-emitting diode requires external collocation current-limiting resistance and driving unit effectively accurately to control RGB
Trichromatic light mixng proportion.
It adopts and computerizeds control, the Intelligent full-color display screen that light, electricity combine together has been applied in wide range of areas,
Its pixel uses Light-emitting diode LED, and many light emitting diodes are lined up with dot matrix way, constitutes LED array, in turn
Constitute LED screen.By different LED driving methods, the image of different-effect can be obtained.Therefore the superiority and inferiority of LED drive chip,
It plays an important role to the display quality of LED display.In LED landscape brightening application market, since each LED drives core
The lamp point number that piece can drive is limited, to realize large-scale lamp decoration system, must just cascade to LED drive chip
To cascade more lamp points.The lamp point refers to a pixel, can be made of three LED light, such as red LED lamp, green
Color LED light and blue LED lamp.Existing LED drive chip is when being cascaded, not good enough, timing that there is also bus transfer efficiency
Cooperate poor defect, needs further to be improved.
Summary of the invention
The present invention provides a kind of two-wires to cascade LED drive circuit, realizes in application, can be transmitted by double-wire signal
The efficient luminous cascade Mach-Zehnder interferometer of LED colour dot lattice, guarantees accurately time cooperation relationship, improves synchronous refresh display effect.
The technical scheme adopted by the invention is as follows:
A kind of two-wire cascade LED drive circuit, including data/address bus, clock bus and several LED drive chips, it is described
LED drive chip carries out two-wire cascade by data/address bus and clock bus, and the data/address bus for LED drive chip for mentioning
For drive control data, clock bus is used to provide clock for LED drive chip referring to data, the drive of the LED drive chip
Moved end is connected with LED light group, and the LED light group includes the LED light of several capable of emitting different colored light sources.
As a preferred embodiment of the above technical solution, the LED drive chip includes decoder module, data processing module, oscillation
Device module, drive control module, IBIAS module and several field effect transistors, the decoder module and data/address bus and clock
Bus docking is decoded for the data to data/address bus and clock bus transmission, and decoded data is reached data
Processing module, meanwhile, decoder module is also used to that remaining data flow shaping will be distinguished on data/address bus and clock bus, and transmits
To next cascade LED drive chip, the oscillator module provides internal reference source for data processing module, institute
Data processing module is stated for sending drive control order to drive control module, the IBIAS module is used for drive control
Module provides bias current, and the drive control module is used to control electric current, each field by field effect transistor output driving
Effect transistor output end connects the LED light of a corresponding color light source.
As a preferred embodiment of the above technical solution, the LED light group includes red LED lamp, green light LED lamp and blue LED lamp,
LED drive chip sets three driving ends and is separately connected red LED lamp, green light LED lamp and blue LED lamp.
As a preferred embodiment of the above technical solution, the LED drive chip be equipped with VDD, GND, SDI, SDO, CKI, CKO,
OUTR, OUTG and OUTB interface, the VDD interface and GND interface are respectively power access end and the ground connection of LED drive chip
End, the SDI interface and CKI interface are respectively the incoming end of data/address bus and clock bus, the SDO interface and CKO interface
Respectively data/address bus and clock bus picks out end, and OUTR, OUTG and OUTB interface is respectively used to connection red-light LED
Lamp, green light LED lamp and blue LED lamp.
As a preferred embodiment of the above technical solution, the initial end of the data/address bus and clock bus is connected with external control
Device, the peripheral control unit, which is used to distinguish output driving by data/address bus and clock bus, controls data and clock referring to number
According to.
As a preferred embodiment of the above technical solution, the drive control module is equipped with pwm unit, pulse width
Modulation unit is connect with each field effect transistor.
As a preferred embodiment of the above technical solution, there are three the field effect transistor is set, the grid of three field effect transistors
Pole is all connected with drive control module, source grounding, and drain electrode is separately connected OUTR, OUTG and OUTB interface.
As a preferred embodiment of the above technical solution, the LED drive chip accesses 5V supply voltage by VDD interface.
As a preferred embodiment of the above technical solution, the oscillator module selects built-in RC oscillator.
The invention has the benefit that
The present invention sets drive control data and clock referring to data by peripheral control unit and then passes through data respectively
Bus and clock bus are transmitted to cascade LED drive chip, and the decoder module in LED drive chip is to data/address bus and clock
The data of bus transfer are decoded, and the drive control data and clock for obtaining this grade of LED drive chip are sent referring to data
To data processing module, then remaining data flow shaping will be distinguished on data/address bus and clock bus, and be transmitted to next
Cascade LED drive chip, after data processing module obtains drive control data and clock reference data, according to oscillator module
The internal reference source of offer determines that accurately time point is selected to drive control module transmission control command, oscillator module
With built-in RC oscillator, to provide the internal reference source of high-precision, high stability, the effect of IBIAS module is to pass through
One feedback loop generates a reference current, and this reference current is exported by the current mirror of different proportion to drive control
Module is as bias current, after drive control module is modulated according to the bias current that control command provides IBIAS module,
Light emitting control is carried out by the LED light that field effect transistor exports corresponding color light source, efficient LED colour dot lattice is realized with this
Shine cascade Mach-Zehnder interferometer, guarantees accurately time cooperation relationship, improves synchronous refresh display effect.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this
Some embodiments of invention for those of ordinary skill in the art without creative efforts, can be with
It obtains other drawings based on these drawings.
Fig. 1 is each LED drive chip two-wire cascade circuit schematic diagram of the present invention；
Fig. 2 is LED drive chip internal structure schematic block diagram of the invention；
Fig. 3 is each interface diagram of LED drive chip of the invention；
Fig. 4 is that two-wire inputs agreement waveform diagram.
Specific embodiment
With reference to the accompanying drawing and specific embodiment the present invention is further elaborated.It should be noted that for this
The explanation of a little way of example is used to help understand the present invention, but and does not constitute a limitation of the invention.It is disclosed herein specific
Structure and function details is only used for description example embodiments of the present invention.However, this hair can be embodied with many alternative forms
It is bright, and be not construed as limiting the invention in embodiment set forth herein.
It should be appreciated that term first, second etc. is only used for distinguishing description, it is not understood to indicate or imply relatively important
Property.Although term first, second etc. can be used herein to describe various units, these units should not be by these terms
Limitation.These terms are only used to distinguish a unit and another unit.Such as first unit can be referred to as second unit,
And similarly second unit can be referred to as first unit, without departing from the range of example embodiments of the present invention.
It should be appreciated that the terms "and/or", only a kind of incidence relation for describing affiliated partner, expression can be with
There are three kinds of relationships, for example, A and/or B, can indicate: individualism A, individualism B exist simultaneously tri- kinds of situations of A and B,
The terms "/and " are to describe another affiliated partner relationship, indicate may exist two kinds of relationships, can be with for example, A/ and B
Indicate: two kinds of situations of individualism A, individualism A and B, in addition, character "/" herein, typicallying represent forward-backward correlation object is
A kind of "or" relationship.
It should be appreciated that in the description of the present invention, the orientation or position of the instructions such as term " on ", "vertical", "inner", "outside"
Relationship is the invention product using when the orientation or positional relationship usually put or those skilled in the art usually understand
Orientation or positional relationship, be merely for convenience of description of the present invention and simplification of the description, rather than the device of indication or suggestion meaning
Or element must have a particular orientation, be constructed and operated in a specific orientation, therefore be not considered as limiting the invention.
It should be appreciated that when by unit referred to as with another unit " connection ", " connected " or " coupling " when, it can with it is another
A unit is directly connected or couples or temporary location may exist.Relatively, it is referred to as with another unit " directly when by unit
It is connected " or when " direct-coupling ", temporary location is not present.It should explain in a similar manner for describing the relationship between unit
Other words (for example, " ... between " to " between directly existing ... ", " adjacent " is to " direct neighbor " etc.).
In the description of the present invention, it is also necessary to which explanation is unless specifically defined or limited otherwise, term " setting ",
" installation ", " connection " shall be understood in a broad sense, for example, it may be being fixedly connected, may be a detachable connection, or integrally connect
It connects；It can be mechanical connection, be also possible to be electrically connected；It can be directly connected, can also indirectly connected through an intermediary, it can
To be the connection inside two elements.For the ordinary skill in the art, above-mentioned term can be understood with concrete condition
Concrete meaning in the present invention.
Terms used herein are only used for description specific embodiment, and are not intended to limitation example embodiments of the present invention.
As it is used herein, singular "a", "an" and "the" is intended to include plural form, unless context is explicitly indicated
Contrary.It should also be understood that term " includes ", " including ", "comprising", and/or " containing " are as used herein,
Specified stated feature, integer, step, operation, unit and/or component existence, and be not excluded for it is one or more its
His feature, quantity, step, operation, unit, component and/or their combination existence or increase.
It will be further noted that the function action occurred may be with the sequence of attached drawing appearance in some alternative embodiments
It is different.Such as it depends on substantially being executed concurrently in related function action, or sometimes can be with
Opposite sequence executes continuously show two figures.
Specific details is provided, in the following description in order to which example embodiment is understood completely.However ability
Domain those of ordinary skill is it is to be understood that implementation example embodiment without these specific details.Such as it can be
System is shown in block diagram, to avoid with unnecessary details come so that example is unclear.It in other embodiments, can not be with non-
Necessary details shows well-known process, structure and technology, to avoid making example embodiment unclear.
Embodiment 1:
A kind of two-wire cascade LED drive circuit is present embodiments provided, as shown in Figure 1 to Figure 2:
Including data/address bus, clock bus and several LED drive chips, the LED drive chip by data/address bus and
Clock bus carries out two-wire cascade, and the data/address bus is used to provide drive control data for LED drive chip, and clock bus is used
In providing clock referring to data for LED drive chip, the driving end of the LED drive chip is connected with LED light group, the LED
Lamp group includes the LED light of several capable of emitting different colored light sources, and the LED drive chip includes decoder module (i.e. in Fig. 2
DECODE), data processing module (i.e. MCU in Fig. 2), oscillator module (i.e. OSC in Fig. 2), drive control module (are schemed
DRV in 2), IBIAS module and several field effect transistors, the decoder module (i.e. DECODE in Fig. 2) and data/address bus
It docks, is decoded for the data to data/address bus and clock bus transmission, and decoded data are passed with clock bus
To data processing module (i.e. MCU in Fig. 2), meanwhile, decoder module (i.e. DECODE in Fig. 2) be also used to data/address bus and
Remaining data flow shaping is distinguished on clock bus, and is transmitted to next cascade LED drive chip, the oscillator module
(i.e. OSC in Fig. 2) is that data processing module (i.e. MCU in Fig. 2) provides internal reference source, the data processing mould
Block (i.e. MCU in Fig. 2) is used to send drive control order, the IBIAS mould to drive control module (i.e. DRV in Fig. 2)
Block is used to provide bias current, the drive control module (i.e. DRV in Fig. 2) to drive control module (i.e. DRV in Fig. 2)
For controlling electric current by field effect transistor output driving, each field effect transistor output end connects a corresponding color light
The LED light in source.The initial end of the data/address bus and clock bus is connected with peripheral control unit, and the peripheral control unit is for leading to
Data/address bus and clock bus difference output driving control data and clock are crossed referring to data.It by outside in application, can be controlled
Device processed sets drive control data and clock referring to data and then is transmitted to cascade by data/address bus and clock bus respectively
LED drive chip, the decoder module (i.e. DECODE in Fig. 2) in LED drive chip passes data/address bus and clock bus
Defeated data are decoded, and the drive control data and clock for obtaining this grade of LED drive chip are sent to data referring to data
Processing module (i.e. MCU in Fig. 2) then will be distinguished remaining data flow shaping, and be transmitted on data/address bus and clock bus
To next cascade LED drive chip, data processing module (i.e. MCU in Fig. 2) obtains drive control data and clock ginseng
After data, according to oscillator module (i.e. OSC in Fig. 2) provide internal reference source determine accurately time point to
Drive control module (i.e. DRV in Fig. 2) sends control command, and oscillator module (i.e. OSC in Fig. 2) selects built-in RC oscillation
Device, to provide the internal reference source of high-precision, high stability, the effect of IBIAS module is produced by a feedback loop
A raw reference current, and this reference current is exported to drive control module (i.e. in Fig. 2 by the current mirror of different proportion
DRV) be used as bias current, drive control module (i.e. DRV in Fig. 2) provides IBIAS module according to control command inclined
It sets after electric current is modulated, light emitting control is carried out by the LED light that field effect transistor exports corresponding color light source, is realized with this
The efficient luminous cascade Mach-Zehnder interferometer of LED colour dot lattice, guarantees accurately time cooperation relationship, improves synchronous refresh display effect.
Embodiment 2:
As the optimization to above-described embodiment, the LED light group includes red LED lamp, green light LED lamp and blue LED lamp,
LED drive chip sets three driving ends and is separately connected red LED lamp, green light LED lamp and blue LED lamp.As shown in figure 3, LED drives
Dynamic chip is equipped with VDD, GND, SDI, SDO, CKI, CKO, OUTR, OUTG and OUTB interface, the VDD interface and GND interface point
Not Wei LED drive chip power access end and ground terminal, the SDI interface and CKI interface are respectively data/address bus and clock
The incoming end of bus, the SDO interface and CKO interface are respectively the end that picks out of data/address bus and clock bus, the OUTR,
OUTG and OUTB interface is respectively used to connection red LED lamp, green light LED lamp and blue LED lamp.The field effect transistor is equipped with
Three, the grid of three field effect transistors is all connected with drive control module (i.e. DRV in Fig. 2), source grounding, drain electrode point
It Lian Jie not OUTR, OUTG and OUTB interface.It is in application, each interface of LED drive chip is defined as follows shown in table:
The three primary colors being made up of OUTR, OUTG and OUTB output driving red LED lamp, green light LED lamp and blue LED lamp
Lamp group, to complete the luminous cascade Mach-Zehnder interferometer of colour dot lattice.SDI interface and CKI interface dock decoder module (i.e. in Fig. 2 respectively
DECODE) input terminal, for drive control data and clock referring to the input of data, SDO interface and CKO interface dock solution respectively
Code module (i.e. DECODE in Fig. 2) output end, the output for next cascade drive control data and clock reference data.
Embodiment 3:
As the optimization to above-described embodiment, the drive control module (i.e. DRV in Fig. 2) is modulated equipped with pulse width
Unit, pwm unit are connect with each field effect transistor, with this realize to the LED light of each colour light source it is efficient,
Subtly gray scale is adjusted.LED drive chip is in the data flow for receiving peripheral control unit or the transmission of upper level LED drive chip
Afterwards, decoder module (i.e. DECODE in Fig. 2) extracts the data of this grade of RGB lamp, data processing module (i.e. MCU in Fig. 2) root
Data determine the gray scale of each lamp of RGB accordingly, square with constant current pulsewidth modulation (PWM) by drive control module (i.e. DRV in Fig. 2)
Formula driving RGB lamp realizes different color blending effects.Gray scale i.e. so-called color range or grayscale, refer to the bright-dark degree of brightness.
The tonal gradation of LED display is higher, and color is abundanter, and color is more gorgeous；Conversely, display color is single, variation is simple.Due to
LED is linear unit, different from the non-linear display characteristic of traditional monitor.In order to which LED display effect can be met
Tonal gradation is not lost again simultaneously in traditional data source, and the nonlinear transformation of gradation data can be generally done in LED display system rear class,
Transformed data bits will increase.There are two types of general LED gray scale adjustment control methods: one is the electric currents that change is flowed through；
One is pulse width modulation.Change the electric current for flowing through LED, general LED pipe allows continuous work electric current at 20 milliamperes or so, removes
Red LED has outside saturated phenomenon, other LED gray scales are substantially proportional to the electric current flowed through.Another method is to utilize people
The visual persistence of eye, gray-scale Control, that is, periodically-varied light impulse length is realized with pulsewidth modulation (PWM) method, i.e.,
Duty ratio, as long as this is repeated, the period lighted is short enough, i.e., refreshing frequency is sufficiently high, and human eye is that imperceptible light-emitting pixels exist
Shake.Since pulsewidth modulation is more suitable for digital control, thus generally use microcomputer provide LED show content today,
Almost all of LED screen is all to control tonal gradation using pulsewidth modulation.Pulsewidth modulation (PWM) basic principle: pulsewidth tune
Make (PWM) basic principle: control mode is exactly to control the on-off of inverter circuit switching device, and output end is made to obtain a system
The equal pulse of column amplitude replaces sine wave or required waveform with these pulses.Namely at half of output waveform
Multiple pulses are generated in period, and the equal threshold voltages of each pulse is made to be positive string waveform, output smoothing obtained and low-order harmonic is few.
The width of each pulse is modulated by certain rule, the size of inverter circuit output voltage both can be changed, also can be changed defeated
Frequency out.Pulse width modulation (PWM) is that a kind of pair of analog signal level carries out digitally coded method.Pass through high-resolution meter
The use of number device, the duty ratio of square wave is modulated to be encoded for the level to a physical simulation signal.Pwm signal is still
It is digital, because at given any moment, the direct current supply of full amplitude or has (ON) completely or entirely without (OFF).
Voltage or current source are to be added to what fictitious load got on the repetition pulse sequence of a kind of logical (ON) or disconnected (OFF).When logical
When time is that direct current supply is added in load, when being that power supply is disconnected when disconnected.As long as bandwidth is enough, appoint
What analogue value can use PWM to be encoded.
Embodiment 4:
As the optimization to above-described embodiment, LED drive chip electric parameter (referring to Ta=25 DEG C) is arranged such as following table institute
Show:
Maximum rating (referring to Ta=25 DEG C) is as follows:
| Parameter | Symbol | Range | Unit |
| Supply voltage | VDD | - 0.5~5.5 | V |
| Logic input voltage | VI | - 0.3~VDD+0.3 | V |
| R/G/B exports electric current | IOUT | 17 | mA |
| Operating temperature | Topt | 0~+70 | ℃ |
| Storage temperature | Tstg | - 50~+125 | ℃ |
| ESD pressure resistance (HBM) | VESD | 2K | V |
LED drive chip uses dual-wire communications agreement, input agreement waveform N number of chip as shown in figure 4, two wire protocol is connected
SDI data are as follows:
Wherein, display data byte is as follows:
| 111 | 5 brightness adjustments | 8 blue lamp data | 8 green light data | 8 red light data |
Start byte are as follows:
| 0000 0000 | 0000 0000 | 0000 0000 | 0000 0000 |
End byte are as follows:
| 1111 1111 | 1111 1111 | 1111 1111 | 1111 1111 |
256 grades of gray scales are adjustable, table specific as follows:
Agreement brightness adjustment (32 grades of 5Bit) is as follows:
Main feature when specific implementation:
Electric current is promoted to by constant current scheme before to change with voltage linear；
PWM refreshing frequency is promoted to 27KHz；
Transmission speed 30MHZ；
Default powers on not bright light；
Zero-power when bright light and no data do not input.
The present invention is not limited to above-mentioned optional embodiment, anyone can show that other are each under the inspiration of the present invention
The product of kind form.Above-mentioned specific embodiment should not be understood the limitation of pairs of protection scope of the present invention, protection of the invention
Range should be subject to be defined in claims, and specification can be used for interpreting the claims.
Claims (9)
1. a kind of two-wire cascades LED drive circuit, it is characterised in that: drive core including data/address bus, clock bus and several LED
Piece, the LED drive chip carry out two-wire cascade by data/address bus and clock bus, and the data/address bus is used to drive for LED
Dynamic chip provides drive control data, and clock bus is used to provide clock for LED drive chip referring to data, the LED driving
The driving end of chip is connected with LED light group, and the LED light group includes the LED light of several capable of emitting different colored light sources.
2. a kind of two-wire according to claim 1 cascades LED drive circuit, it is characterised in that: the LED drive chip packet
Decoder module, data processing module, oscillator module, drive control module, IBIAS module and several field effect transistors are included,
The decoder module is docked with data/address bus and clock bus, is solved for the data to data/address bus and clock bus transmission
Code, and decoded data are reached into data processing module, meanwhile, decoder module is also used to will be on data/address bus and clock bus
Remaining data flow shaping respectively, and it is transmitted to next cascade LED drive chip, the oscillator module is data processing
Module provides internal reference source, and the data processing module is used to send drive control order to drive control module,
The IBIAS module is used to provide bias current to drive control module, and the drive control module is used for through field-effect crystalline substance
Body pipe output driving controls electric current, and each field effect transistor output end connects the LED light of a corresponding color light source.
3. a kind of two-wire according to claim 2 cascades LED drive circuit, it is characterised in that: the LED light group includes red
Light LED light, green light LED lamp and blue LED lamp, LED drive chip set three driving ends and are separately connected red LED lamp, green light LED
Lamp and blue LED lamp.
4. a kind of two-wire according to claim 3 cascades LED drive circuit, it is characterised in that: the LED drive chip is set
There are VDD, GND, SDI, SDO, CKI, CKO, OUTR, OUTG and OUTB interface, the VDD interface and GND interface are respectively that LED drives
The power access end and ground terminal of dynamic chip, the SDI interface and CKI interface are respectively the access of data/address bus and clock bus
End, the SDO interface and CKO interface are respectively that data/address bus and clock bus pick out end, and described OUTR, OUTG and OUTB connect
Mouth is respectively used to connection red LED lamp, green light LED lamp and blue LED lamp.
5. a kind of two-wire according to claim 4 cascades LED drive circuit, it is characterised in that: the field effect transistor
If there are three, the grid of three field effect transistors is all connected with drive control module, source grounding, and drain electrode is separately connected
OUTR, OUTG and OUTB interface.
6. a kind of two-wire according to claim 4 cascades LED drive circuit, it is characterised in that: the LED drive chip is logical
Cross VDD interface access 5V supply voltage.
7. a kind of two-wire according to claim 2 cascades LED drive circuit, it is characterised in that: the drive control module
Equipped with pwm unit, pwm unit is connect with each field effect transistor.
8. a kind of two-wire according to claim 2 cascades LED drive circuit, it is characterised in that: the oscillator module choosing
With built-in RC oscillator.
9. a kind of two-wire according to claim 1 cascades LED drive circuit, it is characterised in that: the data/address bus and when
The initial end of clock bus is connected with peripheral control unit, and the peripheral control unit is used to distinguish by data/address bus and clock bus defeated
Drive control data and clock are referring to data out.
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| CN201910791946.7A CN110415641A (en) | 2019-08-26 | 2019-08-26 | A kind of two-wire cascade LED drive circuit |
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| CN201910791946.7A CN110415641A (en) | 2019-08-26 | 2019-08-26 | A kind of two-wire cascade LED drive circuit |
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| CN201910791946.7A Pending CN110415641A (en) | 2019-08-26 | 2019-08-26 | A kind of two-wire cascade LED drive circuit |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112885293A (en) * | 2021-01-27 | 2021-06-01 | 深圳市帝麦德斯科技有限公司 | Three-channel LED display unit with built-in driving chip and display module |
| CN113473669A (en) * | 2020-03-30 | 2021-10-01 | 深圳市明微电子股份有限公司 | Double-line protocol read-write control chip, system and method |
| WO2023093138A1 (en) * | 2021-11-26 | 2023-06-01 | 海信视像科技股份有限公司 | Backlight module and display device |
| TWI810620B (en) * | 2020-07-29 | 2023-08-01 | 聯詠科技股份有限公司 | Light-emitting diode driver and light-emitting diode driving device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101521982A (en) * | 2009-04-02 | 2009-09-02 | 北京中庆微数字设备开发有限公司 | PCB board, mould, LED display device and preparing methods thereof |
| CN202025755U (en) * | 2011-03-24 | 2011-11-02 | 上海得倍电子技术有限公司 | LED chip and display device both packaged by drive circuit in hybrid manner |
| CN202189783U (en) * | 2011-03-24 | 2012-04-11 | 上海得倍电子技术有限公司 | Lamp-driver combined cylindrical RGB full-color LED hybrid packaging structure |
-
2019
- 2019-08-26 CN CN201910791946.7A patent/CN110415641A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101521982A (en) * | 2009-04-02 | 2009-09-02 | 北京中庆微数字设备开发有限公司 | PCB board, mould, LED display device and preparing methods thereof |
| CN202025755U (en) * | 2011-03-24 | 2011-11-02 | 上海得倍电子技术有限公司 | LED chip and display device both packaged by drive circuit in hybrid manner |
| CN202189783U (en) * | 2011-03-24 | 2012-04-11 | 上海得倍电子技术有限公司 | Lamp-driver combined cylindrical RGB full-color LED hybrid packaging structure |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113473669A (en) * | 2020-03-30 | 2021-10-01 | 深圳市明微电子股份有限公司 | Double-line protocol read-write control chip, system and method |
| WO2021196902A1 (en) * | 2020-03-30 | 2021-10-07 | 深圳市明微电子股份有限公司 | Dual-line protocol read-write control chip, system and method |
| CN113473669B (en) * | 2020-03-30 | 2022-05-13 | 深圳市明微电子股份有限公司 | Double-line protocol read-write control chip, system and method |
| TWI810620B (en) * | 2020-07-29 | 2023-08-01 | 聯詠科技股份有限公司 | Light-emitting diode driver and light-emitting diode driving device |
| CN112885293A (en) * | 2021-01-27 | 2021-06-01 | 深圳市帝麦德斯科技有限公司 | Three-channel LED display unit with built-in driving chip and display module |
| WO2023093138A1 (en) * | 2021-11-26 | 2023-06-01 | 海信视像科技股份有限公司 | Backlight module and display device |
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