The present application claims priority from chinese patent application CN201910832321.0 filed 2019, 9, month 4.
Disclosure of Invention
The to-be-solved technical problem of the utility model is to provide a multiunit LED switching circuit in order to overcome among the prior art that the space that a set of LED unit needs a drive circuit to cause occupies the defect big, that the wiring degree of difficulty is big and increase cost.
The utility model discloses an above-mentioned technical problem is solved through following technical scheme:
a control circuit for driving M groups of LED units, each group of LED units comprising N segments of LEDs connected in series in sequence: the first LED section, the second LED section, the N-1LED section and the NLED section, the head end of each LED unit group is the positive polarity end of the first LED section, and the tail end is the negative polarity end of the NLED section, comprising:
n linear current sources are arranged corresponding to the N segments of the LED segments, and the N linear current sources are respectively as follows: the LED driving circuit comprises a first linear current source, …, an N-1 linear current source and an Nth linear current source, wherein two ends of each linear current source are a first end and a second end respectively, the first ends of the linear current sources are connected with each other, and the second end of the Nth linear current source is connected with the tail ends of the M LED unit groups; and
n-1 diode groups correspond to the first linear current source, … and the N-1 linear current source, each diode group comprises M first diodes, the negative polarity ends of the M first diodes are connected with the second ends of the linear current sources corresponding to the diode group where the M first diodes are located, the positive polarity ends of the M first diodes are configured to be respectively connected with the negative polarity ends of the M LED segments corresponding to the linear current source, M, N are integers, M is more than or equal to 2, and N is more than or equal to 2.
A multi-group LED switching circuit comprises the control circuit;
m LED unit groups, every LED unit group includes N section series connection's LED segmentation in proper order: the LED light source comprises a first LED segment, an N-1LED segment and an NLED segment, wherein the head end of each LED unit group is a positive polarity end of the first LED segment, and the tail end of each LED unit group is a negative polarity end of the NLED segment; and
and a switch switching circuit, wherein an AC signal is configured as an input between one end and the first end, and the other end can be selectively connected with the head end of one of the M LED unit groups.
Optionally, the switch switching circuit comprises:
a stationary contact having an AC signal configured as an input to the first terminal;
m movable contacts connected to the head ends of the M LED unit groups respectively; and
and a common terminal, one end of which is connected with the fixed contact and the other end of which can be selectively connected with one of the M movable contacts.
Optionally, the switch switching circuit further comprises:
a hybrid movable contact capable of selectively communicating with the stationary contact via the common port; and
and the negative polarity ends of the M second diodes are connected with the mixed moving contacts, and the positive polarity ends of the M second diodes are correspondingly connected with the M moving contacts respectively.
Optionally, the method further comprises:
and the switch control logic circuit is connected with the switch switching circuit and is used for controlling the switching of the public end.
Optionally, the switch control logic circuit comprises:
and the signal generator is provided with a single-path or multi-path output end and is used for generating signals for controlling the on-off time of the switches of the M LED unit groups.
Optionally, the method further comprises: and the rectifying circuit is used for processing the AC signal into a DC signal and outputting the DC signal, the input end of the rectifying circuit is configured to receive the AC signal, and the output end of the rectifying circuit is respectively connected with the switch switching circuit and the public end.
Optionally, the switch switching circuit is any one of a mechanical switch, a remote control switch, a touch switch, or a combination thereof.
The utility model also provides a LED driver chip, the integration has above-mentioned control circuit.
On the basis of the common knowledge in the field, the above preferred conditions can be combined at will to obtain the preferred embodiments of the present invention.
The utility model discloses an actively advance the effect and lie in: the LED unit groups are switched by the switch switching circuit so that the plurality of LED unit groups share one driving circuit, thereby greatly saving the occupied space of an aluminum plate and reducing the wiring difficulty and the circuit cost; the diode connected in series between the cathode of the LED in the LED unit group and the anode of the linear current source blocks a discharge loop, so that the LED in the LED unit group with the disconnected anode does not have current to flow and does not light, and the thorough switching of the multiple groups of LEDs is realized; the mixed moving contact is further connected with the LED unit groups connected with the diodes of the common anode, so that the mixed color light effect of the LED unit groups is realized, the grouping control function of the LED unit groups is not influenced, the combination of multiple functions of the LED unit groups is realized, and the LED unit groups are not influenced mutually; and further, the common end of the switch switching circuit is controlled by one switch control logic circuit, so that the color mixing light effect of different proportions of a plurality of groups of LED unit groups is realized.
Detailed Description
The present invention is further illustrated by way of the following examples, which are not intended to limit the scope of the invention.
Example 1
The present embodiment provides a multi-LED switching circuit, which is powered by a rectifier circuit BD1, and includes: three groups of LED units, a first group of LED units comprising LED segment 11, LED segment 12.. LED segment 1N, a second group of LED units comprising LED segment 21, LED segment 22.. LED segment 2N, and a third group of LED units comprising LED segment 31, LED segment 32.. LED segment 3N.
The number of the series-connected LEDs of each segment can be distributed as long as the design requirements of the LED driving chip IC1 are met (the LED driving chips of various merchants meet parameters in the aspects of harmonic waves, surges and the like, and the string ratio of the used LED segments is recommended).
Control circuit 01, is used for driving three LED unit groups, includes: three linear current sources, which are arranged corresponding to the N segments of the LED segments, are respectively: the LED driving circuit comprises first linear current sources I1 and …, an N-1 linear current source IN-1 and an Nth linear current source IN, wherein two ends of each linear current source are a first end and a second end respectively, the first ends of the linear current sources are connected with each other, and the second end of the Nth linear current source IN-1 is connected with the tail ends of three LED unit groups;
n-1 diode groups corresponding to the first linear current sources I1 and … and the (N-1) th linear current source IN-1, wherein each diode group comprises three first diodes, the negative polarity ends of the three first diodes are connected with the second ends of the linear current sources corresponding to the diode group IN which the three first diodes are arranged, and the positive polarity ends of the three first diodes are configured to be respectively connected with the negative polarity ends of the three LED segments corresponding to the linear current sources; and
and a switch switching circuit SW having one end and a first end between which an AC signal is provided as an input and the other end capable of being selectively connected to a head end of one of the three LED cell groups.
Specifically, referring to fig. 1, the diode group corresponding to the first linear current source I1 includes a first diode D11, a first diode D12 and a first diode D13, anodes of the first diode D11, the first diode D12 and the first diode D13 are respectively connected to negative terminals of the LED segment 11, the LED segment 21 and the LED segment 31, cathodes of the first diode D11, the first diode D12 and the first diode D13 are all connected to positive terminals of the first linear current source I1, and the diode group corresponding to the N-1 linear current source IN-1 includes a first diode DN-1, a first diode DN-1,2 and a first diode DN-1,3, and connection relationship thereof can be derived from a diode corresponding to the first linear current source I1, which is not described herein.
Wherein N is an integer greater than 1.
It should be noted that in this embodiment, three groups of LED units are taken as an example, in other embodiments not shown, two groups, four groups, or more groups of LED units may also be used, and details are not repeated here.
The input end of the rectifier circuit BD1 is connected to a power supply, and converts the power supply into direct current. The positive output end of the rectifying circuit BD1 is connected with the common end of the switch switching circuit SW, and a plurality of movable contacts of the switch switching circuit SW are respectively connected with the positive electrode of each LED unit group and used for switching the LED unit groups.
As shown IN fig. 1, when the common terminal of the switch switching circuit SW is switched to be connected with the movable contact a, the first LED unit group is connected to the power supply, and the LED segment 11 and the LED segment 12.. the LED segment 1N are respectively controlled by the linear current sources I1 and I2.. IN, and the LEDs IN the LED segments IN the first LED unit group are all turned on; at this time, the first diodes D12, D22.. DN-1,2 connected in series between the negative electrode of the last LED in each LED segment of the second LED unit group and the linear current source block the discharge circuit of each LED segment of the first LED unit group, so that the positive electrode of the first LED of each LED segment of the second LED unit group has no voltage, and therefore, no current flows through the LEDs in each segment of the second LED unit group, and the LEDs in the third LED unit group will not be turned on. Similarly, when the common end of the switch switching circuit SW1 is switched to be connected with the moving contact b, the LEDs in the second LED unit group are all turned on, and the LEDs in the first LED unit group and the third LED unit group do not have current flowing and cannot be turned on, so that a driving chip shared by multiple groups of LEDs is realized, and meanwhile, each LED unit group is thoroughly switched without mutual influence, and free switching of monochromatic light of each group can be realized.
In the embodiment, the LED unit groups are switched by the switch switching circuit so that the plurality of LED unit groups share one driving circuit, thereby greatly saving the occupied space of an aluminum plate and reducing the wiring difficulty and the circuit cost; the diode connected in series between the cathode of the LED in the LED unit group and the anode of the linear current source blocks a discharge loop, so that the LED in the LED unit group with the disconnected anode does not have current to flow and does not light, and the thorough switching of the multiple groups of LED unit groups is realized.
The embodiment also provides an LED driving chip integrated with the control circuit 01.
Example 2
In this embodiment, a lighting circuit of mixed color light is added to embodiment 1. As shown in fig. 2, based on the circuit diagram of embodiment 1, the switch switching circuit SW further includes a mixed moving contact D and a plurality of second diodes (the present embodiment is also exemplified by three groups of LED units, so there are second diodes D1, D2 and D3), the anodes of the second diodes D1, D2 and D3 are connected together and connected to the mixed moving contact D, and the cathodes of the second diodes D1, D2 and D3 are connected to the anodes of the first, second and third groups of LED units, respectively.
When the common end of the switch switching circuit SW is switched to be connected with the hybrid contact D, the first, second and third LED unit groups are connected to a power supply through the second diodes D1, D2 and D3 which are conducted IN the forward direction, the linear current sources I1 and I2.. IN of the LED driving chip IC1 supply current to the LEDs of each segment, and the LEDs IN the first, second and third LED unit groups are current-equalized and overcurrent and are all lighted, that is, the LEDs of various color temperatures are lighted together, so as to generate a color mixing light effect.
When the common terminal of the switch switching circuit SW is switched to another movable contact (such as a, b or c, where the movable contact a is taken as an example for description), only the first LED unit group connected to the movable contact a connected to the common terminal is connected to the power supply, and the LEDs in each segment in the first LED unit group are turned on to emit monochromatic light of a certain color temperature. At this time, although the second LED unit group is connected to the first LED unit group through the second diode D2, the second diode D2 is turned off in the reverse direction with respect to the second LED unit group, the current flowing through the first LED unit group cannot flow into the second LED unit group through the second diode D2, and no current flows through the LEDs in each segment in the second LED unit group, and thus the LEDs cannot be turned on; similarly, the LEDs in each segment in the third LED unit group cannot be lit. When the common end of the switch switching circuit SW is switched to other movable contacts, the second diodes D1, D2 and D3 also play an isolation role, and the circuit presents the effect of monochromatic light.
On the basis of embodiment 1, the mixed color light effect of the multiple groups of LED units is realized by connecting the mixed moving contact with the multiple LED units connected by the multiple diodes of the common anode, and the group control function of the multiple groups of LED units is not affected, so that the combination of multiple functions of the multiple groups of LED units is realized, and simultaneously, the functions of the multiple groups of LED units are not affected each other.
Example 3
On the basis of embodiment 1, the present embodiment realizes the effect of color mixing light in different proportions. As shown in fig. 3, on the basis of the circuit schematic diagram of embodiment 1, the multi-group LED switching circuit further includes a switch control logic circuit for controlling the switching of the common terminal of the switch switching circuit; the switch control logic circuit comprises a signal generator with single-path or multi-path output and is used for generating signals to control the switch conduction time of the LED unit groups.
The switch switching circuit can comprise a plurality of public ends, a single-path or multi-path signal generator in the switch control logic circuit outputs a single-path or multi-path signal for controlling each public end of the switch switching circuit to switch among different movable contacts according to different time ratios, and the signal controls the switch conduction time of each group of LED unit groups to be different in a certain time, so that the lighting time of each group of LED unit groups is different, and a plurality of groups of LED unit groups obtain power with different ratios, thereby obtaining various random or artificially set color temperatures, forming different light color mixtures and generating mixed color effects with different ratios.
In this embodiment, on the basis of embodiment 1, the common end of the switch switching circuit is controlled by one switch control logic circuit, and the switch on time of each LED unit group is controlled to make the lighting time of each group of light color LEDs different, thereby achieving the effect of color mixing of multiple groups of LED unit groups in different proportions.
Although specific embodiments of the present invention have been described above, it will be understood by those skilled in the art that this is by way of example only and that the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and the principles of the present invention, and these changes and modifications are all within the scope of the present invention.