LED Capacitive Touch Dimmer PWM Control Board

Description

LED Capacitive Touch Dimmer PWM Control Board

Functional characteristics

touch dimming module can realize the touch switch control and brightness adjustment of LED lights. Has the following functional characteristics and advantages:

⒈The brightness of the light can be adjusted freely according to the needs, the selection range is wide, and the operation is simple and convenient. 

⒉  may have medium to realize the touch function (such as glass, acrylic, plastic, ceramic, etc.) isolation protection, the safe.

⒊The application voltage range is wide, which can be arbitrarily selected between 2.4~4.5V . 

⒋  Simple application circuit, few peripheral devices, convenient processing and low cost.

⒌Good resistance to power interference and mobile phone interference. EFT can reach more than ± 2KV ; in the case of close-range, multi-angle mobile phone interference, 

Touch response sensitivity and reliability are not affected.

      6. Installation: There is no need to directly contact the copper foil, and it can be dimmed through acrylic glass or plastic of more than 3mm.

   7. Uses: Can control LED modules, light strips and other products. Suitable for indoor table lamp, LED lighting dimming, DIY car lamp dimming modification best accessories.

   8. Function: single-line touch, using the principle of capacitive touch, sensitive and sensitive touch. The default is the LED touch stepless dimming function with switch function, dimming function, and brightness memory fades in and out. Slowly brighten when turning on the light, and slowly darken when turning off the light, effectively avoiding eye irritation.

   9. Dimming mode: stepless PWM dimming

   10. Wiring method: (VCC, GND) in the PCB board is the power input, (LED+, LED-) is connected to the positive and negative level of the LED lamp (fingerprint) is connected to the touch area, and it can also be led out by wiring (note that the wiring should not be too long, the outlet Later, it is recommended to use a small copper skin as the induction area), the copper skin area is recommended to be about 2x3cm. The copper foil module on the board attaches the copper foil to the side of the housing.

   11. How to use

   a) When you click and touch (touch duration is less than 550ms), you can control the lighting. One click to touch, the light is on; another click to touch, the light is off. The initial brightness of the lighting is fixed at 90% of full brightness.

   b) When long press the touch (the touch duration is greater than 550ms), stepless brightness adjustment of the light can be achieved. Once long touch, the light brightness gradually increases. When released, the light brightness stops at the corresponding brightness at the moment of release. If the long press time exceeds 3 seconds, the light brightness will not change after reaching the maximum brightness; press and hold again, light brightness gradually decreases, light levels when released in the release stop time corresponding to the luminance, if a long time over 3 seconds, the light intensity is no longer reaches the minimum brightness variation
of. This cycle.

   12. Debugging tips

   If there is a false trigger or no trigger during debugging, it may be caused by the following reasons:

   a ) The touch line is too thick

   b ) The touch line is too long

   c ) Copper skin is not big enough

   d ) Disturbed near the end of the switching power supply

   e ) Touch parameter C1 is unreasonable

 

 

 

Technical characteristics

◆ TI touch input corresponds to LED light control output. There are four functions available, input by T1 and T2 pins before power on

State to decide. details as follows:

⒈ T1=1 , T2=1 correspondence: LED touch stepless dimming function without brightness memory  

⒉  T1=0 , T2=1 correspondence: LED touch stepless dimming function without brightness memory 

⒊ T1=1 , T2=0 corresponding: LED touch stepless dimming function with brightness memory fades in and fades out  

⒋  T1=0 , T2=0 corresponds to: LED three-segment touch dimming function 

 

◆The stepless dimming function of LED touch without brightness memory is bright and dark as follows:

△When the power is initially turned on, the light is off.

△When the touch is touched (touch duration is less than 550ms ), the light can be turned on and off. One click to touch, the light is on; another click to touch, the light is off. This cycle. There is no brightness buffer when the light is on or off. And the initial brightness of the light is fixed at 50% of the full brightness.

△When you press and hold the touch (the touch duration is greater than 550ms), you can achieve stepless brightness adjustment of the light. Once long touch, the light brightness gradually increases. When released, the light brightness stops at the corresponding brightness at the time of release. If the long press time exceeds 3 seconds, the light brightness will not change after reaching the maximum brightness; long touch again, the brightness of the light gradually decreases. When it is released, the brightness of the light stops at the corresponding brightness at the moment of release. If the long press time exceeds 3 seconds, the light brightness will not change after reaching the minimum brightness. This cycle.

△ Tap touch and long touch can be used at any time, and the functions between each other are not interfered and restricted.

◆The stepless dimming function of LED touch without brightness memory fades in and out. It is based on the stepless dimming function of LED touch without brightness memory. Slowly and smoothly transition the light from a lower brightness to the initial brightness when the light is turned on. When you click and touch to turn off the light, the light is slowly and smoothly reduced from the current brightness until it is turned off, so as to achieve the visual buffer effect of slowly changing brightness and protect the eyes and the effect of vision.

◆The stepless dimming function of LED touch with brightness memory fades in and out is the addition of the stepless dimming function of LED touch without brightness memory. That is to say, when the power supply is uninterrupted, the brightness will be memorized every time you touch and turn off the light, and the brightness will be used as the initial brightness when you click and turn on the light next time. In the case of power failure, the first click after turning on the power again turns on the light, and the initial brightness is fixed at 50% of full brightness.

◆ LED three-stage touch dimming function

△When the power is initially turned on, the light is off. 

△ Each time you click and touch, the brightness of the light changes in turn according to low brightness → medium brightness → high brightness → off.  

Sensitivity adjustment

The larger the capacitance value, the higher the sensitivity; the smaller the capacitance value, the lower the sensitivity.

Refer to the table below to adjust the touch sensitivity:

Media type	Capacitor type	Capacitance parameters
Directly touch the metal shell	Polyester capacitor	333	0.033uF/25V
Acrylic glass within 3mm	Polyester capacitor	103	0.01uF/25V
3-6mm acrylic glass	Polyester capacitor	203	0.02uF/25V
6-10mm acrylic glass	Polyester capacitor	473	0.047uF/25V

 

 

Note: When the output of the constant voltage dimmer is connected to the LED, the upper limit current resistor must be connected in series!

Calculation method of current limiting resistance: R =  ( Vi-Vled ) / Io

Among them, Vi is the input voltage, Vled is the total voltage drop of all LED lamps, Io is the total current of the lamp string. The floating range of Vi and Vled should be considered in the calculation. Generally, Vi will be larger when the battery is fully charged. After the LED heats up, Vled will drop! Prevent overcurrent from burning the module or lamp beads.