JL7022WE touch sensing IC is an integrated circuit designed to realize human touch interface. It can replace the mechanical light touch button to realize waterproof and dustproof, sealed isolation, strong and beautiful operation interface. Using this chip can realize touch switch control and brightness adjustment of LED lights. The peripheral circuit required by the scheme is simple and easy to operate. By determining the sensitivity and selecting the capacitor, the IC can automatically overcome various interferences caused by ambient temperature, humidity, surface debris, etc., and avoid button differences caused by resistance and capacitance errors.

Basic Features

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

The output frequency of the control signal is up to 20KHz, and there is no stroboscopic phenomenon.

High sensitivity (can be adjusted by the user)

High waterproof performance

Low standby power consumption, power saving

 High anti-interference performance, touch response sensitivity and reliability are not affected in the case of close-range and multi-angle mobile phone interference

Button sensor pad size: greater than 3mm×3mm, depending on different panel materials and thicknesses, you can directly use large-area metal sheets

Button sensor pad spacing: greater than 2mm

The shape of the key sensor pad: any shape (the contact area with the panel must be guaranteed)

Key sensor pad material: PCB copper foil, metal sheet, flat top cylindrical spring, conductive rubber, conductive ink, ITO layer of conductive glass, etc.

Panel material: insulating materials, such as plexiglass, ordinary glass, tempered glass, plastic, wood, paper, ceramics, stone, etc.

Panel thickness: 0-12mm, different according to different panel materials

Working temperature: -25℃-85℃

Working voltage: 2.7V-5.5V

Package Type: SOP8

Application areas: touch desk lamps, touch key switches, etc.

Pin layout

Application Notes

A: Dimming scheme

B: Touch control scheme

EC1, C2, C3 close to IC

Note: When the difference in dielectric material and thickness is large, the touch sensitivity can be adjusted by adjusting the capacitance value of C3 sampling capacitor. The larger the capacitance value, the higher the sensitivity; the smaller the capacitance value, the lower the sensitivity.

Function description

The TI touch input corresponds to the SO light control output. By modulating the duty cycle of the PWM output signal, the on-off and brightness changes of the LED light are controlled. The frequency of the PWM signal is fixed at about 20KHz.

There are eight optional functions, which are determined by the input state of the OPT1/OPT2/OPT3 pins before power-on. details as follows:

1) OPT1 & OPT2 & OPT3 are all suspended or connected to power supply: LED touch stepless dimming without brightness memory without brightness buffer

2) OPT1 is grounded, OPT2 & OPT3 are suspended or connected to power supply: LED touch stepless dimming with brightness memory and no brightness buffer

3) OPT1 & OPT3 are suspended or connected to power supply, OPT2 is grounded: LED three-segment touch dimming, [High->Medium->Low->Off] cycle

4) OPT1 & OPT2 are grounded, OPT3 is suspended or connected to power supply: LED three-segment touch dimming, [Low->Medium->High->Off] cycle

5) OPT1 & OPT2 are suspended or connected to power supply, OPT3 is grounded: single-channel touch key, touch key output low level

6) OPT1 is suspended or connected to power supply, OPT2 & OPT3 are grounded: single-channel touch key, touch key output high level

7) OPT1 & OPT3 are grounded, OPT2 is suspended or connected to the power supply: single-key touch switch, power-on output high level

8) OPT1 & OPT2 & OPT3 grounding: single-key touch switch, power-on output low level

The LED touch stepless dimming function without brightness memory without brightness buffer is as follows:

At the initial power-on, the SO output is all low, and the LED light does not light up. Short press the touch (touch duration is less than 550ms), can realize the light switch on and off control. A short press and touch, the light is on; short press and touch again, the light is off. Short press multiple times to cycle through. There is no brightness buffer when the lights are on or off. And the brightness of each time the light is turned on is fixed to the highest brightness, and the corresponding high-level duty cycle of the output PWM signal is 100%.

Long press the touch (touch duration is greater than 550ms) to realize stepless brightness adjustment of the light. Press and hold once, the brightness of the light will gradually decrease, and stop at the current brightness when you release it. If the long-press time exceeds 3 seconds, the brightness of the light will not change after it reaches the lowest level; press and touch again, the brightness of the light will gradually increase. When you release it, it stops at the current brightness. If you press and hold for more than 3 seconds, the brightness of the light will not change after it reaches the highest level. Press and hold multiple times to cycle through. The PWM signal duty cycle is 2% for the lowest brightness and 100% for the highest brightness. When the light is off, long press and touch to turn on the light. In this case, after the button is pressed, the light will be turned on at the highest brightness first, and if it is not released after more than 550ms, it will start to stepless downward dimming. Click to touch and long-press to touch can be used at any time without interference and limitation of each other's functions.

The LED touch stepless dimming function with brightness memory without brightness buffer is the addition of brightness memory function to the LED touch stepless dimming function without brightness memory and without brightness buffer. That is to say, in the case of uninterrupted power supply, the brightness of each short press to turn off the light will be stored in memory, and the brightness will be used as the initial brightness when the light is touched next time. The direction of the first dimming after turning on the light is determined by the previously memorized brightness value. If the memorized brightness value is greater than 50%, the dimming will be downward; if the memorized brightness value is less than 50%, the dimming will be upward. After initial power-on or power-off, the initial brightness of the light is fixed at 100% maximum brightness for the first time, and the direction of the first dimming is fixed as downward dimming.

LED three-stage touch dimming, [High->Medium->Low->Off] cycle

At the initial power-on, the SO output is all low, and the LED light does not light up. The first touch, the light is high-level brightness; the second touch, the light is medium-level brightness; the third touch, the light is low-level brightness; the fourth touch, the light is off. Press multiple times and cycle through. The duty ratios of the output PWM signals corresponding to the high, medium and low brightness levels are 100%, 40%, and 10%, respectively.

LED three-stage touch dimming, [Low->Medium->High->Off] cycle

At the initial power-on, the SO output is all low, and the LED light does not light up. The first touch, the light is low-level brightness; the second touch, the light is medium-level brightness; the third touch, the light is high-level brightness; the fourth touch, the light is off. Press multiple times and cycle through. The duty ratios of the output PWM signals corresponding to the low, middle, and high brightness levels are 10%, 40%, and 100%, respectively.

Single-channel touch key, touch key output low level

After power-on, SO output high level, after touching the button, SO output low level, after releasing the touch, SO output returns to high level Single-channel touch button, touch button output high level

After power on, SO output low level, after touching the button, SO output high level, after touch release, SO output returns to low level

Single-channel touch switch, power-on output high level

Each time the button is touched, the SO output state is flipped once. After the touch is released, the SO output state remains a single-channel touch switch, and the output is low when powered on.

Each time the button is touched, the SO output state is flipped once, and after the touch is released, the SO output state remains