Review on SunFounder I2C LCD Module Shield for Arduino R3 Mega2560 - 2004 20x4 Serial TWI by Mario Portillo

Working properly; except that the backlight cannot be manually controlled as the spec says. With sweater. Unless you have a need or interest in dimming the backlight with resistors or PWM (pulse width modulation), the LCD works fine. Purchased December 2020. There have been different versions over the years using the same list. . The version I received only allows the LED backlight to be controlled via software and only OFF or ON. Without dimming. The description for the board states that the backlight is controlled by a jumper. It is not. The jumper on the backlight board labeled LED does nothing whether the jumper is on or not. two pens. The jumper is therefore always connected, regardless of whether it is set or not. I unclipped and removed the backpack from the LCD board and carefully cut the path between the two jumper pins with a razor blade. This restored the jumper function and dimmed the backlight with a PWM pin from the microcontroller, etc. If I can find a thin, sharp tool that fits between the backpack and the LCD, I can cut that pesky trace without having to desolder the backpack. The surface mount transistor next to the jumper is the driver for the LED backlight. It can turn off the base and PWM, this can also be an option.