Hello, everyone.

I would like to confirm how to use ADP5585.

Can ADP5585 use key matrix function and GPIO function and PWM control function at the same moment?

GPIO function is for LED backlight enable/disable.

And PWM control function is for LED backlight brightness control.

Best regards, S.Okudera

  • 0
    •  Analog Employees 
    on Dec 9, 2013 11:08 PM

    Hello S. Okudera,

    Each of the ADP5585 pins can be independently set to operate in GPIO or keypad modes. The PWM mode is a special mode of the R4 pin. With the PWM mode selected, the maximum keypad matrix rows will be reduced by one, but the other pins can be used in a keypad matrix.

    Additionally, any other Row or Column pin can be set to either GPIO or keypad mode, but selecting more GPIO pins reduced the keypad matrix again. Each pin must select between GPIO or keypad.

    For example, in order to produce a PWM signal, a single GPIO signal, and the largest keypad matrix available with those two pins used:

    R3 is set to PWM

    C4 is set to GPIO 11

    R0-2, R4, C0-C3 are set to KP mode

    This results in 1 GPIO, 1 PWM, and a 4x4 keypad matrix allowing up to 16 keypads.

    If more keys are needed, the ADP5585 has a -01 option that has one more row pin, allowing for a 5x4 matrix, with 20 keypads.

    If more PWMs are needed, please look at the ADP5586. This is a similar keypad controller that has some advanced PWM functionality, and one more PWM. The ADP5586 excels in providing indicator LED timings, off loading the timing burden from the microcontoller.

    Please let me know if you have any more questions,