The PCA9536 is a general purpose 4-Channel digital I/O controller. In this design, we dedicated the last GPIO (GPIO.3) to a buzzer for alarm notification applications. The remaining three GPIO pins are available for user applications. The address of the PCA9536 is fixed at 0x64, so only one of these devices may be attached to a single I²C port. The PCA9536 has the ability to source up to 85ma of current, not to exceed 50ma per GPIO, which is more than twice the rating of many similar devices we have worked with. The unusually high current delivery per output makes the PCA9536 ideal for driving LEDs, buzzers, and other small circuits without the need for specialized switching circuitry.
All I²C Mini Modules are designed to operate at 5VDC. Using a convenient 4-Pin plug, devices can be daisy chained onto the I²C Bus, eliminating the need for soldering. Simply plug together the devices you need for your next automation application. If you are wiring in your own I²C port, on-board 4.7K jumper-selectable pull-up resistors are available for convenience purposes.