The PCA9532 is a 16-bit I2C-bus and SMBus I/O expander optimized for dimming LEDs in256 discrete steps for Red/Green/Blue (RGB) color mixing and back light applications.The PCA9532 contains an internal oscillator with two user programmable blink rates andduty cycles coupled to the output PWM. The LED brightness is controlled by setting theblink rate high enough (> 100 Hz) that the blinking cannot be seen and then using the dutycycle to vary the amount of time the LED is on and thus the average current through the LED.


  • Input Power
  • 100-240VAC 50/60hz
  • Output power
  • 10A-120watts per channel @12V
  • 10A-240watts per channel @24V


  • 256 brightness steps
  • Input/outputs not used as LED drivers can be used as regular GPIOs
  • Internal oscillator requires no external components
  • I2C-bus interface logic compatible with SMBus
  • Internal power-on reset
  • 16 LED drivers (on, off, flashing at a programmable rate)
  • Two selectable, fully programmable blink rates (frequency and duty cycle) between
  • 0.591 Hz and 152 Hz (1.69 second and 6.58 milliseconds)


  • Backlighting
  • RGB Color Mixing
  • Sensors Control
  • Power Switches, Push−buttons
  • Alarm Systems

LED0 to LED15: LED Driver Outputs / General Purpose I/Os:

                     The pins are open drain outputs used to drive directly LEDs. Any of these pins can be programmed to drive the LED ON, OFF, Blink Rate1 or Blink Rate2. When not used for controlling the LEDs, these pins may be used as general purpose parallel input/output.