Test Setup and Measurements

The test setup for appliance LED Fade-in Fade-out with GPI pin follows:

To control the system without the use of software, map the GPI pin to margin high-low operation as listed in the GPI Configuration table of the DACx3701 10-Bit and 8-Bit, Voltage-Output Smart DACs With Nonvolatile Memory and PMBus™ Compatible I2C Interface With GPI Control data sheet. The rising edge of the GPI triggers the MARGIN-HIGH output voltage, supplying 20mA of current to the LED, and the falling edge triggers the MARGIN-LOW voltage, supplying 10-mA LED current. When the DAC output is in the slewing condition, any change in the GPI state changes the direction of the slew dynamically after the ongoing SLEW_RATE time, as shown in the following figure.