The diagram shown on this slide provides a look at how load step affects operation of the LinkZero-AX device in this 1.5 W, non-isolated design. If this circuit experiences a large step-up load, the output voltage will momentarily droop as current is provided from the output capacitor while the switching duty cycle increases to meet demand. The LinkZero-AX device continues to receive feedback during this entire process, so there is no problem. If this circuit experiences a step-down load, the output voltage will rise, cutting off feedback until the excess energy on the output capacitor is discharged by the load. Remember from the previous slides, if the LinkZero-AX device doesn’t get feedback for more than 160 switching cycles (approximately 2.5 mS) it will go into the off-mode, causing an unwanted shutdown. To prevent this from happening, it is necessary to shorten the time to recover from a step-down load. First, add a small resistor across the output to quickly discharge the output capacitor after a voltage swell. This resistor should be sized to draw about 1% of full load current. Be sure to include the load drawn by feedback resistors R9 and R3 when calculating full load current. Next, the feedback circuit response can be increased to a rising output voltage by adding a capacitor in parallel with R9, the upper feedback resistor. This allows the signal to temporarily bypass R9 during a fast output voltage transition, reducing the feedback loop response time and limiting output voltage rise.