JAJSDZ5 October 2017 LM2623-Q1
PRODUCTION DATA.
In the LM2623-Q1 device boost circuit the Schottky diode is in the path of the inductor current discharge. As a result the Schottky diode detects a high-current step from 0 A to the peak inductor current each time the switch turns off, and the diode turns on. Any inductance in series with the diode causes a voltage spike at SW. This can potentially overvoltage the SW pin, or feed through to VOUT and through the output capacitor, into GND. Connecting the anode of the diode as close as possible to the SW pin, and connecting the cathode of the diode as close as possible to COUT reduces the parasitic inductance and minimizes these voltage spikes.