JAJSPC8C December 2022 – February 2024 TPSM33615 , TPSM33625
PRODUCTION DATA
Diode emulation prevents reverse current through the inductor which potentially requires a lower frequency needed to regulate given a fixed peak inductor current. Diode emulation also limits ripple current as frequency is reduced. With a fixed peak current, as output current is reduced to zero, frequency must be reduced to near zero to maintain regulation.
The TPSM336x5 has a minimum peak inductor current setting (see IPEAKMIN in Section 6.5) while in auto mode. After current is reduced to a low value with fixed input voltage, on time is constant. Regulation is then achieved by adjusting frequency. This mode of operation is called PFM mode regulation.