ZHCS901E May 2012 – September 2021 TPS55340
PRODUCTION DATA
The device is designed to operate in high-efficiency, pulse-skipping mode under light load conditions. Discontinuous-conduction-mode (DCM) operation initiates when the switch current falls to 0 A. During DCM operation, the catch diode stops conducting when the switch current falls to 0 A. The switching node (the SW pin) waveform takes on the characteristics of DCM operation as shown in Figure 8-6. As the load decreases further and when the voltage-regulation loop of TPS55340 device requires an on-time pulse width less than the minimum PWM pulse width of 77 ns (typical), the IC enters pulse-skipping mode. In this mode, the device holds the power switch off for several switching cycles to prevent the output voltage from rising too much above the desired regulated voltage.