The LMR60460-Q1 is in
an active mode whenever the EN pin voltage has risen above
VEN-TH(R), the input voltage exceeds
VINUVLO(R), and no other fault conditions are
present. The simplest way to enable the LMR60460-Q1 is to connect the EN pin to VIN, which
allows self start-up when the applied input voltage exceeds the
VINUVLO(R).
In active mode, the LMR60460-Q1 is in one of the
following modes:
- Continuous conduction mode (CCM) with fixed switching frequency when the
load current is above half of the inductor current ripple
- Auto mode - light load operation: pulse frequency
modulation (PFM) where switching frequency is
reduced at light load
- FPWM mode - light load operation: CCM mode when the load current is lower
than half of the inductor current ripple
- Minimum on time: at high input voltage and low
output voltages, the switching frequency is reduced
to maintain regulation
- Dropout mode: when switching frequency is reduced
to minimize voltage dropout between input and
output