7.4.3 Active Mode
The LM76002/LM76003 is in active mode when the EN pin and UVLO high threshold levels are satisfied. The simplest way to enable the operation of the LM76002/LM76003 is to connect the EN pin to VIN, which allows self start-up of the LM76002/LM76003 when the input voltage is in the operation range: 3.5 V to 60 V. See Enable (EN Pin) and UVLO for details on setting these operating levels.
In active mode, depending on the load current, the LM76002/LM76003 will be in one of five sub modes:
- CCM with fixed switching frequency with load between half of IMINPK to full load.
- DCM when the load current is lower than half of the inductor current ripple.
- Light load mode where the device uses pulse frequency modulation (PFM) and lowers the switching frequency at load under half of IMINPK to improve efficiency.
- Foldback mode when switching frequency is reduced to maintain output regulation with supply voltages that cause the minimum tON or tOFF to be exceeded.
- Forced-pulse-width modulation (FPWM) is similar to CCM with fixed switching frequency, but extends the fixed frequency range of operation from full to no load.