ZHCSLO5B December 2020 – December 2021 LM25149
PRODUCTION DATA
The LM25149 operates with peak current-mode control such that the compensation voltage is proportional to the peak inductor current. During no-load or light-load conditions, the output capacitor discharges very slowly. As a result, the compensation voltage does not demand the driver output pulses on a cycle-by-cycle basis. When the LM25149 controller detects 16 missed switching cycles, it enters sleep mode and switches to a low IQ state to reduce the current drawn from the input. For the LM25149 to go into sleep mode, the controller must be programmed for diode emulation (tie PFM/SYNC to VDDA).
The typical controller IQ in sleep mode is 9.5 μA with a 3.3-V output.