SNVS852D June 2012 – August 2018 LMZ20502
In forced PWM mode, the converter operates as a constant frequency voltage mode regulator with input voltage feed-forward. This provides excellent line and load regulation and low output voltage ripple. This operation is maintained, even at no-load, by allowing the inductor current to reverse its normal direction. While in PWM mode, the output voltage is regulated by switching at a constant frequency and modulating the duty cycle to control the power to the load. This mode trades off reduced light load efficiency for low output voltage ripple and constant switching frequency. In this mode, a negative current limit of about 750mA is imposed to prevent damage to the regulator power FETs.