ZHCSLJ7A June 2021 – June 2021 LM5146
PRODUCTION DATA
The LM5146 incorporates a voltage-mode control loop implementation with input voltage feedforward to eliminate the input voltage dependence of the PWM modulator gain. This configuration allows the controller to maintain stability throughout the entire input voltage operating range and provides optimal response to input voltage transient disturbances. The constant gain provided by the controller greatly simplifies loop compensation design because the loop characteristics remain constant as the input voltage changes, unlike a buck converter without voltage feedforward. An increase in input voltage is matched by a concomitant increase in ramp voltage amplitude to maintain constant modulator gain. The input voltage feedforward gain, kFF, is 15, equivalent to the input voltage divided by the ramp amplitude, VIN/VRAMP. See Section 9.1.3 for more detail.