WEBENCH Power Designer also provides optimization and evaluation of a system in other ways. For example, with the launch of the LM315x SIMPLE SWITCHER controllers, WEBENCH Power Designer now includes more ways to optimize MOSFETs for controller designs. This is especially beneficial since MOSFET selection for controllers can be complex and timely. This will be discussed later in the presentation. The ramp signal used in the pulse width modulator for current mode control is typically derived directly from the buck switch current. This switch current corresponds to the positive slope portion of the output inductor current. Using this signal for the PWM ramp simplifies the control loop transfer function to a single pole response and provides inherent input voltage feed-forward compensation.