SLUSDB2A August 2018 – December 2021 UCC28951
The error amplifier has two uncommitted inputs, EA+ and EA–, with a 3-MHz unity gain bandwidth, which allows flexibility in closing the feedback loop. The EA+ is a noninverting input, the EA– is an inverting input and the COMP is the output of the error amplifier. The input voltage common-mode range, where the parameters of the error amplifier are ensured, is from 0.5 V to 3.6 V. The output of the error amplifier is connected internally to the noninverting input of the PWM comparator. The range of the error amplifier output of 0.25 V to 4.25 V far exceeds the PWM comparator input ramp-signal range, which is from 0.8 V to 2.8 V. The soft-start signal serves as an additional noninverting input of the error amplifier. The lower of the two noninverting inputs of the error amplifier is the dominant input and sets the duty cycle where the output signal of the error amplifier is compared with the internal ramp at the inputs of the PWM comparator.