ZHCSJU9E January 2007 – June 2019 TPS40077
PRODUCTION DATA.
Voltage-mode, buck-type converters are typically compensated using Type III networks. Because the TPS40077 uses voltage feed-forward control, the gain of the voltage feed-forward circuit must be included in the PWM gain. The gain of the voltage feed-forward circuit, combined with the PWM circuit and power stage for the TPS40077 is Equation 4.
where
The remainder of the loop compensation is performed as in a normal buck converter. Note that the voltage feed-forward circuitry removes the input voltage term from the expression for PWM gain. PWM gain is strictly a function of the programmed start-up voltage.