SLVSE72B September 2017 – June 2018 TPS565208
PRODUCTION DATA.
The main control loop of the TPS565208 is adaptive on-time pulse width modulation (PWM) controller that supports a proprietary D-CAP2™ mode control. The D-CAP2™ mode control combines adaptive on-time control with an internal compensation circuit for pseudo-fixed frequency and low external component count configuration with low-ESR ceramic output capacitors. It is stable even with virtually no ripple at the output.
At the beginning of each cycle, the high-side MOSFET is turned on. This MOSFET is turned off after internal one-shot timer expires. This one shot duration is set inversely proportional to the converter input voltage, VIN, and proportional to the output voltage VO, to maintain a pseudo-fixed frequency over the input voltage range, hence it is called adaptive on-time control. The one-shot timer is reset and the high-side MOSFET is turned on again when the feedback voltage falls below the reference voltage. An ripple is added to reference voltage to simulate output ripple, eliminating the need for ESR induced output ripple from D-CAP2TM mode control.