SLYY205A March   2021  – October 2022 TPS562211 , TPS562212 , TPS562231 , TPS563211 , TPS563212 , TPS563231 , TPS56339

 

  1.   At a glance
  2.   Authors
  3.   What is AECM control?
  4.   PCM
  5.   D-CAP2 control scheme
  6.   AECM control benefits
  7.   How AECM control works
  8.   PWM operation mode
  9.   PFM operation mode
  10.   Smart loop-bandwidth control
  11.   Conclusion
  12.   References
  13.   Additional Resources

How AECM control works

The PWM mode control scheme is similar to PCM control. As shown in Figure 8 on the following page, the internal clock initials one on-pulse; the high-side FET then turns on, with current increasing in the inductor. When the emulated ramp voltage, feedback voltage and slope compensation voltage reach the integrated reference voltage, the high-side FET turns off and the low-side FET turns on until the next clock cycle. Therefore, in PWM mode, the switching frequency is truly fixed.

Figure 8 AECM control scheme waveform: PWM operation mode (a); PFM operation mode (b).

Figure 9 shows the load-transient behavior of the AECM device. The duty cycle increases or decreases with a decrease or increase of VOUT.