Introduction to Digital Power Conversion
XMC4000/1000 Family
Control Loops
Application Guide
80
V1.0, 2015-01
CCU 4 Slope Compensation respective CCU 4 Blanking Control
The CCU 4 Slope Compensation MOSFET is OFF during each PWM pulse; i.e. the capacitor voltage
can ramp up by current from V
DD
via a resistor. This ‘SC-Ramp’ voltage and the Current Measurement
voltage are added via a respective resistor to the ACMP/P input and so invoke Slope Compensation.
Each time the CCU 4 Slope Compensation MOSFET is ON, it discharges the capacitor. The CCU 4
Blanking MOSFET works synchronously, and rejects noise by forcing the ACMP/P input to ground.
CCU 4 as DAC Control
The RC-network at the ACMP/N input holds a fixed reference voltage, at a desired peak detection
level, by low-pass filtering the chopping effect from the MOSFET, controlled by the CCU 4 as DAC.
