TPS53676 supports adaptive voltage positioning (AVP) through the VOUT_DROOP PMBus command. This feature is also referred to as the DC load line (DCLL) for the control loop. Use a non-zero DC load line to reduce output voltage set-point as a function of the load current, with a controlled slope. This feature is optional. Set the DC load line to 0.0 mΩ in applications which do not use a load line.

The DC load line provides two main benefits:

• Reducing the output voltage set-point, reduces the power consumption of the system, when the load current is high.
• Adaptive voltage positioning increases the allowable undershoot and overshoot during load transient events. Figure 7-17 and Figure 7-18 compare example output voltage specifications for systems with zero load line and non-zero load line. The nominal setting for the output voltage is chosen to be higher, to allow the entire transient window as margin for transient overshoot and undershoot.

Figure 7-17 Load transient specification (zero load line)

Figure 7-18 Load transient specification (non-zero load line)