AN2566 Datasheet, PDF (18/29 Pages) STMicroelectronics – PM6680 evaluation kit dual step-down controller

Test setup and performance summary
Figure 8. Section 1 soft-start waveforms
AN2566
OUT1
I_L
EN1
Figure 9. Section 2 soft-start waveforms
OUT2
I_L
EN2
Driving the SHDN pin below the SHDN device “off” threshold will cause the device to enter
shutdown mode. In this case the switching outputs are connected to ground through an
internal 12 Ω power MOSFET and are discharged softly, (discharge mode). When the output
voltages reach 0.3 V, the low side MOSFETs are turned on, quickly discharging them to
ground.
18/29