Figure 19. Turn on time
The green curve in Fig. 19 shows when code starts executing. Note that the CPU starts before the DC-DC output voltage is
completely stable (DCDC_STS_DC_OK = 1). It is important that application maintains a constant load and does not make changes
that can affect the loading until DC-DC is stable (yellow curve). Just after the voltage stabilization occurs, the application may add
extra loads, such as turning on internal modules or draining high current on GPIOs.
6.3.2 Settle Time
Below there are two examples showing the VDD_1P8 output voltage change. For both cases, the VDCDC_IN is 3.6 V and there
were no external loads.
NXP Semiconductors
Current estimation and efficiency report
MKW4xZ/3xZ/3xA/2xZ DC-DC Power Management, Rev. 3, 04 June 2021
Application Note
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