Figure 3. MKW DC-DC in Buck mode (auto start)
WARNING
This configuration is not recommended for Lithium-ion battery designs as over-discharging this type of battery may lead to
permanent damage, reducing its lifetime or causing degradation effects on performance.
3.3 Boost Mode
In Boost mode, the DC-DC converter accepts input voltage in the range of 0.9 V to 1.795 V. To guarantee startup, the DC-DC
requires a minimum of 1.1 V. The typical conversion efficiency is 90%.
In this mode, the DC-DC converter increases the input voltage, VDCDC_IN, to the below default startup values, and then by
software, those values may be changed:
VDD_1P8 = 1.8 V and VDD_1P5 = 1.8 V
Below is the recommended circuit for the DC-DC converter in Boost mode.
NXP Semiconductors
DC-DC Power modes
MKW4xZ/3xZ/3xA/2xZ DC-DC Power Management, Rev. 3, 04 June 2021
Application Note
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