Freescale USB Development Board USB-KW40Z User’s Guide, Rev. 0, 10/2015
12
Freescale Semiconductor, Inc.
USB-KW40Z development board
Figure 8. USB-KW40Z board’s optional 32.768 kHz oscillator circuit
4.2.3
Power management
There is one way to power on the USB-KW40Z board, a J5 type-A connector to supply 5 V(V_USB)
directly to the secondary MCU, that includes an internal regulator, 3.3 V output to enable theMKW40Z160
device. The USB-KW40Z power management circuit is shown in
Figure 9
.
Figure 9. USB-KW40Z power management circuit
Additionally, a green LED marked as D1 is available as a power indicator. For current measurements, users
can isolate the MKW40Z160
device, through SH13 cut-trace, this will disable the VCC path (including
LED).
