Freescale USB Development Board USB-KW40Z User’s Guide, Rev. 0, 10/2015

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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).