FRDM-KL25Z Power Supply Options

[serhatitu]

Hello ,

i want to use 9V power supply instead of USB from J9->pin16 .

How can i do that , is it possible?

i have tried it without success

Thanks for your help

[rahulyamasani]

Hello Erich,

I too have the same problem. I tried to give external power supply through power bank (5.1V, 2Amp)to my KL25Z through USB. When in connect the power supply, the LED (D4) that indicates the status of board is not getting on. Then gave external power supply to V IN and Gnd as suggested by you. Surprisingly, my board got heated up and I immediately removed the power supply from V IN and Gnd.

Also I couldn't find any diode D1 near my USB KL25Z. The layout of my board is different from what you have shown on https://mcuoneclipse.com/2013/05/12/fix-for-3-3v-voltage-drop-on-frdm-kl25z-board/.​ For Reference I am attaching a picture of my Freescale board.

Any Suggestions of how I could Solve this problem.

Thanks.

[ZhangJennie]

hello,

this is a thread of 3 years ago, now for better support, can you please create a new thread for your question?

thanks!
Jennie Zhang

[BlackNight]

Hello,

yes, I did this (using LiPo batteries). Keep in mind that you need a 5V regulator/booster/up/down converter.

See http://mcuoneclipse.com/2013/06/21/5v-generation-from-v_in-on-the-freedom-board-reve/

For the RevD board see an example here:

Zumo Line Following with FRDM-KL25Z | MCU on Eclipse

I hope this helps.

[serhatitu]

Hello Erich,

Thanks for your fast reply . Firstly ,my board is FRDM-KL25Z not FRDM-KL25Z RevE. i have attached page about power supply options.

Actually i want to use external power supply instead of  USB . Document says you can give 4.3-9V from J9->pin16 to the FRDM-KL25Z ,  i have tried to give 5V , 7V and 9V to the FRDM-KL25Z none of them activate board.

How can i supply board from external Power supply?

[BlackNight · Accepted solution]

I connect GND and 7.4V from a LIPO to GND and V_IN.

If you do not need 5V, that's it.

But I have modified my RevD boards (see Fix for 3.3V Voltage Drop on FRDM-KL25Z Board | MCU on Eclipse) to avoid the voltage drop over the diode.

Erich

[serhatitu]

thanks Erich