N4 expansion boards for BLDC

[afernan]

Very nice work Jussi!. Nothing but an experienced user to design what we really need!
Already bought a couple of them.

Thanks.

[fseider]

Hi,

I have the N4 assembled but no LED lights, neither the LED for power nor the LED for pairing. The M4 is powered correctly.
I have the BT modules completely soldered and not like the picture shows only partially.

Is this OK or is there something wrong?

Regards Frank

[JussiH]

Is the BT_PWR jumper closed:

http://autoquad.org/wp-content/uploads/ ... _BTPWR.jpg

The connections soldered in the photo is the ones used and some corner pins to keep the module in place. Remaining ones are not connected, so it doesnt harm anything to solder them, but its not needed either.

[fseider]

Yes, the jumper is closed

[JussiH]

Check if you have 3.3V on the supply pin to the Bluetooth:

N4_BT_pwr_pins.jpg (80.47 KiB) Viewed 12417 times

Check for short between 3v3 and GND on the module.

IC1 on the top side of the board is the 3.3 LDO regulator. Check to see if it gets 5V and is putting out 3.3V

[kinderkram]

These are the only 4 needed:

[fseider]

Everything seems to be OK, but no LED...

[JussiH]

So, the module is getting 3.3V?

Can you connect the module to a phone or PC?

If so it might just be a problem with the LEDs themselves. You should see pulses of 3.3V on R14 (PWR Led blinks) when the module is powered. Once the module is paired AND connected you should get steady 3.3V on R13. (Pair LED is solid)

Check also for shorts on pin 31 and 32 (The LED pins) on the BT module. Add flux and reflow those 2 pins. Things are tight around there with the UART connector so not the easiest soldering...

[fseider]

No, I can't connect the modul! R14 = 0V and no shorts between Pin 31 and 32...

[fseider]

I have checked all soldering points and all are OK No short circuit or something else. The Voltage is OK. 5v, 3,3V... Only the BT Module won't work.

Any Ideas?

Regards Frank