Neo-6M GPS Troubleshooting

[Michael3660]

Hi all,

I purchased a GY-GPS6MV2 recently and have had difficulty powering the module.

My first observation was that the onboard regulator was getting quite hot when applying power. This was the case when trying a range of supplies (3.3v @ 50mA/1A, 5v@700mA/1A). Using a DMM inline to measure the current, it appeared that the circuit was trying to draw as much current as possible from the supplies. The supply voltage is being seen at the Vcc/GND pins, however at the regulator input there is a voltage drop occurring.

Next, I tested the circuit for continuity. There is connectivity between the regulator output and GND, and therefore; across the output capacitor and GPS Vcc/GND pins also. Something might be shorting.

Is it possible that the device may be faulty?

[Graham]

Hi Michael,

UBlox are reliable devices, though exposing it to 5V will break it almost straight away. It’s perhaps more likely that the onboard regulator has a short circuit arising from excessive heat, as happens when there’s a path of burnt carbon somewhere internally.

When/if you test with a second, only use 3.3V. Especially for the RX pin, it is not 5V tolerant. Here’s what you would use in between for logic level shifting:

Logic Level Converter Bi-Directional

[Michael3660]

Hi Graham,

To clarify, the Rx/Tx pins were not connected during this testing. I am just attempting to power the GPS module and verify that it can acquire a signal (Which would be indicated by the LED).

I understand the onboard regulator is based on a MIC5205, which has an operating range of +2.5-16V (Although, considering power dissipation best to be within 6V). So supplying 5V shouldn’t be a problem. In fact, 3.3V might not be enough to power the circuit when you factor in the dropout voltage of the regulator.

It seems to me that there is a fault somewhere in the circuit, but I cannot pin down exactly where at the moment.

Given this, is there anything else you can suggest?

[Stephen]

Michael,

Would you be able to provide a picture/sketch/diagram of how you were wiring everything up for testing?

Thanks!

[Michael3660]

Hi Stephen,
Refer picture above.
In terms of voltages around the board, I am measuring:
Vcc/gnd (Supply) = 5V
Vin (Regulator) = 3.5V
Vout (Regulator) = 2.5V
Consequently the voltage to the GPS is too low and won’t work.

[John74406]

Hi Michael.

Did you solve this problem?

I too have a GPS board with a Neo-6M that runs hot and never achieves a fix (although it does get many sat signals at good strength).

One tiny component gets too hot to touch.

I use 3.3V from the Arduino board and don’t connect the RX pin, just the TX.

[Stephen]

Hi John,

Are you outside when powering up your device? It may be causing problems that it is not wired up properly. Can you provide a diagram/schematic of your wiring?

[John74406]

Hi Stephen.

Here are images of the module from the seller:

Neo-6M GPS breakout board

I connect it to the laptop via the USB connector. After a minute the unit is overheating. The receiver itself is hot to the touch, the antenna is hotter but still touchable. The tiny component labelled “R5” (resistor? regulator?) is so hot it would burn skin. Powering it with 3.3V gives the same result.

No other connections to the board. No sense in worrying about getting a fix if it overheating to this extent.

I have an identical unit and a similar unit that do not get warm at all. Both of these readily achieve a fix, but the overheating one never has. I don’t expect to ever get it working. Something is very wrong with it.

I have no way of knowing if the fault was present when I received it or a result of something I did. Next one I purchase, first task will be to test it for overheating.

[Stephen]

Hi John,

That sounds like a fault on the board, as there is no reason anything should be getting super hot on a GPS module.