Help with Nano CPX 3 in 1 board components

[Silverexpress01]

Hello everyone,

Can you guys/gals help me identify the fets on the board. Attached is a pic of one side. I'll post the other later on....

Updates:
12/26/14 Pictures updated with below info
12/26/14 Added Youtube video of Mosfet.

Video's:

Transistor / MOSFET tutorial (4 min 50 sec)

- Mosfet info

Threads (some I use for reference and may not directly pertain to the Nano CPX):
Wrong type of Regulator: http://tinyurl.com/my2guyu
MCPX Receiver Info: https://www.helifreak.com/showthread.php?t=427772
Board troubleshooting info: http://tinyurl.com/mzos6v5

[NCcraig]

I see no attachment.

[Silverexpress01]

Sorry about that. Attached now in first post.

[megasmicros]

#1 tail fet, I use a 7A pfet. #2 main motor fet and I actually use the same as tail fet. #3 3.0 v regulator #4 2.7V regulator

[megasmicros]

#1 #2 10k resistors

[Silverexpress01]

Thanks Megasmicros! I'll update the pics when I get the chance.

[profilefan]

Originally Posted by megasmicros

#1 tail fet, I use a 7A pfet. #2 main motor fet and I actually use the same as tail fet. #3 3.0 v regulator #4 2.7V regulator

Sorry to hijack thread, but on the stock tail fet do you think it can handle a 120sr tail motor or is it necessary to change to 7A pfet?

[megasmicros]

A stock fet can handle the 120sr tail motor but the 7A replacement will do a lot better.

[profilefan]

Originally Posted by megasmicros

A stock fet can handle the 120sr tail motor but the 7A replacement will do a lot better.

Okay great, thanks for the quick reply!

[thaddeusthompsonsr]

Do you have the part numbers for the 7A 's?

[NCcraig]

Originally Posted by thaddeusthompsonsr

Do you have the part numbers for the 7A 's?

Digikey # SI2333CDS-T1-E3CT-ND

[Silverexpress01]

Anyone know what the part numbers are for the 3.0v and 2.7v voltage regulators? Or can anyone verify the part numbers below?

Both are from MicroChip

2.7v LDO Voltage Regulator part number MCP1700T-2702E/TT
Voltage output: 2.7 volts
Current output: 250 ma
Voltage Dropout: 0.178V @ 250mA
Voltage Input: Up to 6v
Case: SOT23-3 (3 legs)

3.0v LDO Voltage Regulator part number MCP1700T-3002E/TT
Voltage output: 3 volts
Current output: 250 ma
Voltage Dropout: 0.178V @ 250mA
Voltage Input: Up to 6v
Case: SOT23-3 (3 legs)

attached is the spec data....

Mouser did not carry the 2.7v version. Digi-key only sold reels of 3000 :-( . For the 3.0v, Megasmicro is out of stock, but am not sure of the manufacturer or part number he is selling.

[Silverexpress01]

So, basically the Blade BL kit blew my main motor mosfet, and this is what led me to look into all this info. This thread is basically a repository of the info I've come upon which dots this vast e-land we call the Internet. Bits and pieces surface based on the wording of my searches.

Enjoy....I'll keep adding as I find more info....

[Silverexpress01]

From Coredump:
http://tinyurl.com/panv7mg Reflow and Conformol Coating removal
http://tinyurl.com/n44zu6h Tip on re-soldering the tiny female servo recepticles on the board
http://tinyurl.com/oezkeft 2.7v Receiver Voltage Regulator info
http://tinyurl.com/o2yq98w Pic of conformal crack on receiver chip
http://tinyurl.com/ps7h93d Transplant RX surgery

From MegasMicros:
http://megasmicros.blogspot.com/ Blog with real good info on FETs, LVC (Low voltage cutoff), and OVC (over current protection)
http://tinyurl.com/ozyf4v9 same stuff but posted on helifreak with replies.

[Silverexpress01]

Servo Info

From MegasMicros:
http://tinyurl.com/lfjqozb

[Silverexpress01]

Invensense Gyro info

http://www.geeetech.com/wiki/index.p...scope_Breakout

[Silverexpress01]

Although the info is for the Mcpx, the same applies to the Ncpx.

http://tinyurl.com/qeanomf Blown tail motor fet, and transistors used between FETS and CPU
http://tinyurl.com/k3o7xqm Description of Diode used on the main and tail motors. Found near the motor connectors (MCU side). Schottky mod.
http://tinyurl.com/mdlzcfy More on the Diodes
http://tinyurl.com/qeeqmww More on the Diodes
http://tinyurl.com/nu2r9bx Mention of Diodes original part number

Real good troubleshooting guide for the tail motor. Also provides a good line on the MCU signal-to-motor circuit.
http://tinyurl.com/otudwy5

In looking closer at the motor drive circuit, I became curious as to why a Transistor was used to trigger the gate of the Mosfet. Here is a real good write up on why.....

http://electronics-diy.com/electroni...ic.php?id=1012

This is very similar to the circuit used in the Ncpx, msrx, mcpx...etc... Note the diode (flyback) and the use of pullup 10K resistors.

Thus the transistor itself can also be damaged by high current. As noted in the video above, the Mosfet is like a valve that is electronically turned off and on. The transistor is what does this and if it gets damage than that off/on becomes erratic.

----------------------
The following thread mentions the big yellowish tan colored tantalum capacitor located above the voltage regulators. This item can be knocked off in a crash or blown if you plug the battery in incorrectly.

http://tinyurl.com/kmm2s44