dead vnd5n07

Testing and development of Megasquirt 3

Moderators: jsmcortina, muythaibxr

robb
MS/Extra Newbie
Posts: 3
Joined: Fri Sep 14, 2012 4:50 pm

Re: dead vnd5n07

Post by robb »

SymTech Laboratories wrote:We stock VND5N07's and are equipped to do SMT rework. Send us an email at sales@symtechlabs.com if you're interested in having us repair your board.
Thankyou for your reply and offer but it is a bit impractical as I am in Australia and the postage would be crazy.
robb
MS/Extra Newbie
Posts: 3
Joined: Fri Sep 14, 2012 4:50 pm

Re: dead vnd5n07

Post by robb »

I took the brave pills and desoldered the FET using a conventional iron. lifted the legs first before prising the body while heating the solder. piece of cake in tha end.
juansh2385
Master MS/Extra'er
Posts: 612
Joined: Fri Feb 25, 2011 4:28 pm

Re: dead vnd5n07

Post by juansh2385 »

So this happen again... James you mention that this is being analyse carefully have you or anybody found a reason why they would fail? In my case in happend with Siemens denka 630cc injectors on a aeb 1.8T that was running flawlessly for a year on ms3/mx3 combo.
jsmcortina
Site Admin
Posts: 39586
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: dead vnd5n07

Post by jsmcortina »

Nothing was found. The circuit matches up with datasheet requirements and endurance testing yielded no failures.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
Matt Cramer
Super MS/Extra'er
Posts: 17499
Joined: Thu Apr 16, 2009 8:08 pm

Re: dead vnd5n07

Post by Matt Cramer »

To add what James noted, our best guess has been that there was a bad batch that was prone to defects. Lately, reports of dead VND5N07s has been way down, even as sales of items with them has been up, which would support that theory.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
juansh2385
Master MS/Extra'er
Posts: 612
Joined: Fri Feb 25, 2011 4:28 pm

Re: dead vnd5n07

Post by juansh2385 »

ok Thanks guys. Matt do you think tha DIYAUTOTUNE will sell these eventually? y just changed the ones that failed with the spares i wasn't using from mx3 expansion? I found them at mouser but you guys ship faster to my location.

Juan
SymTech Laboratories
Super MS/Extra'er
Posts: 2188
Joined: Sun Aug 31, 2008 4:02 pm
Location: South Florida, USA
Contact:

Re: dead vnd5n07

Post by SymTech Laboratories »

juansh2385 wrote:y just changed the ones that failed with the spares i wasn't using from mx3 expansion? I found them at mouser but you guys ship faster to my location.
We have these in stock and ready to ship. Feel free to email us at sales@symtechlabs.com if you need them quickly.
SymTech Laboratories, LLC ----- MSQ File Repository: megasquirt.symtechlabs.com
Image
hardline
Master MS/Extra'er
Posts: 503
Joined: Mon Sep 08, 2008 8:37 pm
Location: Peoria, IL

Re: dead vnd5n07

Post by hardline »

I had 2 of these die at the same time in September on a JBPerf 4 channel injector/coil driver board. Coasted up to a stop, and the car stumbled. It then started sounding like a Boxer 4, and had no power whatsoever. I replaced all 4 with IPD600N25N3 mosfets I sourced from Mouser. After upgrading to MS3, I decided to torture test one of them, which I was able to drive a Low-Z injector off of an RX7 I found torn apart in my local pick-n-pull. The device is rated up to 25 A continuous and has a Source to Drain max voltage of 250V. I am unsure if that means it clamps at 250V, but the data sheet indicates it is avalanche rated. The device was a drop-in replacement on the JBPerf board, and I have 4 left over incase the ones on my MS3X goes belly-up. I am attaching the datasheet so if anyone is interested, they don't have to search for it. IIRC the mosfets were less than $1.50 USD each.
2000 ZX2 : Sequential COP, MS3 + MS3X + TinyIOx, PWM Returnless Fuel, Flex Fuel, Variable Geometry Intake Manifold, Garrett GTX2863R .82AR housing @ 15 psi
jsmcortina
Site Admin
Posts: 39586
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: dead vnd5n07

Post by jsmcortina »

Unless I'm missing something, that device isn't avalanche rated as the VND5N07 device is which will give different injector deadtimes. Do not use in a mix with the VNDs.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
dontz125
Super MS/Extra'er
Posts: 4200
Joined: Mon May 11, 2009 7:14 pm
Location: York, ON
Contact:

Re: dead vnd5n07

Post by dontz125 »

2 of his drivers failed, but he replaced all 4.
QuadraMAP Sensor Module -- PWM-to-Stepper Controller -- Dual Coil Driver
Coming soon: OctoMAP Sensor Module
TTR Ignition Systems
racingmini_mtl
Super MS/Extra'er
Posts: 9128
Joined: Sun May 02, 2004 6:51 am
Location: Quebec, Canada
Contact:

Re: dead vnd5n07

Post by racingmini_mtl »

The breakdown voltage on these is 250V compared to 70V on the VND5N07. In addition to the different deadtimes James mentions, that is going to put a much higher voltage on the injectors which may cause problems so I would seriously hesitate to use them. You can find other similar unprotected FETs that have a 60-80V breakdown voltage which would be much more appropriate for this.

Jean
jbperf.com Main site . . . . . . . . . . . . . . . . . . . . . . jbperf.com Forum
Image
dontz125
Super MS/Extra'er
Posts: 4200
Joined: Mon May 11, 2009 7:14 pm
Location: York, ON
Contact:

Re: dead vnd5n07

Post by dontz125 »

I've done a little reading, but would appreciate a bit of clarification - "breakdown voltage" is the voltage at which the (off-state) Mosfet acts similarly to a Zener, correct?
QuadraMAP Sensor Module -- PWM-to-Stepper Controller -- Dual Coil Driver
Coming soon: OctoMAP Sensor Module
TTR Ignition Systems
hardline
Master MS/Extra'er
Posts: 503
Joined: Mon Sep 08, 2008 8:37 pm
Location: Peoria, IL

Re: dead vnd5n07

Post by hardline »

Yes, Breakdown is when the MOSFet begins to behave like a Zener. So earlier in the thread it was mentioned that the injector may close quicker if it had a higher voltage clamp. 250 Volts, as long as it is in the milliampere range, should be safe for the injector and I had been running those MOSFets for 6 months with no issues. I did notice that when I went to MS3 + MS3X, my Injector opening values had to be modified, and my VE table was a hair rich, especially in the lower pulsewidth region of the table.
2000 ZX2 : Sequential COP, MS3 + MS3X + TinyIOx, PWM Returnless Fuel, Flex Fuel, Variable Geometry Intake Manifold, Garrett GTX2863R .82AR housing @ 15 psi
racingmini_mtl
Super MS/Extra'er
Posts: 9128
Joined: Sun May 02, 2004 6:51 am
Location: Quebec, Canada
Contact:

Re: dead vnd5n07

Post by racingmini_mtl »

Voltage may have an impact regardless of current depending on the coil winding inside the injector and how it is isolated. You could go through the isolation and destroy the injector. I very much doubt that regular injectors are rated for 250V.

Jean
jbperf.com Main site . . . . . . . . . . . . . . . . . . . . . . jbperf.com Forum
Image
hardline
Master MS/Extra'er
Posts: 503
Joined: Mon Sep 08, 2008 8:37 pm
Location: Peoria, IL

Re: dead vnd5n07

Post by hardline »

That is also running on the assumption that the injecor will develop 250v of flyback voltage. I would suspect that a low-z injector would, but I doubt that a high-z injector would. The Low-z injector wiring has to have better insulation on the windings as they draw much more current than the high-z ones do.
2000 ZX2 : Sequential COP, MS3 + MS3X + TinyIOx, PWM Returnless Fuel, Flex Fuel, Variable Geometry Intake Manifold, Garrett GTX2863R .82AR housing @ 15 psi
Post Reply