questions about micro boost drive

[ndrew2505]

i got my 2 micro boost drives in today and was proceeding to switch out the flex v4 i have driving my 445 diode but i have ran into a problem..

after setting the correct jumpers for the range i want and attaching the dummy load(set for BR diodes) i proceeded to attach a power supply. the problem is that i want to drive it ~900ma-1A... everything seems to go fine until i crank up the current.. the driver gets so hot im afraid it might kill the driver. its currently "set" to ~930ma but after about half a second the current starts dropping as the driver gets hotter. everything has been hooked up correctly as far as i know of and no other connections have been bridged. anyone have an idea of what may be going on?

the specific part getting hot is the 6pin chip on the opposite side of the potentiometer. this is also affecting both drivers..

 

[daguin]

i got my 2 micro boost drives in today and was proceeding to switch out the flex v4 i have driving my 445 diode but i have ran into a problem..

after setting the correct jumpers for the range i want and attaching the dummy load(set for BR diodes) i proceeded to attach a power supply. the problem is that i want to drive it ~900ma-1A... everything seems to go fine until i crank up the current.. the driver gets so hot im afraid it might kill the driver. its currently "set" to ~930ma but after about half a second the current starts dropping as the driver gets hotter. everything has been hooked up correctly as far as i know of and no other connections have been bridged. anyone have an idea of what may be going on?

the specific part getting hot is the 6pin chip on the opposite side of the potentiometer. this is also affecting both drivers..

I have run these as high as 800mA without problems. I believe that other s have gone higher. This is happening with the dummy load? Can you describe all of your solder connections (or scan an image for us)

Peace,
dave

 

[jayrob]

One thing to watch out for with this driver, is that you cannot connect your supply negative the the driver output negative like you could with a FlexDrive.

Supply negative must only be connected to driver input negative...

Just in case that was the problem...

 

[ndrew2505]

the dummy load gets hot too but the driver is what concerns me.. the solder connections are all clean and the jumpers are set for the highest range. ive read the sheet drlava included with the driver and cant figure out what may be wrong.. all my connections are clean and in the proper places. atm all i have is my crappy camera on my dare...

ive tried powering with a modified computer psu on the 3v and 5v rail as well as trying a 16340 and a 18650..

 

[Pontiacg5]

That is odd, I've had 2 of them up to around 800mA and they do get warm, but don't loose any power.

I personally love the little buggers, except for the issue Jayrob pointed out. It makes for extra steps when building pens!

 

[ndrew2505]

That is odd, I've had 2 of them up to around 800mA and they do get warm, but don't loose any power.

I personally love the little buggers, except for the issue Jayrob pointed out. It makes for extra steps when building pens!

you can use a small piece of spring steel(like from the lens spring from an aixiz module) and strip the coating off to use from the - on the driver to connect with the case. ive done it a couple of times.

 

[jayrob]

I've set at least 20 of them so far, and they have all been perfect...

It should not be getting hot like that. You'll have to see if drlava may have an answer...

 

[TheGr8Revealing]

Are you using 4 or 6 N4001's in your dummy load? Also, I've only been able to get my v5 up to about 830mA before it just wont push anymore. Any higher and the driver gets extremely warm just as in your case.

 

[Pontiacg5]

you can use a small piece of spring steel(like from the lens spring from an aixiz module) and strip the coating off to use from the - on the driver to connect with the case. ive done it a couple of times.

I've just been wiring the case pin to the driver input, works like a charm

 

[ndrew2505]

Are you using 4 or 6 N4001's in your dummy load? Also, I've only been able to get my v5 up to about 830mA before it just wont push anymore. Any higher and the driver gets extremely warm just as in your case.

im using a rkcstr dummy load set to BR. im trying to set a micro boost not a v5 flex.. :tinfoil:

 

[jayrob]

you can use a small piece of spring steel(like from the lens spring from an aixiz module) and strip the coating off to use from the - on the driver to connect with the case. ive done it a couple of times.

Another way to do it, is to use the diode case pin... (case neutral diode only)

If the module is in contact with the case, then the diode case pin will be negative. (in a case negative build)

So all you have to do, is connect a third wire. (isolated) One that goes from the diode case pin, to the driver negative input!

 

[Morgan]

I may be misunderstanding but doesn't the manual say you cannot use the case as a ground with a MicroBoost? This may not be your problem but something to bare in mind.

M

 

[ndrew2505]

I may be misunderstanding but doesn't the manual say you cannot use the case as a ground with a MicroBoost? This may not be your problem but something to bare in mind.

M

see pic in post above..

i just tried on different current settings(~840ma) and it does the same thing.. current automatically starts dropping and chip heats up...

 

[daguin]

We're missing something . . . . .

How much voltage are you feeding the driver?

Peace,
dave

 

[ndrew2505]

3v, 5v, and 3.7v

3v and 5v rail from modified cpu psu and 16340 and 18650 batts

 

[daguin]

3v, 5v, and 3.7v

3v and 5v rail from modified cpu psu and 16340 and 18650 batts

Just trying to break something loose (mentally). I don't see the problem. :thinking:


Peace,
dave