Max662 in programmer?

[kentken]

Has anyone used the Max662 in there programmer for MCLR?
I am looking for a laptop programer for latter upgrades.

Kent

 

[Nigel Goodwin]

Has anyone used the Max662 in there programmer for MCLR?
I am looking for a laptop programer for latter upgrades.

Kent

Assuming the MAX662 is used to generate the 13V MCLR/Vpp supply, I've seen a couple of programmers that use it.

 

[kentken]

It puts out 12v 30ma.
Is there anything else that could be a issue?
What ma is required for programming?

I have found that 12v is enof for my processors.

Why is the common 13v and not 12v?
Am I missing something?


Thanks
Kent

 

[Nigel Goodwin]

It puts out 12v 30ma.
Is there anything else that could be a issue?
What ma is required for programming?

It varies from processor to processor, the new ones take hardly anything, but even the old ones don't take very much - you could always try measuring it, I can't say I've ever bothered!. The biggest current is likely to be the Vpp LED.

I have found that 12v is enof for my processors.

Why is the common 13v and not 12v?
Am I missing something?

The spec from MicroChip is for 12V, but most programmers use 13V as it's usually more reliable - if your 12V rail is only 11.9V it might not work, but if your 13V rail is only 12.9V you've got plenty in hand.

 

[kentken]

I will see if they make one that puts out 13v. I think that I saw on that was variable up to 40v :?:

I gess I will try it, if it don't work, it don't work.
But if it does, it will be much easer then trying to use a external supply.

If you can think of anything else, please let me know.

Thanks
Kent

 

[Exo]

Mine just runs on 2 9V batteries in series, giving 18Volt, wich goes trough an 7815, so i have a VPP of 15V... never had any problems with it and it's much simpler then using special chips to produce 13V

 

[kentken]

I thought of using that approch.
But I heard they have problems if the batteries aren't a full charge all the time.
So I wanted something portable, simple and compact.

I might re-think that design

Thanks
Kent