Did you look at these https://www.st.com/en/reset-and-supervi ... m1816.htmlexxos wrote: ↑Mon Nov 12, 2018 12:27 am http://www.ti.com/product/TPS3808/technicaldocuments
Looks good.. But output drive seems a bit wimpy
I guess a small MOSFET could be used to beaf it up.. Still smaller than a TTL chip..
RESET circuit tweaks
Re: RESET circuit tweaks
Re: RESET circuit tweaks
That looks cool as well. I only had a quick look at TI so far..Icky wrote: ↑Mon Nov 12, 2018 7:03 am Did you look at these https://www.st.com/en/reset-and-supervi ... m1816.html
I am thinking though that a programmable delay time might be better as I don't actually know what the reset time is of the ST... 0.2s might be fine, though I was thinking of more like 0.5 second.
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
Re: RESET circuit tweaks
https://www.mouser.co.uk/datasheet/2/38 ... 250874.pdf
https://www.mouser.co.uk/ProductDetail/ ... 2bx6HAI%3d
MIC6315 - cheapest one in mouser... 200ms delay, manual reset, 20mA seems about as good as anything gets...
This wouldn't technically need the external buffers, my only slight concern is that there is RESET & HALT which are actually two different signals which need to be driven independently.. This could be done with 2 diodes.. Or I guess use 2 logic level MOSFETs to do the actual switching independently... Or we could just use two of these chips..
Logic level MOSFETs would have been my first choice, but the problem is this is a additional part... If we were going to have additional parts anyway, it would make sense to just use two of these chips then it is only actually one part, and buying more one part generally gets better price breaks.
It would have been nice just to have done this all in one part, but it does do away with the external buffering, so it wouldn't really be any more expensive in using two chips, but the footprint is obviously a lot smaller and of course is just one single part..
I will have a look and see if there is anything else, there are chips which have multiple monitoring inputs, so one of those might be better suited....
EDIT:
I'd say this one is the best candidate to try next...
https://uk.farnell.com/microchip/mic631 ... st=MIC6315
Even though I detest evil bay....
https://www.ebay.co.uk/itm/5pcs-SOT-143 ... :rk:1:pf:0
It would be far quicker to obtain these than wait for them to come from a pcb fab house for a month...
https://www.mouser.co.uk/ProductDetail/ ... 2bx6HAI%3d
MIC6315 - cheapest one in mouser... 200ms delay, manual reset, 20mA seems about as good as anything gets...
This wouldn't technically need the external buffers, my only slight concern is that there is RESET & HALT which are actually two different signals which need to be driven independently.. This could be done with 2 diodes.. Or I guess use 2 logic level MOSFETs to do the actual switching independently... Or we could just use two of these chips..
Logic level MOSFETs would have been my first choice, but the problem is this is a additional part... If we were going to have additional parts anyway, it would make sense to just use two of these chips then it is only actually one part, and buying more one part generally gets better price breaks.
It would have been nice just to have done this all in one part, but it does do away with the external buffering, so it wouldn't really be any more expensive in using two chips, but the footprint is obviously a lot smaller and of course is just one single part..
I will have a look and see if there is anything else, there are chips which have multiple monitoring inputs, so one of those might be better suited....
EDIT:
I'd say this one is the best candidate to try next...
https://uk.farnell.com/microchip/mic631 ... st=MIC6315
Even though I detest evil bay....
https://www.ebay.co.uk/itm/5pcs-SOT-143 ... :rk:1:pf:0
It would be far quicker to obtain these than wait for them to come from a pcb fab house for a month...
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
Re: RESET circuit tweaks
Challenge acceptedexxos wrote: ↑Mon Nov 12, 2018 2:08 pm
EDIT:
I'd say this one is the best candidate to try next...
https://uk.farnell.com/microchip/mic631 ... st=MIC6315
Even though I detest evil bay....
https://www.ebay.co.uk/itm/5pcs-SOT-143 ... :rk:1:pf:0
It would be far quicker to obtain these than wait for them to come from a pcb fab house for a month...
Re: RESET circuit tweaks
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
Re: RESET circuit tweaks
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
Re: RESET circuit tweaks
I rebuilt the original reset circuit as a hack to leave the reset circuit part of the board empty ready for testing the new reset chip.
Thought I would just share the ugliness of my hack that allows me to boot and reset. Made even the more ugly as I had to use lead free solder.
However it works and I can pull the chip out to test.
Thought I would just share the ugliness of my hack that allows me to boot and reset. Made even the more ugly as I had to use lead free solder.
However it works and I can pull the chip out to test.
Re: RESET circuit tweaks
9 out of 10 for ugliness, some of those connections look far too well soldered for a 10.
If it ain't broke, test it to Destruction.
Re: RESET circuit tweaks
Man if that was a Joe Master cap in the center it would look like a blue beatle being eaten by ants!!Icky wrote: ↑Fri Nov 16, 2018 2:49 pm I rebuilt the original reset circuit as a hack to leave the reset circuit part of the board empty ready for testing the new reset chip.
Thought I would just share the ugliness of my hack that allows me to boot and reset. Made even the more ugly as I had to use lead free solder.
However it works and I can pull the chip out to test.
IMG_3288.png