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Problem - how to discharge a capacitor ONLY after the voltage has dropped to around 6VDC.

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Indeed, the 5VDC switcher draws the Cin down to around 7VDC at which point it shuts down. It won't start up until Vin is under 4.0VDC. So, really, one just needs to knock off 3VDC off Cin as quickly as reasonable (1 second perhaps?) but not loading down Cin too much during the power up cycle.

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If I wasn't in the midst of moving my business which consists of a shop that is 3,300 sq ft and 1500 sq ft storage into a larger warehouse I'd be all over that.

I'll be taking a fresh look at this in a couple of weeks once I have my bench set up again.

Thanks!

John :-#)#

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(Please post followups or tech inquiries to the USENET newsgroup) 
John's  Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 
          (604)872-5757 (Pinballs, Jukes, Video Games) 
                      www.flippers.com 
        "Old pinballers never die, they just flip out."
Reply to
John Robertson
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1 second is gravy. The only question is, how much is too much load? Actually, if you are driving 5 amps at 5 volts, even with a 15 volt into a buck converter you are talking about well over 1 amp to bring up the PSU into a load. So 40 mA won't be a big issue. That's what the simulation shows at 1 second.

Heck, I don't get why the 220 ohm resistor is a concern. You could always use an LED with a series current limiter and have a pilot light!

--

Rick C
Reply to
rickman
[snip]

Reliability score, -1000. ...Jim Thompson

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| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| STV, Queen Creek, AZ 85142    Skype: skypeanalog |             | 
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  | 
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     Thinking outside the box... producing elegant solutions. 

"It is not in doing what you like, but in liking what you do that 
is the secret of happiness."  -James Barrie
Reply to
Jim Thompson

I appreciate the thought, however, that product is fine if you are designing a game from scratch, but here I am trying to find a simple solution (that requires a minimum of customer work) that doesn't introduce the element of electrical shock risk where people are trying to connect to the AC line.

The replacement part I would like to use requires unsoldering one part that has two solder connections. Hard (but not impossible of course) for the average person to screw up, and possibly risk personal harm.

John

--
(Please post followups or tech inquiries to the USENET newsgroup) 
John's  Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 
          (604)872-5757 (Pinballs, Jukes, Video Games) 
                      www.flippers.com 
        "Old pinballers never die, they just flip out."
Reply to
John Robertson

Too much additional stuff to add a 555 timer.

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup) 
John's  Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 
          (604)872-5757 (Pinballs, Jukes, Video Games) 
                      www.flippers.com 
        "Old pinballers never die, they just flip out."
Reply to
John Robertson

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