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I have a portable GPS and want to use an AC adapter. I have a 5.15v 1 A LPS and the GPS is 5v. Any issue with using that?

db5 wrote: ↑Sun Sep 25, 2022 1:26 pm This is one of only 2 forums I trust for accurate information and the bad information on the internet is abundant.

I have a portable GPS and want to use an AC adapter. I have a 5.15v 1 A LPS and the GPS is 5v. Any issue with using that?

I would go for it but then I won't be the one to lose a GPS if wrong.

What is the Model # of the GPS? Documentation should reveal the secret.

The standard for ordinary US 120v service is +-5%, which is about 114v to 126v and works out to anywhere between 4.76v and 5.25v at a 5v adapter; so I'd be surprised if the GPS couldn't tolerate a 3% hike from 5v to 5.15v. But as Dusty says, it's not my GPS ...

You might want to first determine what kind of battery is in the GPS. Some use lithium batteries and others could use lead acid or other types of batteries. Lithium batteries can be touchy about the type of charger they want. (Yes, lithium ion batteries like to blow up if charged improperly.)

db5 wrote: ↑Sun Sep 25, 2022 1:26 pm This is one of only 2 forums I trust for accurate information and the bad information on the internet is abundant.

I have a portable GPS and want to use an AC adapter. I have a 5.15v 1 A LPS and the GPS is 5v. Any issue with using that?

Having designed these (GPS and etc.) for many years, my advice would be "it depends". The core issue is what semiconductor technology was used for the IC's inside of the devices and what, if any, input protection they have to protect them. When I started out in the industry, many of our IC applications supported a +/-5% tolerance on the input supply, but as the technology advanced (smaller semiconductor nodes) this quickly dropped to +/-3% and some are even lower than this (smaller geometry-more advanced semiconductor nodes are less resilient to supply variations). Personally I would not put more than +/-3% of the nominal rated supply because of this. IF it is a 5.0V nominal supply then that would be 4.85V to 5.15V, i.e. do NOT go above 5.15V (including ripple/noise). Semiconductor devices can tolerate a certain level of EOS (electrical over stress) and this typically only degrades the transistors, resistors, capacitors a bit...often not affecting performance though it may shorten the lifetime of the device. However the bigger concern I would have is that dependent on the technology of the semiconductor process you might cause one of the ESD devices to clamp on the higher supply resulting in excess current draw and possibly breakdown leading to a non-functional device. So be careful about going "too high" above the rated nominal supply on any modern electronics especially if it uses more modern technology nodes in it. IF the engineering team that designed the device was particularly savvy in PMIC (power management integrated circuits) and/or if the application calls for a very robust IC for these kinds of voltage swings, then the input will be a lot more tolerant, but this is seldom the case IMHO. You could always reach out to the manufacturers and ask them...the customers I have worked with (GPS field) typically have pretty good sales and application support teams who should be able to find out the answer to give you peace of mind.

As always, this is the forum to get good information and advice when all others fail. Thanks. It's LION so I'll not use this charger.

Sounds like you might blow up the battery, but if you're lucky it won't ruin the whole device. So as Clint Eastwood would say- "You've got to ask yourself one question: 'Do I feel lucky?'

I wouldn't do it. The proper charger can't cost all that much.

"The proper charger can't cost all that much." Garmin wants $30 (plus tax and shipping). About half that for other stuff from CCCP on Amazon.

db5 wrote: ↑Thu Sep 29, 2022 1:22 pm "The proper charger can't cost all that much." Garmin wants $30 (plus tax and shipping). About half that for other stuff from CCCP on Amazon.

Do you know the specs of the Garmin charger? IF so, you could try to match a similar off-brand one to it. However, be careful of the "cheap" chargers and other electronics from China on Amazon. I am amazed at how many people buy an expensive smartphone, such as an iPhone or Samsung, and then buy a secondary charger off of Amazon. IF you are only paying $5-10 for a wall charger...one that is a switching charger...don't be too surprised when there is equipment failure down the road. Personally I would never buy a $1k smartphone and hook up a cheap $10 charger to it because I know better. Not saying you can't get a good off-brand replacement, but just look for a decent brand, e.g. I like Belkin and Anker. Yes, almost all of these products are manufactured in China, but there is a difference in quality as some Chinese products are fly-by-night operations and have no quality control and poor designs to begin with.

db5 wrote: ↑Thu Sep 29, 2022 1:22 pm "...from CCCP on Amazon."

I thought the Soviet Union (Союз Советских Социалистических Республик) dissolved in 1991.... (ducks)