I've retired & want to get into electronics as a hobby.

I've wondered about how to power the breadboard. Elsewhere on this forum I asked about connecting wall warts in series or parallel. They don't recommend it. So, I can use batteries or wall warts (but not connected ones!) or adapt a PC power supply. I have a 12 A mophie that I use to recharge my smartphone & iPad. Can I use a mophie or similar power pack to power a breadboard?

According to Wikipedia, the USB standard allows up to 5 amps output.

 

I have a 12 A mophie

What's one of those. I don't recognise it at all but that may be an effect of that large volume of water between us !

 

What's one of those. I don't recognise it at all but that may be an effect of that large volume of water between us !

Greetings from across the pond!

Here's a link to the mophie website:
http://www.mophie.com/shop/universal-batteries

I considered sealed lead-acid batteries but that's an ancient technology & the charger is expensive & the batteries have to be left on trickle charge 24/7.

I've noticed that D cells have a higher current output than AAA cells. So, one option that I have is to get d-cell battery holders & use those as a power source. I considered rechargeable D-size lithium-ion batteries, but they are expensive - like $20 each!

So, that leaves NiMH or alkaline batteries or maybe something akin to the mophie.

 

I've retired & want to get into electronics as a hobby.

I've wondered about how to power the breadboard. Elsewhere on this forum I asked about connecting wall warts in series or parallel. They don't recommend it. So, I can use batteries or wall warts (but not connected ones!) or adapt a PC power supply. I have a 12 A mophie that I use to recharge my smartphone & iPad. Can I use a mophie or similar power pack to power a breadboard?

According to Wikipedia, the USB standard allows up to 5 amps output.

I didn't see the other thread where "They don't recommend it".
I say using a wallwart is perfectly fine for electronics breadboarding.

You have two options in this regard:

1) Use a 5VDC SMPS that gives 5VDC regulated output.

2) Use an unregulated DC wallwart, e.g. 7-9VDC and use a 7805 three-terminal voltage regulator to give you 5VDC regulated.

 

I would suggest a 5V and a 12V wall wart - perhaps a couple of amps each, to start with. They don't go flat, nothing bad happens if you short them and they are not expensive.

 

I didn't see the other thread where "They don't recommend it".
I say using a wallwart is perfectly fine for electronics breadboarding.

The suggestion was to connect them in parallel or series and it was that which wasn't recommended.

 

The suggestion was to connect them in parallel or series and it was that which wasn't recommended.

Right. It depends on the current and voltage requirements of your project.
I am assuming that a large percentage of hobby projects take no more than 1A @ 5VDC.

Your next likely requirement would be to build a dual DC supply to provide ±12VDC or ±15VDC that could supply no more than 200mA. No reason to go higher unless you really need it.

I have a single wallwart that outputs all three voltages, +5V, +15V, -15V.

Similar to this:

 

I have a single wallwart that outputs all three voltages, +5V, +15V, -15V.

That's very handy!

 

I would suggest a 5V and a 12V wall wart - perhaps a couple of amps each, to start with. They don't go flat, nothing bad happens if you short them and they are not expensive.

You all haven't verbally said no to my question, but I assume that you don't recommend using a mophie or similar as a power source.

A wall wart would be my 1st choice. Batteries would be my 2nd choice. Over time, whether the battery is primary or rechargeable, the voltage will go down. In another post on this forum that I asked about wall warts, the recommendation was a switching mode power supply wart.

I've noticed that wall warts aren't high current. The most that I've seen is 1.8 amps. I have a HP mini netbook AC adapter. It's output is 19V at 1.58 amps. I have a 5V 1.8 amp USB wall wart.

Can I use a laptop AC adapter/charger?

 

A 19VDC @2A laptop charger is a poor choice unless you need 19V @2A.
A linear 5V regulator fed from 19VDC will get very hot very quickly.

You have not said what is your project?
I have used a 5VDC/1A supply for many years for all of my breadboarding needs.

Describe your project requirements and go from there.

 

A 19VDC @2A laptop charger is a poor choice unless you need 19V @2A.
A linear 5V regulator fed from 19VDC will get very hot very quickly.
I don't know what I was thinking!

You have not said what is your project?

I don't have a project, yet.

I have used a 5VDC/1A supply for many years for all of my breadboarding needs.

Describe your project requirements and go from there.

 

I watched some YouTube videos where a USB power bank was used to power an Arduino & a Raspberry Pi. One was also used to power 12V routers.

 

I don't have a project, yet.

So start a project and we'll find you the right power supply.

 

So start a project and we'll find you the right power supply.

I'm anxious to start. I need hardware. I need a soldering station, DMM, breadboard, toolbox, storage for components, etc. I'm window shopping & asking lots of questions on this forum. I'm making room for my new hobby. I'm going thru my apartment, room by room, & whatever I lay my hands on either ends up in the trash or goes to Goodwill or I find a place for it.

 

I'm anxious to start. I need hardware. I need a soldering station, DMM, breadboard, toolbox, storage for components, etc. I'm window shopping & asking lots of questions on this forum. I'm making room for my new hobby. I'm going thru my apartment, room by room, & whatever I lay my hands on either ends up in the trash or goes to Goodwill or I find a place for it.

Go to your Goodwill retail store and look for a suitable AC adapter (wallwart).

You want to look for two types:

1) A small switching power supply that outputs 5VDC regulated, around 1A
2) Unregulated 7-9VDC @ 500mA-1000mA

You can tell the difference by the size and weight.
#1 SMPS will be smaller and lighter.
#2 has an AC step-down transformer and will feel much heavier.

I would get one of each since they are inexpensive, under $5.

Preferably, you want one that uses a standard barrel plug:

The 5V adapter will more likely come with a different plug. You can cut off the plug and replace it with a standard plug.

 

In general, batteries are a terrible choice for bench work.

You already have a lot of things to be thinking about- why add the state of your batteries to the list?

 

I've retired & want to get into electronics as a hobby.

I've wondered about how to power the breadboard. Elsewhere on this forum I asked about connecting wall warts in series or parallel. They don't recommend it. So, I can use batteries or wall warts (but not connected ones!) or adapt a PC power supply. I have a 12 A mophie that I use to recharge my smartphone & iPad. Can I use a mophie or similar power pack to power a breadboard?

According to Wikipedia, the USB standard allows up to 5 amps output.

Overkill on power. By the nature of breadboards (learning and experimenting) high wattage power sources are a danger. It can generate many watts of smoke and flame in an accident. Wall warts or AA batteries are much safer.
Suggested sources:
+5 V, < 500 mA for digital
+V adjustable, < 12 V, < 200 mA for general exercises
+ and - V (5, 6, 9, 12 or 15), 100 mA for analog.
Other voltages and currents only as needed.
Most all applications have current limiting and voltage regulation. Current limiting set just above what I expect the circuit to draw.

Me? I have hundreds of wall warts to suit my needs. (I used to run a school.) I can throw together most any power I need. For higher power, yes, I have a few PC power supplies, too, but only used when needed.

 

In general, batteries are a terrible choice for bench work.

You already have a lot of things to be thinking about- why add the state of your batteries to the list?

I'm thinking the same thing. Whether primary or rechargeable, the voltage on a battery will decrease over time. I researched it & the NiMH has a flatter discharge curve than the alkaline.

I did see a YouTube video where a USB power bank was used to power an Arduino & Raspberry Pi. I have a 12A power bank. I can always use that or batteries as a backup & use wall warts as primary voltage source.

 

I don't understand why they would label a power bank as 12A.

What you should be looking at is the current x hour capacity. For example, if the battery is spec'd at 6000mAh then you can draw 1A for 6 hours. In reality, you want to derate that to about 80% which would give you 1A for 5 hours.

 

I don't understand why they would label a power bank as 12A.

What you should be looking at is the current x hour capacity. For example, if the battery is spec'd at 6000mAh then you can draw 1A for 6 hours. In reality, you want to derate that to about 80% which would give you 1A for 5 hours.

Sorry about that! It's actually 12,000 mAh. I guess 12,000 looks better to the marketers than 12!

This is the one I have:

http://www.mophie.com/shop/universal-batteries/powerstation-plus-xl