Modernizing a laptop bench power supply @ZakKemble

Zak Kemble posts on Zak’s Electronics Blog:

Many years ago (September 2009) I made a simple bench power supply using an LT1083 7.5A linear regulator with adjustable output voltage designed to be used with a 19.5V 3.42A laptop power supply. It still works fine after years of abuse, but my choice of output power connectors was poor (3 pin headers, the sort used for PC fans), it’s made on strip board and cooling was sometimes a problem, so time for an upgrade!

The old power supply also had a selector jumper for 6 voltage ranges; 3V, 5V, 7V, 9V, 12V and 19V. I think I’ve only ever used the 5V, 12V and 19V ranges, so that’s all the new power supply now has.

The new supply uses modern components while still keeping true to the simplicity of the original supply.

See the post for all the details.


Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here: adafruit.com/editorialstandards

Join Adafruit on Mastodon

Adafruit is on Mastodon, join in! adafruit.com/mastodon

Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.

Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7pm ET! To join, head over to YouTube and check out the show’s live chat – we’ll post the link there.

Join us every Wednesday night at 8pm ET for Ask an Engineer!

Join over 36,000+ makers on Adafruit’s Discord channels and be part of the community! http://adafru.it/discord

CircuitPython – The easiest way to program microcontrollers – CircuitPython.org


Maker Business — Making sure the CHIPS act isn’t just crumbs

Wearables — And now a word on laser ettiquette

Electronics — Capacitor ESR

Python for Microcontrollers — Python on Microcontrollers Newsletter: CircuitPython 8.1.0 and 8.2.0-beta0 out and so much more! #CircuitPython #Python #micropython @ThePSF @Raspberry_Pi

Adafruit IoT Monthly — Guardian Robot, Weather-wise Umbrella Stand, and more!

Microsoft MakeCode — MakeCode Thank You!

EYE on NPI — Maxim’s Himalaya uSLIC Step-Down Power Module #EyeOnNPI @maximintegrated @digikey

New Products – Adafruit Industries – Makers, hackers, artists, designers and engineers! — New Products 5/31/23 Feat. Adafruit NeoDriver – I2C to NeoPixel Driver Board – Stemma QT!

Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !



No Comments

No comments yet.

Sorry, the comment form is closed at this time.