With Instructables you can share what you make with the world, and tap into an ever-growing community of creative experts.
Low power door/window sensor
Welding Gloves That Live Forever
Solar Water Heater from scratch
Garden hose adapter for IBC...View Instructable »
By the way, for certain values of the variable resistor, this Dell power supply will shut down it's output and will not turn it on again unless you disconnected it from the mains (in advance you need to rotate the variable resistor to a suitable value). For sure it was designed to provide a fixed voltage with a good efficiency and maybe a modification of + / - 4 Volts can be ok, but to have a nice variable power supply, not really. But for such mods, BeachsideHank made a useful comment about using a linear regulator :) (I think there are as well Instructables on this)
Thank you for your feedback! I wanted to check for myself the formula (on this Dell power supply it is Vout = 2.5 x (R41 + R42||R42A) / (R42||R42A) ). I used values of the resistors on board (see my schematic from the Instructable) and the output voltage (19,5 Volt), I expected to calculate 2.5 Volt from the voltage divider at the VSENSE pin, since this will be compared with the internal 2.5 Volt reference. (R42 || R42A = 1996 Ohm). Voltage divider output (R41 and R42||R42A) for 19.5 Volt input is 0.556 Volt. For a certain frequency, R41 is parallel with R41A, in that situation divider output is 17,17 Volt. Not sure why.
Thank you for your feedback!
Thanks for your feedback! This effort was mostly on mechanical side, on the electronics was less effort. I think this was the reason: somewhere on the circuit I have only to replace a single resistor without considering the mechanical part of the project. This modified power supply will serve my Lithium charger only and can supply around 4 Amps max, while linear regulators can supply less current, have voltage drop on them, need extra heat sink, need a case too. I used a linear regulator for a bench power supply.
Modify a Dell laptop power ...View Instructable »
Thanks for your feedback, it may work what you are saying. You can provide the correct voltage using 5 volt USB and a regular diode and using the USB charger you should be able to give a certain amount of current. Also you need to keep an eye on a clock, divide battery capacity to the current provided by USB charger to see how much time is needed to let it charge. One I'll experiment this:)
Thanks for your feedback, I agree about lipos from ebay, you can pay a few dollars for a 6000 mAh :) I use recovered 18650 from laptop batteries. Regarding the electronics I used, that micro USB module may fail as well, but I trust it since I am using this for a while and on the other hand the voltage is lower.
Thank you for your feedback :)
Thank you for your feedback, I added an important-missing link - there is an youtube video and there you can find a good explanation on how this module work. Basically it will take care on the Lithium cell (single cell), it will charge it and will discharge it on the given specs of the Lithium.
Simple RC Stick Plane Build(CAD Model Included)
What is the exact damage done to the board? I am not sure that I understood what is fixing your method. Initially I thought that you had an overvoltage and damaged the micro and the only way is to replace it :)
Liquid Level Capacitive Sensor
Interactive Menus for your project with a Display and an Encoder
Micro USB Lithium charger f...View Instructable »
Pallet hammock stand
FreeRTOS 01 : Setting Up FreeRTOS on Arduino
Introducing LoRa™ !
Arduino LoRa Sensor With InAir9B Radio
Arduino Project: Test Range LoRa Module RF1276 for GPS Tracking Solution
How to make an Universal DC Motor Speed Controller
Old PC Recycled Regulable Power Supply
Wi-Servo: Wi-fi browser controlled servomotors (with Arduino + ESP8266)
Triple Your Tool Storage Space!
Making Simple PVC Flutes
PVC "Mouse Ear" Tool Clips
Make a Wood Carrier that's a Cinch
Mini weather station with Attiny85
A Radiant Solar Food Dehydrator that doesn't fight physics - GeoPathfinder.com
IoT ESP8266 Series: 1- Connect to WIFI Router
Drawing instructables robot by Mini CNC - Arduino - L293D Shield
Display YouTube Stats on a 320x240 Pixel LCD Screen Connected to an Arduino Uno
Using an ESP8266 to Control Mains Sockets Using 433mhz Transmitter and Receiver
Remote Temperature Monitoring Using MQTT and ESP8266 Modules
How to Make Arduino Battery Shield
How to Program an ATtiny 85 Digispark
15 Projects for Raising Backyard Chickens
Rainfall Measurement System for a Beehive
Simple Home Weatherstation
Arduino IOT: Temperature and Humidity ( with ESP8266 WiFi)
RFM69 / Arduino Pro Mini Having Lively Discussion with JeeLink
Steps to Setup Arduino IDE for NODEMCU ESP8266
A Great Bending Tool for Solid Material
Bath tub makeover
Improved Arduino Rotary Encoder Reading
Weather Station 5
Simple Belt Sander Blocks
Touch Screen coffee table DIY with 32" TV and low cost CCD sensor
Hand-Drawn Voronoi Diagrams
MFT My Fabulous Table
Hand drawn picture style in Gimp
Raspberry Pi photo booth controller
Angle Divider for Perfect Miters
Remote Wi-Fi DHT11 Temperature and Humidity I2C 2 X 16 LCD Display With Two ESP8266 and Visuino
Bed in a Box
Self-Marking Tape Measure
Build a DIY Desktop 3d Scanner with infinite resolution.
Arduino keychain camera modify to motion detect camera
Raspberry Pi + Node.js + Blynk App + DHT11/DHT22/AM2302
Vulcanus MAX - CoreXY Aluminum Frame 3D Printer Scale UP
Raspberry Pi DropCam Alternative
perfect pumpkin pie spice recipe
Smartphone Fundus Camera
Pallet Coat Rack
Join 2 million + to receive instant DIY inspiration in your inbox.
© 2016 Autodesk, Inc.