Welcome to a new video, today I’m building a bunch of usb to serial converter boards because if you are into electronics and microcontrollers you will for sure need a bunch of usb to serial converters to connect your boards to a computer for example.
The idea for building these boards started when I found the CH340E converter chip on aliexpress, I like several things about this chip, it was small because it comes in MSOP10 package, it was cheap at about $0.40 a piece and it requires minimal external circuitry, in fact it only needs an external bypass cap.
Welcome to a new Voltlog, in this video I’m gonna show you how I designed and built this board which functions as an esp32 based, battery powered PIR motion sensor. So I started by designing the circuit, I used some common building blocks, I added the ESP32 with it’s bypass caps, some test points and the programming circuit with auto-reset, I then added some connection points for the PIR sensor, an RGB LED because why not have a nice way to signal this is one of those very small digital RGB leds, it’s just 20x20mm, it’s connected to 3.3V even though it’s only rated for 5V so I’m hoping this is going to work even on 3.3, it’s also worth having a temperature/humidity sensor to also sense that in whichever room the node will be placed and finally the power supply circuit which is a simple low dropout regulator with an 18650 battery as the input.
I did not include a battery charger circuit on this module, because I wanted to keep things simple, I’ll have a battery socket so I can just remove the 18650 cell and charge it separately plus the whole circuit should run in sleep for extended periods of time giving me a long operating time so i wouldn’t have to charge the battery too often.
Once the schematic was finished I did the board layout in a hurry so it’s not exactly pretty or optimized
but I tried to move the esp32 antenna to the side, to place the PIR sensor in the top side as the module will probably sit vertically, I tried to place the temperature sensor in the bottom side to keep it away from any components that might get hot and also placed some isolation slots for the same reason.
You should check-out revB of this board, I made some improvements present in the video below.
Welcome to a new voltlog, the series that will touch both your passion for electronics and your bank account at the same time. We’re gonna start the video with a battery charger from Liitokala, model number is Engineer Lii-500. It works with an external 12V power supply which I opted not to get because we all have a bunch of 12V adapter from old equipment.
Welcome to a new voltlog, the first one in 2019 and what better way to start the year than with a InTheMail video the series that will touch both your passion for electronics and your bank account at the same time. As some of you might know I’ve recently created my patreon page so for those that would like to support me making these videos, you will find a link the description below, any pledge amount is appreciated, even 1$, just imagine half of my subscribers pledging 1$ a month. And if you can’t offer any donations, that’s fine too, my content will continue to be free.
Links for all of the items shown in the video will be in the video description, on youtube.
Welcome to a new Voltlog today we are taking a closer look at this inexpensive speech synthesis module. The part number is XFS5152CE and we do find a datasheet for this chip but unfortunately it is all in Chinese. The datasheet contains schematic examples, they show you how to wire a microphone pre-amp, how to wire an audio amplifier, they also give you some code examples but most of the text is in Chinese.
I found this online doc translator service which worked surprisingly well, it translated my document and kept most of the formatting intact. So now I have a translated datasheet which I will link in the description below and I will also place a link to places where you can buy this module and also where you can buy just the chip.
This is just a short follow-up on the e-paper display video. It was brought to my attention by one of the viewers that banggood is shipping the bare display instead of the module as whole display + pcb + cable.
In this video I’m gonna show you how to load a custom image on the e-paper display. Let’s see how easy it is to get started working with one of these e-paper display modules and an Arduino board.
Welcome to a new InTheMail, the series that everybody seems to like, seriously I’m thinking this is starting to look like some group meeting where we all have the addiction to keep purchasing cheap electronic stuff from China.
Here is a list with the items shown in this video:
SG3525A PWM generator module
Photocell Automatic On/Off Light Switch Relay
B0505S-1W Isolated 5V DC-DC Converter
5V 2A DC-DC Converter USB Charger With Voltmeter Module
5V 3A DC-DC Converter USB Charger Module
12V 0.5A AC-DC Switching Power Supply Module
LCD1602 I2C Serial Interface Adapter Module
WS2812 RGB LED Controller
WS2812 RGB LED Strip PCB Module
You can find links to all of these items in the video description visible on youtube.