App note from Maxim Integrated guiding you when selecting voltage references. Link here What could be more basic than a voltage reference – a simple, constant reference voltage? As with all design topics, there are tradeoffs. This article discusses the different types of voltage references, their key specifications, and the design tradeoffs, including accuracy, temperature-independence, […]
Author Archives: DP
App note: Voltage Reference Application and Design Note
App note from Renesas on the basics of voltage reference. Link here (PDF) Conceptually, a voltage reference is a very simple device with only one purpose in its life. Quite simply, the purpose of a voltage reference is to generate an exact output voltage no matter what happens with respect to its operating voltage, load […]
DIY OpenDPS power supply
Evan’s DIY OpenDPS power supply: Years ago I heard about the OpenDPS project to give open source firmware to cheap and available chinese power supplies. These aren’t strictly whole power supplies, they are configurable CC and CV buck converters. That means that it needs a stable DC source to back it to be used as […]
Arduino OLED display shield
Florinc posted his Arduino OLED display shield project: The 2.4″ I2C OLED display I had sitting idle is too big for the “Promini OLED Clock shield”, yet a perfect candidate for a regular Arduino shield. This is how it looks soldered on a prototype shield with two buttons on top, attached to wsduino running the […]
App note: How to monitor state-of-charge in small batteries with tiny, ultra-low-power comparators
App note from Maxim Integrated about low current and voltage battery monitors. Link here Many of today’s portable consumer electronic devices are powered by small button or coin-cell batteries. Users, of course, expect long battery life and reliable charge-level information. However, it can be quite challenging to efficiently monitor the health and state-of-charge (SOC) of […]
App note: Effects of different resistor tolerances in a differential ADC for THD performance
App note from Maxim Integrated demonstrating the effects of different resistor tolerances on the analog front end of ADC’s performance. Link here This application note explains how the different tolerances of the same value resistors at the inputs can alter the THD performance of the fully differential ADC. The cost of resistors changes significantly with […]
How to make a very cheap VHF receiver
Sverre’s cheap VHF receiver: What is the cheapest receiver you can make for VHF? Here is a candidate where all you need to do to modify a small FM headphone receiver is to desolder one end of two capacitors, and connect a short cable with an antenna connector. See the full post on LA3ZA Radio […]
(Not a) triple tube geiger counter
Doz’ triple tube geiger counter project, that is available on GitHub: So, two little switching power supplies, one for the DOB-50 and CTC-5 as they have similar operating voltages, and one higher voltage one for the DOB-80, a simple op-amp comparator to output the pulses to an Arduino to process and display the results. The […]
App note: LV5980MC step-down switching regulator
Single chip high efficiency step-down converter, app note from ON Semiconductors. Link here (PDF) The LV5980MC is a fixed 370 kHz, high−output−current, Non−synchronous PWM converter that integrates a low−resistance, high−side MOSFET and a Customer Chosen, External Diode for the rectification. The LV5980MC utilizes externally compensated current mode control to provide good transient response, ease of […]
App note: Designing a PSR Quasi-Resonant adaptor driven by the NCP1362
ON Semiconductor’s app note featuring 12V 12W adaptor design using NCP1362 primary side regulation controller with valley lockout that hold its switching frequency at light loads. Link here (PDF) Quasi−square wave resonant converters also known as Quasi−Resonant (QR) converters are widely used in the adaptor market. They help designing flyback Switched−Mode Power Supply (SMPS) with […]
A new, fully modular CNC controller
bdring’s new universal CNC controller for Grbl_ESP32 , that is available on Github: The blog post details a new CNC controller I designed. I have probably designed 40-50 different controllers over the years, but this one has me really excited. My past controllers were generally application specific. My recent controllers have all been for the […]
The Hayes Chronograph, a remake for 2020
smbakeryt built his own Hayes Chronograph: I’ve always wanted a Hayes Chronograph, but have never been able to acquire one, so I finally broke down and just made my own. The Hayes Chronograph was a compliment to Hayes line of smart modems, and implemented a real time clock for computers that didn’t have a built-in […]
μSim: PICmicro instruction simulator
Dilshan has published a new build: μSim is a lightweight PIC™ CPU and ALU simulator. This simulator supports the PICmicro mid-range instruction set and designed to work on both PC and Arduino platforms. Compare with most of the other emulators, μSim does not provide all MCU features and peripherals. This simulator design as a minimalistic […]
App note: FT90X ethernet LED control
App note from FTDI/Bridgetek demonstrating LED control over Ethernet. Link here (PDF) In an increasingly connected world, more and more devices are going online. To enable online connectivity typically requires an MCU with Ethernet or Wi-Fi capabilities. To demonstrate the principle, this Application Note describes an implementation of a web server which allows for control […]
App note: FT93x RTC external power switch circuit
App note from FTDI/Bridgetek on simple implementation of external power switch for RTC power hand-over. Link here (PDF) The Texas Instruments SN74AUC2G53 Single-Pole Double-Throw (SPDT) analog switch is used to select the power supplied by the 1.5V battery or by the 1.2V internal LDO.
100 MHz third overtone crystal oscillator
100 MHz third overtone crystal oscillator @ DIYfan: Couple of years ago I purchased from a local store 100 MHz crystal resonator and tried several times to make a working schematic on breadboard using standard circuits I found on the internet. It never worked good enough, usually oscillating at 33.3 MHz instead of 100 MHz. […]
Chaac weather station
An update on Chaac weather station project we covered previously: With this latest redesign, I made a few more changes. First of all, I decided I would no longer be afraid of LoRa and put in a LoRa radio module. This will, with the right firmware, allow for standalone operation using LoRaWAN and The Things […]
A different power source for field ham radio operating
Gwen, NG3P, has been working on a power source project for field ham radio operating: We’re coming up on a confluence of two things: Nice weather, and relaxing of the Covid-19 lockdowns in much of the United States. This means more hams leaving their home shacks and taking their operating to the field. For some, […]
App note: PCB layout guidelines for high frequency signaling products
High speed board design app note from ON Semiconductor. Link here (PDF) There is an increase of devices and circuitry in usage of high speed, low consumption, small volume and lower interference. Hence PCB design is an important stage of electronic product design. It forms a connection between function and electronic components, and is also […]
App note: Calculating and interpreting power dissipation for polypropylene film DC-link capacitors
Tech note from Vishay on polypropylene film capacitor value calculation with temperature and power dissipation consideration. Link here (PDF) Film capacitors can deliver high power density due to their low ESR and high ripple current capabilities, and offer the highest ampere per μF ratio of capacitor technologies. This feature, combined with their high reliability and […]