Electronics

A collection of technical articles on electronics, or subjects related to electronics. Some of these articles also appear in the "application notes" section.

Since electronics and software are becoming more and more intertwined, you may also want to look in the "embedded systems" section. There is an article on debouncing switch inputs (in software), for example.

These articles are related to the production of printed circuit boards, or to the storage of these boards or components.

Reel quantity estimate

2024-11-24
A simple method to estimate the number of components left on a reel.

Mini-reel for SMD components

2024-12-08
The mini-reel is a reel for SMD components on cut tape. It is compatible with the standard 7" reels (and compliant with EIA-481), only smaller. It is well suited for storing small quantities of SMD components on cut tape.

Mini-tray for SMD components

2024-11-24
The mini-tray is an alternative to the standard JEDEC tray for semiconductors. It is dimensioned such that three mini-trays (when lined up) have the same width & length as one JEDEC tray.

Magnetic PCB holders

2024-11-24
General purpose PCB holders with a magnetic base. The PCB holders lift the PCB a few millimeters from the base, so that they are suitable for (most) PCBs with components on both sides.

Reflow soldering profiles

2024-11-24
With a special focus on the eC-reflow-mate from Eurocircuits, this article delves into the art and craft of creating reflow soldering profiles. The article also covers phenomenons like thermal inertia and their effects on the soldering profile.

Articles on probes and measurement tools and methods.

Near-Field Probes for EMC testing

2024-03-25
The contribution of this article is a 3D-printed insulation sleeve for near-field probes. Along the way, it also explains how to make the probes themselves.

LISN-mate for a dual channel DC LISN (EMC testing)

2024-11-24
A simple but effectice LISN-mate for a dual-channel DC LISN, such as the one published in Elektor. A LISN lets you measure the conducted emissions on power cables; a LISN-mate lets you further establish whether these emissions are primarily “common mode” or “differential mode”.

Articles on design techniques and theoretical concepts.

Parallel Capacitors and the effect of Antiresonance (PDF)

2023-01-31
When multiple capacitors are used for decoupling (which is quite common for micro-controllers and FPGAs, for example), must these all have the same value, or is there an advantage in mounting multiple capacitors with different values in parallel? This white paper presents experiments that demonstrate the effect (and magnitude) of antiresonance when mixing capacitor values. It concludes that, as a rule of thumb, you should keep all decoupling capacitors the same.

Interfacing the VS1053 and VS1063 to DACs and SRCs

2024-11-24
The VS1053 and VS1063 audio decoder chips from VLSI Solutions support I²S output (in addition to analogue audio output). However, the specific I²S format narrows your choice of DAC, SRC or DSP. The simple circuit presented in this application note converts the I²S format from the VS10x3 to 32Fs Right-Justified, which has much wider support by DAC, SRC and DSP chips.

Configuring a micro-controller for low-speed USB communication

2024-11-25
All device controllers that support full-speed, also support low-speed. This is inherent to the protocol. However, since only few programmers have knowledge of the USB physical layer (signal levels), and few circuit designers have knowledge of the programming intricacies, low-speed configuration of an USB device is becoming "lost knowledge". This article fills the void.

Candela, Lumen, Lux: the equations

2019-04-25
There are various measures in use for quantifying the light produced by a light source, such as a LED. This article gives a brief overview of the more important measures and how they relate.
    Most recent update: A paragraph on Luminance (measured in Candela per square metre, or "Nits") is included.

A few simple & useful circuits.

LED current source

2012-05-15
This article presents a circuit for a "constant current source", for example to drive LEDs. The circuit allows the current flow to be switched on and off, with 5V TTL-logic. One way to use the on-off switching capability is to dim the LEDs with pulse-width modulation.

A MIDI to RS232 converter

2024-11-25
The MIDI protocol is a serial data communications protocol using on a "current loop" physical layer, and using a Baud rate of 31250 bps. This article shows the electronics needed to convert between current loop and the RS232 signal levels. The circuit can be connected directly to the RS232 port of the H0420 MP3 player. In the second part, the article covers the "software protocol" of MIDI and develops a simple script to send and receive MIDI commands.

An RS232 "spy" cable

2024-11-25
The RS232 norm defines a one-on-one communication link between two devices. With a special cable, though, it is possible to have a third device (a PC) "listen in" on the data —a useful trick in debugging serial protocols or for deciphering an unknown protocol.

A voltage inverter circuit

2010-04-15
Sometimes you need to generate a negative voltage when you only have a positive power supply. The circuit in this application note does just that. The circuit was built to drive LCDs that require a negative LC-driving voltage.

Miscellanesous articles related to electronics production and design.

ICSP programming tool/adapter

2024-11-24
This tiny adapter enables In-System Programming of the NXP LPC1000 and LPC2000 microcontroller series using the tag-connect cable and an FTDI TTL-232R interface cable. It may also apply to other microcontrollers that use ICSP.

Folding large format technical drawings

2024-11-25
Technical drawings in A3 or larger formats can be rolled or folded (for archiving or sending by post). This article lists the advantages that folded drawings have —provided that they are folded correctly. Then it presents the procedure to fold large format drawings, from A3 to A1.