Maxim describes how to design PCBs for DC/DC switching power supplies. Learn which traces to keep as short as possible, and the reasoning behind it. The diagram sums up our own approach nicely as well. When working with any buck or boot converter, we: Keep the main power path (shown in blue) straight and compact. […]
Category Archives: app notes
App note: PC fan control using an ATtiny13
Dumb PC fans come with 3 pin jacks, and have no PWM control. This app note explains how to make a “smart” fan from a “dumb” one by implementing PWM control using an ATtiny13 microcontroller. This application note describes the operation of 12 volt DC cooling fans typically used to supply cooling air to electronic […]
App note: Touch-screen technologies roundup
Common touch-screen types are resistive, capacitive, or haptic. This app note describes each: Touch screens are not a new concept. Where previously touch screens were merely designed to replace keyboards and mice, today they convey a completely new operating experience. Featuring greater interaction between the user and device, this new “touch” experience has been achieved […]
App note: An applications guide for operational amplifiers
Here is a application guide from Texas Instruments is an overview of operational amplifier-related circuits, theory, and formulas. Inverting amplifiers, buffers, analog adders, filters, and many more are covered. The general utility of the operational amplifier is derived from the fact that it is intended for use in a feedback loop whose feedback properties determine […]
App note: Tips ‘n tricks for comparators in PIC microcontrollers
A collection of tips and tricks from Microchip for using the comparator module on PIC12F and PIC16F microcontrollers. These peripherals usually have high propagation delays, but many applications don’t require high response times from the microcontroller. This app note outlines 20 different applications where integrated comparators might come in handy, such as low battery detection, […]
App note: General layout guidelines for RF and mixed-signal PCBs
Rsdio came across an interesting app note from Maxim and shared it with us. These are some PCB layout guidelines for RF and mixed-signal designs. This application note provides guidelines and suggestions for RF printed-circuit board (PCB) design and layout, including some discussion of mixed-signal applications, such as digital, analog, and RF components on the […]
App note: LM5022 DC/DC boost controller
Here is a part from National Semiconductor designed for controlling high-power DC/DC boost regulators. What makes it interesting is that its PWM frequency can be pushed to 2Mhz. This allows for smaller and cheaper discrete components, like inductors and capacitors. The datasheet on this device also provides some nice PCB guidelines to maximize its efficiency […]
App note: Control LED brightness with buttons.
Maxim shows how to build a LED brightness controller with 64 level of control using push buttons. The design incorporates a current regulator that is driven by a 64 tap digital potentiometer. The buttons increment and decrement the tap. Via Electronics-Lab.
App note: Thermocouple measurement
Last week we wrote about a Maxim app note about high precision temperature measurement with thermocouples. At Jim’s request we found a more in-depth intro to thermocouples. This app note from Linear Technology covers everything you ever needed to know about thermocouples. Learn how thermocouples were discovered, and how to build very elaborate and highly […]
App note: DMX512 isolated receivers using digital capacitive-isolation technology
Here is an app note from Texas Instruments describing in depth how DMX512 protocol functions, and how to build isolated DMX512 receivers. Their new isolated transceivers use digital capacitive-isolation technology, which has proven to be more reliable, and resilient, then the opto-isolation that was common in DMX512 devices. This type of isolation has been tested […]
App note: Comprehensive manual for SMD components
Here is a comprehensive manual for SMD components. It covers most common SMD components used in the electronics industry today. Package dimensions as well as markings are covered. This brochure brings a help and clearance for a newcomer and moreover should help a service technician to start a repair of the instruments made with the […]
App note: High precision temperature measurement with thermocouples
The sensitivity of modern thermocouple is around o.1C over a range which spans from -270C to 1750C. Here is an app note from Maxim on how to built high precision temperature acquisition systems based on thermocouple sensors. One examples uses a 24bit ADCs for high precision measurement. Another example use a MAX31855 thermocouple-to-SPI converter for […]
App note: Understanding ADC specifications and attributes
Here is an app note from Microchip explaining how to interpret various analog to digital converter specifications. This article covers how attributes of ADCs are calculated and how they apply to it’s performance and precision. The purpose of this application note is to describe the specifications used to quantify the performance of A/D converters and […]
App note: Logic-level translation
Here is an app note from Maxim describing how to implement level translation when faced with two systems that operate at different voltages. The article describes methods for accomplishing logic-level translation varying from very simple circuits using only a few discrete components, to circuits using a single dedicated IC. Electronic design has changed considerably since […]
App note: Opto-isolating the I2C bus
Isolation is important if you need to separate two circuits completely, leaving no possibility of an electrical problem in one causing an problem in the other. The most challenging digital circuits to isolate are bidirectional data lines like the I2C bus. In this EETimes editorial the opto-isolation of the I2C bus is covered in detail. […]
App note: Electrically isolating a USB device from the host
The Analog Devices ADUM4160 isolates and protects a computer from shorts, high voltage, or high currents in a USB device. The isolator chip sits on the D+ and D- data lines between the USB jack and the microcontroller on the USB peripheral. Unfortunately it doesn’t come cheap at more than $5, but it could save […]
App note: Guidelines for soldering QFN lead-less packages
This app note from Texas Instruments covers the basic guidelines on how to solder QFN and SON lead-less package. It includes some PCB design, solder paste screen printing, assembly, and reflow guidelines. Quad flatpack no leads (QFNs) and small-outline no leads (SONs) are leadless packages with electrical connections made via lands on the bottom side […]
App note: Detecting and locating RF bugs
We wrote about a phone bug in a previous post. Here’s an app note about a circuit for detecting and locating radio frequency transmitters. This design idea showcases a circuit that detects RF “bugs,” such as hidden wireless cameras, eavesdropping microphones, and other spying devices that emit RF frequencies in the 100MHz to 3000MHz range. […]
48 ways to use a charge time measurement unit
The Charge Time Measurement Unit (CTMU) found on some PIC microcontrollers is a peripheral to interface with capacitive touch sensors. It can also be used in other functions, and the app note linked above provides a few ideas: In a nutshell, the CTMU is an on-chip constant-current source, surrounded by digital circuitry to precisely control […]
App note: dsPIC33E simultaneous analog sampling
Some new PIC 33E and 24E microcontrollers can take simultaneous samples from multiple analog to digital converters. Most chips measure analog values sequentially, but this ADC can sample 4 signals at once. Samples are still converted one after the other, but they’re collected at the same moment. More in the reference manual for dsPic33E and […]