Here is a comprehensive guide to operational amplifiers from Texas Instruments. It contains most of the things you ever wanted to know about designing with op amps. History, design examples, and theory is all covered by this guide. Via Electronics-Lab.
Category Archives: app notes
App note: Enhancing ADC resolution by oversampling
Atmel describes how to enhance ADC resolution by oversampling the signal and averaging the extra data. This has a side effect of increasing the signal to noise ratio, and reducing the quantization error. When the ADC samples a signal, it quantizes the signal in discrete steps. This introduces some error, often referred to as quantization […]
App Note: Comparing digital and mechanical potentiometers
Microchip compares mechanical and digital potentiometers to digital. This app note explains the theory behind both versions, and their advantages and disadvantages. Mechanical potentiometers have advantages in terms of having a wide variety of values available and tighter specifications such as nominal resistance, tolerance, temperature coefficient, power rating and temperature range specifications. But in many […]
App note: Basic features of the Atmel XMEGA Direct Memory Access Controller (DMAC)
Here is an app note describing how to use the Direct Memory Access Controller found on Atmel’s XMEGA microcontrollers. This application note covers the basic features of the Atmel XMEGA Direct Memory Access Controller (DMAC). The goal for this training is to getting started with simple memory transfers almost without using CPU time, and reading […]
App note: Lowering power consumption on PIC microcontrollers
Microchip presents several of techniques for lowering the power consumption of their PIC microcontrollers and dsPIC digital signal processors. Many things can apply to any low-power project. This document seeks to simplify the transition to low-power applications by providing a single location for the foundations of low-power design for embedded systems. The examples discussed in […]
App note: Current controlled boost driver for long LED strings
This reference design from Maxim is a current controlled boost driver designed for long strings of LEDs. Driving many LEDs in series has advantages over driving them in parallel. In a parallel configuration each LED will need it’s own current limiting resistor or current control, while the series LEDs make use of a single current […]
App note: Analog and digital conversion handbook
Ultrasounder let us know about this free online data conversion handbook from Analog Devices. It covers everything you’ll need to get started with analog-to-digital and digital-to-analog converters. It’s not just reference designs, but also theory on how various architectures function. The Data Conversion Handbook, edited by Walt Kester (Newnes, 2005), is written for design engineers […]
App note: Porting the Helix MP3 decoder to PIC32MX microcontrollers
Microchip shows how to port the open source Helix MP3 decoder algorithm to the PIC32MX family of microcontrollers. This algorithm was designed be used by both floating point processors, and fixed point processors like the PIC32. Application note describes the procedure to port the open source Helix MP3 decoder algorithm onto Microchip’s PIC32MX 32-bit microcontrollers […]
App note: PCI Express gen 1/2/3 clocks
SQKYbeaver found a PCIe clocking solution from Silicon labs the he thinks can be hacked into a precision clock generator with multiple outputs: The Si52144 is a spread-controlled PCIe clock generator that can source four PCIe clocks simultaneously. The device has four hardware output enable control inputs for enabling the respective differential outputs on the […]
App note: Sense multiple pushbuttons using only two wires
A 1-Wire port expander can be used to sense 8 push-buttons with only 2 wires. It can be powered via a strong pullup on the data line, so a separate power line isn’t needed. For applications that require less than a keyboard or numeric keypad, this simple circuit monitors multiple pushbutton switches using a single […]
App note: Texas Instruments’ standard linear guide
Texas Instruments puts out a selection guide for their op-amps, comparators, data converters and interface ICs. Most manufacturers have these, and they can be a big help when you need to substitute a no longer available linear component in design. Thanks rsdio!
App note: Designing the oscilator circuit for PIC microcontrollers
Here is an app note from Microchip describing how to design oscillator circuits for your PIC projects. The article advises designers to think about the conditions the project will be used in and design their oscillator circuits accordingly. Also provided are examples how to test and tweak the oscillator circuit to get the best result. […]
App note: Using hardware SPI on XMEGA microcontrollers
Here is an app note from Atmel describing hoe to use the SPI module on their XMEGA microcontrollers. Also provided are source code examples for implementing both interrupt driven SPI communication and the polled method for slave and master devices. SPI is a full duplex interface, and at a low cost enabling high-speed communication between […]
App note: Implementing a 9-axis sensor fussion on the MSP430F5xx using the Direct Cosine Matrix algorithm
Here is an app note from Texas Instruments explaining how to implement the Direct Cosine Matrix algorithm on a MSP430F5xx to integrate date form 3 sensors. A magnetometer, gyroscope, and a an accelerometer were integrated to provide a 9-axis sensor. When creating an AHRS, also known as Magnetic, Angular Rate, and Gravity sensor (MARG), a […]
App note: Soft-Start in LED lighting
Using constant current to drive LEDs is a good practice, but turning them on instantly can be dangerous for both the LED and the LED driver. Harmful spikes are generated when large currents are instantaneously turned on. This app note from Maxim describes how to soft start LEDs to increase overall lifetime and performance. An […]
App note: ATXmega USB Hardware Design Recommendations
Here is an design recommendation from Atmel about implementing USB on AVR XMEGA microcontrollers. The article provides all the basic information you’ll need to get started with designing USB devices with the XMEGA. This document is written for hardware designers to help them develop their applications. It assumes that readers are familiar with the AVR […]
App note: Lamp dimmer using PIC12C508
Here is a reference design from Microchip describing how to built a Light dimmer with a PIC12C508 and a few discrete components. The circuit uses a simple zener voltage doper, to drop the voltage from mains to 5V required by the PIC. Watch out, there is live mains voltage involved. This reference note describes an […]
App note: Protect your batteries from reverse insertion
Rsdio tipped us to an app note from Maxim describing how to protect your Lithium Ion batteries from reverse insertion into the charger. The circuit is a Li-Ion battery charger with an added analog comparator designed to detect when then battery is inserted the wrong way and disconnect it from the charger. Combining a linear-mode […]
App note: PCB design perfection starts in the CAD library
This 19 part tutorial shows how to design CAD library parts that make PCB design easier. Part one is a white paper, while the other parts are written as editorials on his blog. If you are serious about building up a part library this is definitely worth a look. The CAD library is the starting […]
App note: Noise sources in low dropout (LDO) regulators
Looking for a clean power supply for a sensitive analog circuit? Analog Devices describes the sources of noise in LDO voltage regulators, and provides some examples to limit and combat the noise. In general, LDO noise comprises two components: intrinsic, or internally generated noise, and extrinsic, or externally generated noise. Thermal and 1/f noise are […]