Check out hardware design guidelines from FTDI when using their ICs. While use of FTDI ICs makes USB easy to implement, care must be taken during the hardware design phase of a project to ensure certain practices are followed. This application note provides design guidelines for several common questions that have been asked of the […]
Category Archives: app notes
Which Switch is Which?
Another great video tutorial on analog switches from LogicHead What is an Analog Switch? Learn how they work and the many different types available to solve all your switching needs
How do I read a datasheet?
Great introduction from LogicHead on what’s inside a datasheet Take a guided tour through a Logic datasheet, and learn where to find the answers to the most commonly asked Logic questions
App note: Universal serial bus power management
See this app note from Micrel on USB power requirements and distribution. Power management and distribution is a major factor in correctly designing USB (Universal Serial Bus) peripherals. Proper methods of designing USB peripheral power distribu- tion are crucial to ensure full compliance with the USB specification, including compliance with electromagnetic in- terference (EMI) and […]
App note: Design considerations for 5V to 3.3V pass regulators
Great app note from Micrel on thermal management for voltage regulators. This note discusses the LDO option, including choosing between simple three terminal regulators and full-featured five terminal regulators, and provides formulas, calculations, and a selection of commercial heat sinks for powering 3.3V logic circuitry requiring up to 5 amps from a standard +5V supply. […]
App note: Interfacing 3V and 5V applications
Another app note from NXP/Phillips Semiconductor on I/O voltage level shifting. Many reasons exist to introduce 3V systems, notably the lower power consumption for mobile applications and the introduction of parts that use technologies with such fine geometries that 5V is simply not allowed any more. The introduction of the 3V standard as supply voltage […]
App note: CPLD timing
See from Xilinx app note the timing constraints on CPLDs. In this application note we will discuss how to constrain a CPLD design and how to verify that the design has met timing. Fundamentally, CPLD timing is the same as FPGA timing; however, the CPLD timing constraints are a subset of the FPGA timing constraints.
App note: Understanding XC9500XL CPLD power
Here’s an app note from Xilinx on calculating power consumption for a CPLD. The goal of this application note is to discuss XC9500XL CPLD power estimation and optimization and provide the reader with an understanding of sense-amplifier based CPLD power dissipation. A brief discussion of the process for estimation is given. With this information, you […]
App note: CPLDs as Motor Controllers
Here’s a simple motor controller implementation using CPLDs from Xilinx. To enable a CPLD to turn the electromagnets on and off, external transistor drivers must be used. A unipolar stepper motor can be driven by four identical NPN or N-channel drive transistors. The various Xilinx CPLDs can operate with I/O voltages from 1.5V to 5V. […]
App note: Xilinx in-system programming using an embedded microcontroller
Program Xilinx’ CPLDs and FPGAs with the aid from this app note. By using a simple JTAG interface, Xilinx devices are easily programmed and tested without using expensive hardware. Multiple devices can be daisy-chained, permitting a single four-wire Test Access Port (TAP) to control any number of Xilinx devices or other JTAG-compatible devices. The four […]
App note: Small, high-voltage boost converters
Produce high-voltages from low input sources as low as 2.5V, Maxim’s app note discusses three topologies and their limitations as well as their advantages on achieving these large voltages. The biasing of avalanche photodiodes (APDs), piezoelectric transducers (PZTs), vacuum fluorescent displays (VFDs), and microelectromechanical systems (MEMS) require high-voltage power supplies. This app note presents three […]
App note: Model of chip cap tombstoning
Here’s a graphical app note from TDK on the phenomenological “tombstone” when doing reflow soldering. If temperature and solder quantity is inappropriate during substrate mounting, products may not be mounted properly, which causes tombstone
App note: Four channel digital voltmeter with display and keyboard
Here’s an old but quite clever approach app note from Microchip on utilizing microcontroller I/O’s to handle multiple display and switches with only few pins. This application note demonstrates the capability of the PIC16C71 and has been broken down into four subsections: • Multiplexing Four 7-Segment LED Displays • Multiplexing Four 7-Segment LED Displays and […]
App note: Temperature measurement using thermistors
Another temperature sensitive device, introducing the thermistor. From its name you could guess that its a temperature dependent resistor which varies its resistance as the temperature changes. See Cypress’ application note on using these devices. A thermistor is a temperature-sensitive resistor in which resistance varies with temperature. There are two types of thermistors: positive temperature […]
App note: Temperature sensing using diode
Last time we covered using watchdog timer as temperature dependent component of a microcontroller to do temperature sensing. Now lets take a diode to do the same thing, they are pretty much accurate and cheap, see Cypress’ application note about its implementation. There are various sensors available for measuring temperature such as Thermistor, Thermocouple, resistance […]
App note: F-RAM for smart E-Meters
Cypress’ application note on smart E-Meters and why its more advantageous to use F-RAM over conventional EEPROMs. This application note provides an overview of a smart electricity meter, or Smart E-Meter, and explains the benefits of using nonvolatile serial F-RAM rather than EEPROM in Smart E-Meter designs.
App note: Tone Generation and Melody Player
Two application guides (Tone generation and Melody player) from Microchip to get you started on tone generation basics, these might help create musical greeting cards to give to your fellow geeks this coming holidays. A general purpose resonator routine is implemented using a PIC17C42. This routine is used to generate multiple tones. A tone signal […]
App note: Rework method for surface mount MLCCs
Things you might need to know about doing SMT rework on Multi Layered Ceramic Capacitors (MLCC). An application guide from TDK Rework is necessary when surface mount (SMT) components become misaligned or improperly mounted. This paper will answer questions concerning rework of SMT capacitors. Specifically, equipment, procedures, and technique are covered.
App note: properties and application of bypass capacitors
Another primer app note from NXP on capacitor bypassing. Bypass capacitors are applied between the power supply pins VCC and GND of integrated circuits. They reduce both the power supply noise and the effect of spikes on the supply line. They also provide instantaneous current demands of the integrated circuit as it switches. This application […]
App note: LCD biasing and contrast control method
Application note on direct Liquid crystal display driving using PIC microcontrollers. This Application Note provides methods that can be used to provide biasing voltages for Liquid Crystal displays. This document covers most of the biasing methods used in the PIC microcontrollers with an LCD controller.