Tag Archives: app note

App note: Power supply over-current and over-temperature protection

Next up in our power supply theme is over-current and over-temperature protection for power supplies. The circuit cuts power in case one of these two events happen, it also has an external shutdown pin so the supply can be controlled by a switch or microcontroller. When it is necessary to plug in a board into […]

App note: Current limit circuit for buck topology switching regulators

Here’s a current limiting circuit for buck topology switching regulators. This design monitors a shunt resistor and overrides the feedback pin of the switching regulator when the current limit is reached. A current limit can be added to a step-down converter by using a MAX4173H current-sense amplifier to inject current into the feedback network. D1 […]

App note: Thermal characterization of IC packages

Here’s a tutorial from Maxim describing the thermal specifications in IC packages. All the devices used in a project dissipate heat, and if not properly cooled they will fail. This article will bring you closer to understanding the thermal specs quoted in datasheets. Thermal characterization of packages is critical for the performance and reliability of […]

App note: Driving capacitive loads fast by paralleling op-amps and transmission lines

Here’s a video from Linear Technology describing how to drive capacitive loads fast. The proposed solutions is to use multiple op-amps in a parallel configuration to achieve the high-speed requirements. Certain video and other technologies require driving planar conductive surfaces fast. Unfortunately, the surfaces can have high capacitance, which means that driving them fast takes […]

App note: Using thermistors in temperature tracking power supplies

Here’s a tutorial from Maxim describing thermistors and how to use them in temperature tracking power supplies. Thermistors are resistors whose resistance changes with temperature, increases with PTC type and decreases with NTC. This article provides a simple, intuitive tutorial on negative temperature coefficient (NTC) thermistors and how to make basic use of them in […]

App note: Energy harvesting applications with the LTC3588

Here’s a video from Linear Technology describing how to power microcontroller systems with Piezoelectric energy harvesting power supply IC LTC3588-1. It incorporates a full bridge rectifier, and a switch-mode regulator into one IC. New developments in ultralow power microcontrollers with their high level of integration are enabling monitoring systems which draw sub milliwatts of power. […]

App note: Similarities of Wave Behavior

Here is a video from the Bell Laboratories archives. It describes the similarities in wave behavior in all mediums, be it electric, sound, or mechanical. On an elementary conceptual level, this film reflects the multifaceted scientific hyperthinking that was typical of a Bell Labs approach. Host Dr. J.N. Shive’s presence as a lecturer is excellent […]

App note: Detecting human falls with 3-axis accelerometers

Here is an article from Analog Devices discussing the theory and application of detecting human falls with 3-axis accelerometers. While the article focuses on the ADXL345 3-axis accelerometers, the theory and principle behind it can be applied to other devices as well. This article, based on research into the principles of fall detection for an […]

App note: Matching MOSFET drivers to MOSFETs

Here’s an app note from Microchip detailing how to match MOSFET drivers to MOSFETs. There are many variations of MOSFETs out there, and matching one to your driver and vice-versa is essential to getting the most out of your system. This Application Note discusses the details of MOSFET driver power dissipation in relation to MOSFET […]

App note: DC to DC converter tutorial

Here’s a tutorial from Maxim on DC to DC converter design. Buck, boost, inverting and flyback topologies are covered. Diagrams, equations, and control techniques are available for these four common topologies. Switching power supplies offer higher efficiency than traditional linear power supplies. They can step-up, step-down, and invert. Some designs can isolate output voltage from […]

App note: Minimizing switching regulator residue in linear regulator outputs

Jim Williams from Linear Technology explains how to battle switching regulator residue in linear regulator outputs. If you want to clean up the switching regulator output by using a linear regulator, you’ll run into difficulties. Linear regulators are not very good at suppressing high frequency noise, and switching regulators output loads of it. The “secret […]

App note: Difference amplifier vs. current-sense amplifier for high side current measurement

Here’s an article from Analog Devices detailing the differences between current-sense amplifiers and difference amplifiers in high side current measurement. Current sense amplifiers offer measurement of the instantaneous current, while difference amplifiers offer average current measurements.  While current-sense amplifiers offer better current consumptions and lower noise, the difference amplifiers are more robust. Both types of […]

App note: Calculating power dissipation of MOSFETs used in high-power switching supplies

Here’s an app note from Maxim describing how to calculate power dissipation of MOSFETs used in high-power switching supplies. The article is focused on CPU power supplies which operate at lower voltages (0.9-1.75v) but require loads of current (+60A). This article provides step-by-step instructions for calculating the power dissipation of these MOSFETs and determining the […]

App note: Video playback and streaming with PIC32 microcontrollers

Here’s an application note from Microchip describing how to implement video playback, and streaming on PIC32 microcontrollers. The article is written around the Multimedia Expansion Board which features an LCD graphics controller, but it’s enough to grab the basic concepts for your own design. This application note describes four methods of playing a video file […]

App note: Transform a DC/DC converter into a full-featured battery charger

Here is an application note video from Linear Technology describing how to use their LTC4000 coupled with a switch mode regulator to charge batteries. This IC is a supervisory circuit that controls the feedback pin of a switching regulator. It provides the project with safe charging, and seamless switching from battery power to regulator power.

App note: Nine often overlooked specifications in analog to digital converters

Here’s an app note form Analog Design describing the nine often overlooked parameters of analog to digital converters, and how they impact the design. The article goes over the resolution, power supply rejection (PSR), common-Mode rejection (CMR), the clock slew rate, aperture jitter, aperture delay, conversion time and conversion latency, wake up time, output loading, […]

App note: Using UART to implement a 1-Wire bus master

Here’s an app note from Maxim describing how to implement a 1-Wire bus master using the UART peripheral of your preferred microcontroller. This application note explains how to use a microprocessor’s UART to implement a 1-Wire® bus master. It includes an explanation of the required electrical interface, UART configuration, and timing relationship between UART and […]

App note: Implement capacitive sensing on a PIC10F microcontroller

Here’s an app note from Microchip describing how to implement capacitive sensing using two pins on the tiny PIC10F microcontroller. Capacitive sensing is implemented by turning the comparator into a relaxation oscillator. The output of the comparator is used to charge and discharge the sensing capacitor, that is formed by a pad on the circuit […]