Here’s an app note about PSRR of LDO from Microchip. Link here (PDF) The Power Supply Rejection Ratio is the ability of a device, such as a Low Dropout Voltage regulator, to reject the various perturbations that can be found in its input supply rail by providing a greatly attenuated signal at the output. Generally, […]
Category Archives: app notes
App note: Comparison of LED circuits
Another application note from OSRAM on different LED circuit design failure mode. Link here (PDF) In recent years, Light Emitting Diodes (LEDs) have become a viable alternative to conventional light sources. The overriding advantages long life, high efficiency, small size and short reaction time have lead to the displacement, in ever increasing numbers, of incandescent […]
App note: Dimming LEDs with respect to grouping current
App note from OSRAM describing the behaviour of LEDs in respect to brightness by varying the current and to suggest solutions for avoiding negative influence for the application. Link here (PDF) In the design of a driving circuit for LEDs, the dimming behaviour is an important topic to fulfill the end customer requirements. The behaviour […]
App note: Passive entry door system with proximity sensor
A full implementation of a keyless entry from Microchip. Link here (PDF) The door access systems have evolved from simple physical keys to more sophisticated keyless entry systems. Now, we have a system that automatically unlocks the door when user carrying an access key approaches the door handle. As it does not require any user […]
App note: Low Power POE Flyback Converter
App note from Microchip about their MIC2145 boost switching regulator to do POE Flayback conversion. Link here (PDF) The MIC2145 skip mode controller is used to implement a flyback converter that is intended for use in nonisolated, low power, POE applications. The circuit has a nominal 48V input and supports the POE voltage range of […]
App note: Consideration of self pollution reduction for electronic systems
App note from ON Semiconductors on EMI self pollution. Link here (PDF) This application note will address the problem of Electro Magnetic Interference (EMI) self pollution in which one part of an electrical systems such as cell phones and consumer electrical products emit radiation that interferes with the operation of other parts of the system.
App note: 1 kV SenseFET integrated power switch
App note from ON Semiconductors on their FSL4110LR power switch for SMPS power supplies. Link here (PDF) Some industrial equipment that are supplied from a threephase AC power source such as industrial drives and energy meters often need an auxiliary power supply stage that can provide a regulated low-power DC source for analog and digital […]
App note: Programmable analog functions
Another app note from ON Semiconductors about various digital potentiometers application. Link here (PDF) Analog circuits are made programmable by using digital potentiometers (POTs) to vary the key circuit parameters. This application note provides the analog design engineer with basic reference designs and circuit ideas for controlling the key parameters of analog circuits using digital […]
App note: Digital potentiometer (POT) to control LED brightness
Controlling LED brightness through digital potentiometer and a LED driver from ON Semiconductor. Link here (PDF) Light-emitting diodes (LEDs) require a regulated current, and their brightness is proportional to the current that flows through them. Some LED drivers use an external resistor to set the LED current. A digital POT can replace a discrete resistor […]
App note: High density serial flash addressing
Old app note from Macronix about accessing high density serial flash. Link here (PDF) Many consumer products have converted or are converting from parallel flash to SPI serial flash. Generally, high end applications require higher memory density, but in the past, serial flash densities were limited to 128Mb due to addressing constraints.
App note: USB On-The-Go (OTG) basics
USB OTG explained in this app note from Cypress Semiconductors. Link here This application note discusses several aspects of OTG functionality. The note introduces end-applications and different types of cables and connectors involved with OTG. It also describes the OTG protocol state changes when both Mini-A and Mini-B devices are connected .The host negotiation protocol […]
App note: Meeting transient specifications for electrical systems in military vehicles
Hardened circuit protection against voltage spikes and surges tackled in this app note from Vicor. Link here (PDF) Electrical systems in military vehicles are normally required to meet stringent transient requirements. Typical of these specifications is the MIL-STD-1275B. Although the specified levels of these surges and spikes are outside the capability of Vicors Maxi, Mini, […]
App note: Intelligent lighting controller measures ambient light and tracks time
Implementation on ambient light and time tracking luminaires controller from MAXIM Integrated, Link here This reference design explains how to design an intelligent lighting controller that senses and measures the ambient light level with an ambient light sensor (ALS). Equipped with a real-time clock (RTC), the controller also knows when to turn lighting on or […]
App note: Selecting the right CMOS analog switch
App note from MAXIM Integrated digging on the basics of CMOS analog switches and the latest improvement on them from the standard one. Link here Integrated analog switches often form the interface between analog signals and a digital controller. With the large number of analog switches on the market today, there are many performance criteria […]
App note: Gate-source voltage behaviour in a bridge configuration
App note from ROHM semiconductor on MOSFETS and IGBTs. Link here (PDF) Power switching devices such as MOSFETs and IGBTs are used for various kinds of power supply applications, power supply line switching components, and other power applications. In addition, the circuit topologies used are diverse, parallel and series connections are widely used, not to […]
App note: Board level application notes for DFN and QFN packages
Board mounting an DFN/QFN (Dual/Quad Flat-Pack No lead) application note from ON Semiconductor. Link here (PDF) The DFN/QFN platform offers a versatility which allows either a single or multiple semiconductor devices to be connected together within a leadless package. These guidelines include printed circuit board mounting pads, solder mask and stencil pattern and assembly process […]
App note: Why honest weigh scales are application specific
App note from Maxim Integrated discussing strain gauge and accompanying circuit are used in today’s weight measurement applications. Link here (PDF) Current laws and regulations require honesty, tolerance, and accuracy in weigh scales. The most commonly used weight-measurement element is the strain gauge. This application note explains how strain gauges are useful in multiple applications […]
App note: How to shrink your USB Type-C battery charger
Maxim’s app note on a highly compact Type-C charger solution. Link here (PDF) A highly integrated solution, as seen with the MAX77860 USB Type-C 3A switch-mode charger, dramatically reduces system complexity by integrating the charger, the power path, the Safeout LDO, ADC, and the USB-C CC and BC 1.2 detection in a small 3.9mm x […]
App note: Overture series high power solutions
This application note (PDF) from TI discusses the different aspects of the Overture series high-power solutions, and discusses three application circuits: parallel, bridged, and bridged/parallel configurations The objective is to provide simple high-power solutions that are conservatively designed, highly reliable and have low part count. This document provides three specific, but not unique, application circuits […]
App note: Magnetometer placement in mobile devices
App note from Kionix about magnetometer integration challenges from the mobile equipment point of view, and gives guidelines for the mounting position of the magnetic sensor. Link here (PDF) Electronic devices contain many parts which can affect a magnetic sensor. When deciding the mounting position, it is necessary to consider the types of materials and […]