App note: High-power emitters for illumination applications

App note from OSRAM on High-power LEDs and their special requirements. Link here (PDF) In general high power emitters can be driven with DC currents in the range of 1 Ampere whereas most low power products like 5 mm Radials are limited to 100 mA. As the light output increases with driving current the optical […]

App note: MC13783 buck and boost inductor sizing

NXP’s app note on calculating inductor sizes using MC13783 PWM controller as example. Link here (PDF) The purpose of this application note is to provide a method of choosing the size of the inductors for the optimized switching regulators versus the current consumption of the application. This will allow to optimize the size and the […]

App note: Analog switch lowers relay power consumption

Clever way of starting-up relays discussed in this app note from Maxim Integrated. Link here Relays are often used as electrically controlled switches. Unlike transistors, their switch contacts are electrically isolated from the control input. On the other hand, the power dissipation in a relay coil may be unattractive for battery-operated applications. You can lower […]

App note: Ferrite bead demystified

App note from Analog Devices hinting for proper selection of ferrite bead for you applications. Link here (PDF) An effective method for filtering high frequency power supply noise and cleanly sharing similar supply rails is the use of ferrite beads. A ferrite bead is a passive device that filters high frequency noise energy over a […]

App note: Silicon Labs’ TS3004 VS. the CMOS 555 – Determining lowest supply current for battery-powered applications

Good read on this app note from Silicon Labs comparing their low power but obsolete timer. Link here (PDF) The 555 timer is the workhorse of ICs, with close to a billion of them manufactured every year. Introduced in 1972, the 555 is still in widespread use because of its ease of use, reasonable price, […]

App note: Single-cell regulated Q-pump draws low quiescent current

Q-pump an alternative to inductor charge pump boost regulator for low power and sleepy microcontroller from Silicon Labs. Link here (PDF) In the switch-mode power supply world, capacitor-based charge pumps (or Q-pumps) generally aren’t useful for heavy lifting, but work well in niche micropower applications where space is at a premium. They work best in […]

App note: Core independent voltage window signal detection using a single comparator

Presenting the usage of Core independent paripheral of PICs in this app note from Microchip. Link here (PDF) It is possible to find out whether a measured signal is below or above a certain value/reference using a single comparator. But, what if the desired interval is between two values, the undervoltage and overvoltage protection? The […]

App note: Power supply rejection ratio of low dropout voltage regulators

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, […]

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 […]