App note: Quad-SPI (QSPI) interface on STM32 microcontrollers

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Extend memories by using external high speed memories interfaced to Quad-SPI modules on STM32 micros, app note from STMicroelectronics. Link here (PDF)

This application note describes the Quad-SPI interface on the STM32 microcontrollers and explains how to use the module to configure, program, and read external Quad-SPI memories. It describes some typical use cases to use Quad-SPI interface based on some software examples from the STM32Cube firmware package and from the STM32F7 application notes.

App note: How to avoid chipLEDs sticking to cover tape during automated tape-and-reel assembly

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Investigative app note from Vishay on preventing too light components from sticking on the cover tape of their reel. Link here (PDF)

Customers have informed Vishay that 0603 LEDs (ChipLEDs) supplied in tape and reel format sometimes stick to the PSA cover tape that is peeled off from the carrier tape during the assembly process. This application note describes the problem and provides a summary of precautions that can be used to prevent this unwanted effect from happening.

App note: A simple alternative to analog isolation amplifiers

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A linear isolation amplifier from Silicon Labs app note. Link here (PDF)

Analog circuits sometimes require linear (analog) signal isolation for safety, signal level shifting, and/or ground loop elimination. Linear signal isolation is typically difficult to implement, costly, and often exhibits mediocre performance. While the design community thirsts for a flexible and inexpensive linear isolator solution, it is the analog isolation amplifier (ISOamp) that most often captures the socket.

App note: Ambient light sensor SFH5701

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App note from OSRAM on their ALS device SFH5701, its operation and application method. Link here (PDF)

The SFH5701 is a small, two-wire, linear output current ambient light sensor (ALS) with current amplifier and dark current compensation. The ALS is capable of resolving a wide range of ambient light levels (10 mlx – 10 klx) tailored to the spectral response of the human eye and operational from -40 °C to 100 °C.

App note: How to achieve greater accuracy in battery capacity readings for portable designs

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App note from Maxim Integrated on using fuel gauge IC to obtain accurate battery state of charge readings. Link here (PDF)

Because a product’s runtime is limited by battery capacity, it’s critical to have a precise method for measuring the remaining battery capacity to avoid an unexpected shutdown. This application note describes an experiment for obtaining accurate battery capacity readings in a dog-tracking project.

App note: Single-Channel power supply monitor with remote temperature sense

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App note from Linear Technology using their LTC2970 to monitor external temperature aside from doing power management. Link here (PDF)

Many applications with a single power regulator can benefit from the monitoring and control features of a power supply manager, but most power supply manager ICs have more than one channel. In an application that only has one power supply, there will be an unused set of DAC and ADC pins. Instead of letting the unused channel go to waste, we can use these pins, and a bit of microcontroller code, to sense remote temperature.

App note: AMR angle sensors

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Position measurement sensor using magnetoresistive technology discussed in this app note from Analog Devices. Link here (PDF)

Anisotropic magnetoresistive (AMR), thin film materials are becoming increasingly important in today’s position sensing technologies. Magnetoresistive (MR) position measurement has many advantages over traditional technologies. Reliability, accuracy, and overall robustness are the primary factors contributing to the development of MR sensing technologies. Low cost, small relative size, contactless operation, wide temperature range, dust and light insensitivity, and operation over a wide magnetic field range all lead to a robust sensor design.

App note: Overcurrent event detection circuit

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Sample overcurrent detection circuit from Texas Instruments. Link here (PDF)

This is a unidirectional current sensing solution generally referred to as overcurrent protection (OCP) that can provide an overcurrent alert signal to shut off a system for a threshold current and re-engage the system once the output drops below a desired voltage lower than the overcurrent output threshold voltage.