App note: Modern thermocouples and a high-resolution DeltaSigma ADC enable high-precision temperature measurement


Old app note from Maxim Integrated about high-precision temperature measurement. Link here (PDF)

Many industrial and medical applications require temperature measurements with accuracies of ±1°C or better, performed with reasonable cost over a wide range of temperatures (-270°C to +1750°C), and often with low power consumption. Properly selected, standardized, modern thermocouples paired with high-resolution ADC data acquisition systems (DASs) can cover this wide temperature range and ensure reproducible measurements, even in the harshest industrial environments.

App note: Sterilization methods and their impact on medical devices containing electronics

App note from Maxim Integrated on electronic devices sterilization. Link here (PDF)

Although there is considerable literature about sterilization methods and equipment, there is very little written about the impact of sterilization on electronics. This article compares popular sterilization methods and discusses their suitability for objects containing electronics.

App note: Map colors of a CIE plot and color temperature using an RGB color sensor


An app note from MAXIM integrated on RGB color sensor and their capability to correct color deviation by providing feedback based on a reference color. Link here (PDF)

This application note will show how all the colors within the color gamut formed by red, green, and blue constants in a CIE plot can be measured and mapped with an RGB color sensor. This RGB sensor can also monitor the color output of LEDs in a display and/or provide feedback to maintain a reference color. An RGB sensor will also be mapped to measure the color temperature of practical light sources.

App note: Fundamentals of operation and recent developments of class D amplifiers


Good read about class D amplfiers from MAXIM Integrated. Link here (PDF)

A Class D amplifier’s high efficiency makes it ideal for portable and compact high-power applications. Traditional Class D amplifiers require an external lowpass filter to extract the audio signal from the pulse-width-modulated (PWM) output waveform. Many modern Class D amplifiers, however, utilize advanced modulation techniques that, in various applications, both eliminate the need for external filtering and reduce electromagnetic interference (EMI). Eliminating external filters not only reduces board-space requirements, but can also significantly reduce the cost of many portable/compact systems.

App note: Avoid overvoltage stresses by minimizing power supply pumping on single-ended output, class D audio amplifiers


Here’s class D audio amplifier pumping remedy from MAXIM Integrated, power-supply pumping is a problem that occurs when playing low-frequency audio signals through a single-ended output. Link here (PDF)

This application note explains what power-supply pumping is and how it occurs in designs that employ a Class D audio amplifier with single-ended output loads. The article presents three design solutions that will reduce the problem. Mathematical equations show that use of power-supply capacitors greater than 1000µF greatly reduce the phenomenon.

App note: High-frequency automotive power supplies


Switching power supply used in automotive electronics app note from Maxim Integrated. Link here (PDF)

The combination of high switching frequency and high-voltage capability is difficult to achieve in IC design. You can, however, design an automotive power supply that operates with high frequency if you protect it from temporary high-voltage conditions. High-frequency operation is becoming important as more and more electronic functions are integrated into the modern automobile. This article discusses several ways to protect low-voltage electronic circuits from the harsh effects of the automotive electrical environment. Also included are the results of laboratory tests for noise immunity.

App note: Fan speed control is cool!


App note from Maxim Integrated about their MAX6650 and MAX6651 fan controllers chip. Link here (PDF)

Temperature-based fan control is a necessity in a growing number of systems, both to reduce system noise and to improve fan reliability. When fan control is augmented by fan-speed monitoring, a speed-control loop can be implemented that is independent of manufacturing variances and wear on the fan. In addition, a fan that is about to fail can be identified so that it can be replaced before it fails.

App note: Choose the right power supply for your FPGA


Designing a power supply for FPGA includes multiple voltage, ripple management and power sequencing, here’s an app note from Maxim Integrated. Link here (PDF)

Field-programmable gate arrays (FPGAs) and complex programmable logic devices (CPLDs) require 3 to 15, or even more, voltage rails. The logic fabric is usually at the latest process technology node that determines the core supply voltage. Configuration, housekeeping circuitry, various I/Os, serializer/deserializer (SerDes) transceivers, clock managers, and other functions all have differing requirements for voltage rails, sequencing/tracking, and voltage ripple limits. An engineer must consider all of these issues when designing a power supply for an FPGA.

App note: Current-sense amplifier doubles as a high common mode instrumentation amplifier


Application note from Maxim intergrated on utilizing a boost converter and a current-sense amplifier to form a regulator that derives +5V from -48V without isolation. Link here (PDF)

Instrumentation amplifiers (IAs) are used where gain accuracy and dc precision are important, such as in measurement and test equipment. The downside of IAs is the cost. However, inexpensive current-sense amplifiers handle high common-mode voltages and share some traits with IAs. As a result, in some applications, such as a ground-referenced -48V to +5V power converter, current-sense amplifiers can replace IAs, thereby reducing cost.

App note: Microcontroller Clock – crystal, resonator, RC Oscillator, or silicon oscillator?


App note from Maxim Integrated on clock sources of microcontrollers and their strengths and weaknesses. Link here

The majority of clock sources for microcontrollers can be grouped into two types: those based on mechanical resonant devices, such as crystals and ceramic resonators, and those based on electrical phase-shift circuits such as RC (resistor, capacitor) oscillators. Silicon oscillators are typically a fully integrated version of the RC oscillator with the added benefits of current sources, matched resistors and capacitors, and temperature-compensation circuits for increased stability.