App note: Tire pressure monitor system

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NXP Semiconductor’s implementation of Tire pressure monitor (TPM) system. Link here (PDF)

The Tire Pressure Monitoring System Reference Design consists of five modules: four tire modules and a receiver module. The tire modules consist of the MPXY80xx, the RF2, a battery, several discrete components, and a printed antenna. The receiver module has the MC33954, the KX8, five LEDs to display the status, a battery, a power supply connection, and an RS-232 serial interface.

App note: Crystal oscillator troubleshooting guide

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App note from NXP Semiconductors dealing with oscillators in microcontrollers. Link here (PDF)

Most microcontrollers can use a crystal oscillator as their clock source. Other options include external canned oscillators, resonators, RC oscillators, and internal clocks. The main advantages of a crystal oscillator are frequency accuracy, stability, and low power consumption. However, high reliability is needed to fully benefit from these advantages.

App note: Active cell balancing in battery packs

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Cell balancing implementation from NXP Semiconductors. Link here (PDF)

Batteries made of multiple cells connected in series are often used as a power source for common electronic devices. In multicell battery chains, small differences between the cells (due to production tolerances or operating conditions) tend to be magnified with each charge or discharge cycle. In these situations, weaker cells are overstressed during charging, causing them to become even weaker, until they eventually fail and cause a premature failure of the whole battery. Cell balancing is a way of compensating for these weaker cells by equalizing the charge on all the cells in the chain, thus extending the battery life.

App note: How to measure the power consumption of a peripheral

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Application note from NXP Semiconductors on MCU peripheral power consumption measurement. Link here (PDF)

This Application Note outlines the steps to measure the power consumption of a peripheral and figure out some key points in the measurement. The document takes low-power timer (LPTMR) and LPUART as examples to introduce the method to measure the power consumption of peripheral. The test code is developed in IAR and FRDM-KE15Z board.

App note: TEA1938T GreenChip SMPS control IC

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TEA1938T SMPS control IC application note from NXP Semiconductors. Link here (PDF)

The TEA1938T is a high-featured low-cost DCM and QR mode flyback converter controller. It provides high efficiency at all power levels and very low no-load power consumption at nominal output voltage in burst mode operation.

To minimize ripple, the burst mode uses a small hysteresis scheme. The TEA1938T is designed to support multiple-output-voltage applications like USB PD (Type C) power supplies. Typical applications include notebooks and tablet adapters, fast charging, and direct charging adapters.