Author Archives: DP

App note: The importance of compensation capacitors on the eFuse power line

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Inductive spike on voltage rails causes eFuse to shutdown, here’s an app note from ON Semiconductors on how they solve this problem from happening. Link here (PDF)

ON Semiconductor produces a wide variety of silicon based protection products including current limiting devices such as Electronic Fuses (eFuses). During an over−current stress, eFuses can limit the current applied to a load as well as remove power from the load entirely. This fundamental feature of the eFuse makes it an easy choice to protect against inrush currents which can be seen on power lines of hard−disk drive (HDD) and enterprise−server systems during hot−plug operation or load−fault conditions. During the eFuse current limiting operation, the threat exists of an inductive spike on the power line (VCC) at the point of device turn−off due to thermal shutdown. This Application Note will discuss the failure mechanism this threat exposes the eFuse to, and will explain how to combat it by adding compensation capacitors onto the power line when using the auto−retry (MN2) version of the eFuse.

App note: eFuse reverse voltage protection

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App note from ON Semiconductors about eFuses’ ability to block reverse voltage. Link here (PDF)

One area in which they (eFuses) differ in performance is reverse polarity protection. While a TVS device and polyfuse will protect against reverse voltages, the nature of an integrated semiconductor device does not inherently allow for this type of protection.
This simple circuit allows the device to protect against reverse voltage situations by simply blocking the reverse voltage. This is equivalent of the action of a poly fuse only with less leakage. In comparison to a mechanical fuse, this is a far superior solution since the mechanical fuse will not reset and this circuit will automatically reset when the correct voltage is applied.

App note: Implementation of error code correction in EEPROMs

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App note from ON Semiconductors about their EEPROM error correction. Link here (PDF)

Some of ON’s automotive EEPROMs, like the Grade 0 NV25xxx family (SPI, 1 – 64 Kb) and the Grade 1 CAV24Cxx / CAV25xxx (Grade 1, 128 Kb and higher) implement an Error Code Correction scheme. What this means is that for each chunk of data in the EEPROM array (8 bits for 1 – 64 Kb densities, 32 bits for 128 Kb and higher), the memory stores a redundancy code in separate EEPROM cells.

App note: Revolutionizing analog to digital conversion

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App note from ON Semiconductors introducing their nano power ADC NCD9801x. Link here (PDF)

The NCD9801x ADC is a differential 12−bit resolution successive approximation register analog−to−digital converter unlike any other SAR ADC available on the market. It uses an innovative design to keep a low input capacitance of 2 pF, easily besting the typical SAR ADC input capacitance. The analog power consumption of the NCD9801x converter can reach nano−Watt levels during conversion and can be scaled dynamically based on the clock rate. These two unique traits allow designers to utilize the NCD9801x in design applications that have previously been unachievable.

App note: Applications of current DACs

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App note from Maxim Integrated about current DACs and their uses. Link here

The worldwide use of the electronic devices creates high demands for DACs to connect digital systems to the analog world such as the fiber optical communication networks, to bias photo diodes or to digitally control analog devices such as power supplies to precisely deliver stable, high-resolution currents from the very low microamps to hundreds of milliamps. The output stage of a DAC can be designed to provide a voltage or current output. This application note discusses the current output type and its intended applications.

App note: Design and application guide of bootstrap circuit for high-voltage gate-drive IC

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A deeper dive into controlling gates of MOSFETs with boostrap circuits talked in this app note from ON Semiconductors. Link here (PDF)

The purpose of this paper is to demonstrate a systematic approach to design high−performance bootstrap gate drive circuits for high−frequency, high−power, and high−efficiency switching applications using a power MOSFET and IGBT. It should be of interest to power electronics engineers at all levels of experience. In the most of switching applications, efficiency focuses on switching losses that are mainly dependent on switching speed. Therefore, the switching characteristics are very important in most of the high−power switching applications presented in this paper. One of the most widely used methods to supply power to the high−side gate drive circuitry of the high−voltage gate−drive IC is the bootstrap power supply.