L4979MD屬于集成電路（IC）的線(xiàn)性+開(kāi)關(guān)穩(wěn)壓器。由意法半導(dǎo)體集團(tuán)制造生產(chǎn)的L4979MD穩(wěn)壓器 - 線(xiàn)性線(xiàn)性穩(wěn)壓器用于提供穩(wěn)定的輸出電壓，無(wú)論負(fù)載電流、輸入電壓或環(huán)境因素如何變化，這些輸出電壓通常都要保持不變。它們的工作原理要求輸入電壓維持在高于所需的輸出電壓，而且要超出某個(gè)最小量，并且在工作時(shí)會(huì)將輸入端的任何多余電壓轉(zhuǎn)換為熱量。對(duì)于大多數(shù)應(yīng)用而言，雖然這種穩(wěn)壓器的效率低于開(kāi)關(guān)模式的穩(wěn)壓器，但它們通常更適合對(duì)噪聲高度敏感的應(yīng)用。

描述 Description

L4979D and L4979MD are low dropout linear regulators with microprocessor control functions such as low voltage reset, watchdog, on/off control. Typical quiescent current is 100 μA in very low output current mode and enabled regulator. The devices drop to 6 μA with not enabled regulators.

On chip trimming results in high output voltage accuracy (2). Accuracy is kept over wide temperature range, line and load variation.

The maximum input voltage is 40 V. The max output current is internally limited. Internal temperature protection disables the voltage regulator output.

特性 Features

■ Operating DC supply voltage range 5.6 V to 31 V

■ Low quiescent current (6 μA typ. @ 25 °C with enable low)

■ High precision output voltage (2)

■ Low dropout voltage less than 0.5 V

■ Reset circuit sensing the output voltage down to 1 V

■ Programmable reset pulse delay with external capacitor

■ Watchdog

■ Programmable watchdog timer with external capacitor

■ Thermal shutdown and short circuit protection

■ Automotive temperature range (Tj = -40 °C to 150 °C)

■ Enable input for enabling/disabling the voltage regulator output