描述 Description

The LD3985 provides up to 150 mA, from 2.5 V to 6 V input voltage. The ultra low drop voltage, low quiescent current and low noise make it suitable for low power applications and in battery-powered systems. Regulator ground current increases slightly in dropout only, prolonging the battery life. Power supply rejection is better than 60 dB at low frequencies and rolls off at 10 kHz. High power supply rejection is maintained down to low input voltage levels common to battery operated circuits. Shutdown logic control function is available, this means that when the device is used as local regulator, it is possible to put a part of the board in standby, decreasing the total power consumption. The LD3985 is designed to work with low ESR ceramic capacitors. Typical applications are in mobile phones and similar battery-powered wireless systems.

特性 Features

? Input voltage from 2.5 to 6 V
? Stable with low ESR ceramic capacitors
? Ultra low-dropout voltage (60 mV typ. at 150 mA load, 0.4 mV typ. at1 mA load)
? Very low quiescent current (85 μA typ. at no load, 170 μA typ. at 150 mA load; max.1.5 μA in OFF mode)
? Guaranteed output current up to 150 mA
? Wide range of output voltages: 1.22 V; 1.8 V; 2.5 V; 2.7 V; 2.8 V;2.9 V; 3.3 V; 4.7 V
? Fast turn-on time: typ. 200 μs [CO = 1 μF, CBYP = 10 nF and IO = 1 mA]
? Logic-controlled electronic shutdown
? Internal current and thermal limit
? Output low noise voltage 30 μVRMS over 10 Hz to 100 kHz
? SVR of 60 dB at 1 kHz, 50 dB at 10 kHz
? Temperature range: -40 °C to 125 °C

簡介

LD3985屬于集成電路（IC）的線性+開關穩(wěn)壓器。由制造生產的LD3985穩(wěn)壓器 - 線性線性穩(wěn)壓器用于提供穩(wěn)定的輸出電壓，無論負載電流、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，而且要超出某個最小量，并且在工作時會將輸入端的任何多余電壓轉換為熱量。對于大多數(shù)應用而言，雖然這種穩(wěn)壓器的效率低于開關模式的穩(wěn)壓器，但它們通常更適合對噪聲高度敏感的應用。