LM3670MF-1.5/NOPB屬于集成電路（IC）的穩(wěn)壓器-DC-DC開(kāi)關(guān)穩(wěn)壓器。由美國(guó)德州儀器公司制造生產(chǎn)的LM3670MF-1.5/NOPB穩(wěn)壓器 - DC-DC 開(kāi)關(guān)穩(wěn)壓器DC-DC 開(kāi)關(guān)穩(wěn)壓器 PMIC（電源管理集成電路）產(chǎn)品族中的產(chǎn)品是元器件級(jí)設(shè)備，用于需要穩(wěn)定 DC 輸入電壓和/或?qū)⑵滢D(zhuǎn)換為不同幅度的輸出電壓的應(yīng)用。這些器件與稱為“控制器”P(pán)MIC 的類似產(chǎn)品的區(qū)別在于集成了主開(kāi)關(guān)元件，設(shè)備提供的電力會(huì)通過(guò)該元件。

1 Features

1? Input Voltage Range: 2.5 V to 5.5 V

? Adjustable Output Voltages (VOUT): 0.7 V to 2.5 V

? Fixed Output Voltages: 1.2 V, 1.5 V, 1.6 V, 1.8 V,

1.875 V, 3.3V

? 15-μA Typical Quiescent Current

? 350-mA Maximum Load Capability

? 1-MHz PWM Fixed Switching Frequency (Typical)

? Automatic PFM and PWM Mode Switching

? Low Dropout Operation – 100% Duty Cycle Mode

? Internal Synchronous Rectification for High

Efficiency

? Internal Soft Start

? 0.1-μA Typical Shutdown Current

? Current Overload Protection

? Operates from a Single Li-Ion Cell or Three-Cell

NiMH/NiCd Batteries

? Only Three Tiny Surface-Mount External

Components Required (One Inductor, Two

Ceramic Capacitors)

2 Applications

? Mobile Phones and Handheld Devices

? PDAs

? Palm-Top PCs

? Portable Instruments

? Battery-Powered Devices

3 Description

The LM3670 step-down DC-DC converter is

optimized for powering ultralow voltage circuits from a

single Li-Ion cell or three-cell NiMH/NiCd batteries. It

provides up to 350-mA load current, over an input

voltage range from 2.5 V to 5.5 V. There are several

different fixed voltage output options available as well

as an adjustable output voltage version.

The device offers superior features and performance

for mobile phones and similar portable applications

with complex power management systems. Automatic

intelligent switching between pulse width modulation

(PWM) low-noise and pulse frequency modulation

(PFM) low-current mode offers improved system

control. During full-power operation, a fixed-frequency

1-MHz (typical) PWM mode drives loads from

approximately 70 mA to 350 mA maximum, with up to

95% efficiency. Hysteretic PFM mode extends the

battery life through reduction of the quiescent current

to 15 μA (typical) during light current loads and

system standby. Internal synchronous rectification

provides high efficiency (90% to 95% typical at loads

between 1 mA and 100 mA). In shutdown mode

(enable (EN) pin pulled low) the device turns off and

reduces battery consumption to 0.1 μA (typical).

The LM3670 is available in a 5-pin SOT-23 package.

A high switching frequency (1 MHz typical) allows use

of tiny surface-mount components. Only three

external surface-mount components, an inductor and

two ceramic capacitors, are required.