OnSemiLV5980MC低功率損耗、高效轉(zhuǎn)換降壓型穩(wěn)壓器設(shè)計(jì)方案

OnSemi公司的LV5980MC是一款內(nèi)嵌P溝道MOSFET的單通道DC-DC轉(zhuǎn)換器，工作電壓范圍為4.5V至23V，最大輸出電流為3A。可實(shí)現(xiàn)低功率損耗，操作電流大約為63uA。該芯片具有外部電容軟啟動(dòng)、過(guò)流保護(hù)、欠壓及過(guò)熱關(guān)閉等功能特性。本文首先介紹LV5980MC、基本特性、內(nèi)部框圖及應(yīng)用領(lǐng)域，并給出相應(yīng)設(shè)計(jì)方案的設(shè)計(jì)原理圖、元器件列表及PCB元件布局圖。

LV5980MC is 1ch DC-DC converter with built-in power Pch MOSFET.The recommended operating rang is 4.5V to 23V.The maximum current is 3A.The operating current is about 63uA,and low power consumption is achieved.

LV5980MC主要特性：

·1ch SBD rectification DC-DC converter IC with built-in power Pch MOSFET
·Typical value of light load mode current is 63uA
·100mΩ High-side switch
·The oscillatory frequency is 370kHz
·When P-by-P is generated continuously,it shifts to the HICCUP opration
·External capacitor Soft-start
·4.5V to 23V Operating input voltage range
·Output voltage adjustable to 1.235V
·built-in OCP circuit with P-by-P method
·Under voltage lock-out,thermal shutdown

LV5980MC應(yīng)用：

·Set top boxes
·point of load DC-DC converters
·White Goods
·DVD/Blu-ray? drivers and HDD
·Office Equipment
·LCD monitors and TVs
·POS System


圖1. LV5980MC內(nèi)部方框圖

LV5980MC方案介紹：

The LV5980MC is a fixed 370 KHz, high-output-current, Non-synchronous PWM converter that integrates a low-resistance, high-side MOSFET and a Customer Chosen, External Diode for the rectification. The LV5980MC utilizes externally compensated current mode control to provide good transient response, ease of implementation, and excellent loop stability. It regulates input voltages from 4.5 V to 23 V down to an output voltage as low as 1.235 V and is able to supply up to 3.0 A of load current. The LV5980MC includes Power Save Feature to enhance efficiency during Light Load. In low consumption mode, the device show operating current of 63 uA from VIN by shutting down unnecessary circuits.

LV5980MC方案主要參數(shù)表



LV5980MC方案原理圖：



圖2. LV5980MC方案原理圖

LV5980MC方案材料清單：



PCB元件布局圖：