Linear公司的LT8582是帶故障保護的雙路獨立的PWM DC/DC轉(zhuǎn)換器,每路包括42V主開關(guān)和42V從開關(guān),并聯(lián)使用的總電流為3A,具有過壓,超溫以及輸出短路保護.工作電壓2.5V-22V,開關(guān)頻率高達2.5MHz,每路可容易配置成升壓,SEPIC,反向或反激轉(zhuǎn)換器,主要用在本地電源,VFD偏壓電源,TFT-LCD偏壓電源和汽車引擎控制單元(ECU)電源.本文介紹了LT8582主要特性,方框圖,基本應(yīng)用電路以及多種典型應(yīng)用電路與兩種拓撲的元件布局圖.
The LT8582 is a dual independent channel PWM DC/DC converter with a power good pin and built-in fault protection to help guard against input overvoltage and overtemperature
conditions. Each channel consists of a 42V master switch and a 42V slave switch that can be tied together for a total current limit of 3A.
The LT8582 is ideal for many local power supply designs. Each channel can be easily configured in boost, SEPIC, inverting, or flyback configurations. Together, the two channels can produce a 12V and a –12V output with 14.4W of combined output power from a 5V input. In addition, the LT8582’s slave switch allows the part to be configured in
high voltage, high power charge pump topologies that are more efficient and require fewer components than traditional circuits.
The LT8582 also features innovative SHDN pin circuitry that allows for slowly varying input signals and an adjustable undervoltage lockout function. Additional features such as
output short protection, frequency foldback and soft-start are integrated. The LT8582 is available in a 24-pin 7mmx 4mm DFN package.
LT8582主要特性:
Dual 42V, 3A Combined Power Switch
Master/Slave (1.7A/1.3A) Switch Design
Wide Input Range: 2.5V to 22V Operating, 40V Maximum Transient
Power Good Pin for Event Based Sequencing
Switching Frequency Up to 2.5MHz
Each Channel Easily Configurable as a Boost, SEPIC, Inverting or Flyback Converter
Low VCESAT Switch: 270mV at 2.75A (Typical)
Can be Synchronized to an External Clock
Output Short-Circuit Protection
High Gain SHDN Pin Accepts Slowly Varying Input Signals
24-Pin 7mmx 4mm DFN Package
LT8582應(yīng)用:
Local Power Supply
Vacuum Fluorescent Display (VFD) Bias Supplies
TFT-LCD Bias Supplies
Automotive Engine Control Unit (ECU) Power
圖1. LT8582方框圖
圖2. LT8582升壓轉(zhuǎn)換器電路圖:1.5MHz,5V到12V升壓
圖3. LT8582 SEPIC轉(zhuǎn)換器電路圖:700kHz,3V-19V到5V SEPIC拓撲
圖4. LT8582雙電感反向轉(zhuǎn)換器電路圖:1.5MHz,5V到-12V反向電壓
圖5. LT8582高VOUT電荷泵拓撲電路圖
圖6. LT8582 5V到+/-12V升壓和反向電壓電路圖
圖7. LT8582 VFD和燈絲電源電路圖:1MHz開關(guān)頻率
圖8. LT8582 2.7V-5.5V輸入+/-15V輸出電路圖
圖9. LT8582超大電容備份電源電路圖
圖10. LT8582 3-19V輸入12V和15V順序輸出電路圖
圖11. LT8582升壓和雙電感反向電源拓撲元件布局圖
圖12. LT8582 SEPIC和雙電感反向電源拓撲元件布局圖
詳情請見:
http://cds.linear.com/docs/Datasheet/8582f.pdf
