原标题：Linear LTC3897PolyPhase同步升压转换器解决方案

　　Linear公司的LTC3897是带输入/输出保护的PolyPhase™同步升压转换器,能驱动两个N沟功率MOSFET级,输入电压4.5V-65V(高达75V浪涌),输出高达65V,主要用在工业,汽车和军事/航空航天.本文介绍了LTC3897主要特性,框图和十多种应用电路,以及演示板DC2108主要特性,电路图和材料清单.

　　The LTC.3897 is a synchronous boost DC/DC controller with surge stopper and ideal diode controller. The boost controller drives two N-channel power MOSFET stages out-of-phase to reduce input and output capacitor requirements, allowing the use of smaller inductors than the single-phase equivalent. Synchronous rectification reduces power loss and eases thermal requirements.

　　The surge stopper controls the gate of an external N-channel MOSFET to protect against high voltage input transients and provides in-rush current control, overcurrent protection and output disconnect for the boost converter. The integrated ideal diode controller drives another N-channel MOSFET to replace a Schottky diode for reverse input protection and

　　voltage holdup or peak detection. It controls the forward voltage drop across the MOSFET and minimizes reverse current flow.

　　The LTC3897 is available in thermally-enhanced 38-pin leadless QFN or 38-lead TSSOP packages.

　　LTC3897主要特性:

　　nn Input Supply Range: 4.5V to 65V (Up to 75V Surge)

　　nn Reverse Input Protection to –40V

　　nn In-Rush Current Control, Overcurrent Protection and Output Disconnect for Boost Converter

　　nn Input Voltage Surge Protection with Adjustable Clamp Voltage

　　nn Onboard Ideal Diode Controller

　　nn Low Quiescent Current: 55μA

　　nn 2-Phase Operation Reduces Required Input and Output Capacitance and Noise

　　nn Output Voltage Up to 60V

　　nn Adjustable Gate Drive Level 5V to 10V (OPTI-DRIVE) for Logic-Level or Standard Threshold FETs

　　nn No External Bootstrap Diodes Required

　　LTC3897应用:

　　nn Industrial

　　nn Automotive

　　nn Military/Avionics

　　图1. LTC3897框图

　　图2. LTC3897应用电路图(1):24V/10A 2相同步升压转换器

　　图3. LTC3897应用电路图(2):3相工作

　　图4. LTC3897应用电路图(3):4相工作

　　图5. LTC3897应用电路图(4):6相工作

　　图6. LTC3897应用电路图(5):12相工作

　　图7. LTC3897应用电路图(6):高效2相48V升压转换器(1)

　　图8. LTC3897应用电路图(7):高效2相48V升压转换器(2)

　　图9. LTC3897应用电路图(8):高效2相24V升压转换器

　　图10. LTC3897应用电路图(9):高效2相48V升压转换器(3)

　　图11. LTC3897应用电路图(10):高效2相48V升压转换器(4)

　　图12. LTC3897应用电路图(11):高效2相48V升压转换器(5)

　　图13. LTC3897应用电路图(12):非同步107V/1.5A 2相48V升压转换器

　　演示板DC2108

　　Demonstration circuit DC2108 is DC/DC boost converter featuring the LTCR3897 constant frequency current mode boost controller. The DC2108A operates over a 16V to

　　55V input and provides 4A to 12A of output current. The 160kHz (2 •160kHz at the output) constant frequency operation results in a small and efficient circuit. The converter provides high output voltage accuracy (typically ±3%) over a wide load range with no minimum load requirement. The demonstration circuit can be easily modified to generate different output voltages.

　　The DC2108 has small circuit footprint. It is a high performance and cost effective solution for Telecom, Automotive and Power Over Ethernet applications.

　　演示板DC2108材料清单: