</a>DC/DC转换器" title="DC/DC转换器">DC/DC转换器" title="DC/DC转换器">DC/DC转换器,集成了开关控制器,功率FET,电感和所有支持元件.输入电压4.5V-16V,输出电压0.6V-2.5V,多个应用时输出电流高达100A,可调开关频率,频率同步,过流保护,内部温度检测二极管输出,输出过压保护,主要用在通信和网络设备,存储器和ATCA卡,工业设备.本文介绍了LTM4620主要特性,简化框图和多种应用电路,00A多相演示板1780A-C主要特性,电路图,材料清单和PCB元件布局图.

The LTM®4620 is a complete dual 13A output switching mode DC/DC power supply. Included in the package are the switching controller, power FETs, inductors, and all supporting components. Operating from an input voltage range of 4.5V to 16V, the LTM4620 supports two outputs each with an output voltage range of 0.6V to 2.5V, set by a single external resistor. Its high efficiency design delivers up to 13A continuous current for each output. Only a few input and output capacitors are needed.

The device supports frequency synchronization, multiphase operation, Burst Mode operation and output voltage tracking for supply rail sequencing and has an onboard temperature diode for device temperature monitoring. High switching frequency and a current mode architecture enable a very fast transient response to line and load changes without sacrificing stability.

Fault protection features include overvoltage and overcurrent protection. The power module is offered in a proprietary space saving and thermally enhanced 15mm × 15mm ×4.41mm LGA package with integrated top-side heat sink.

The LTM4620 is RoHS compliant with a PB-free finish.

LTM4620主要特性:

Complete Standalone Dual Output Power Supply

Dual 13A or Single 26A Output

Wide Input Voltage Range: 4.5V to 16V

Output Voltage Range: 0.6V to 2.5V

±1.5% Maximum Total DC Output Error

Multiphase Current Sharing with Multiple LTM4620s Up to 100A

Differential Remote Sense Amplifier

Current Mode Control/Fast Transient Response

Adjustable Switching Frequency

Overcurrent Foldback Protection

Frequency Synchronization

Internal Temperature Sensing Diode Output

Output Overvoltage Protection

Low Profile (15mm × 15mm × 4.41mm) LGA Package

TM4620应用:

Telecom and Networking Equipment

Storage and ATCA Cards

Industrial Equipment

图1.LTM4620简化框图

图2.输出跟踪的LTM4620应用电路

图3.LTM4620 5V-16V输入,1.5V和1.2V 13A输出电路图

图4.LTM4620带温度监视的2相1.5V 26A应用电路

图5.LTM4620 1.2V和1V 输出跟踪电路

图6.LTM4620 4相1.2V 50A电路图

演示板1780A-C

Demonstration circuit 1780A-C features poly phase design using the LTMR4620EV, the high efficiency, high density, dual 13A, switch mode step-down power module regulator.

The input voltage is from 4.5V to 16V. The output voltage is jumper selectable from 1.0V to 2.5V. DC1780A-C can deliver nominal 100A output current with 4× LTM4620s in parallel. As explained in the data sheet, output current derating is necessary for certain VIN, VOUT, and thermal conditions. The LTM4620 on DC1780A-C always operates in continuous conduction mode. The switching frequency can be programmed through a resistor or can be synchronized to an external clock signal. The board allows the user to program how its output voltage ramps up and down through the TRACK_CONTROL pin. The output voltage is tightly regulated between VOUT + and VOUT – through remote output voltage sensing which improves output voltage regulation at heavy loads. These features and the availability of the LTM4620EV in a compact 15mm × 15mm × 4.41mm LGA package make it ideal for use in many high density point-of-load regulation applications.

The LTM4620 data sheet must be read in conjunction with this demo manual prior to working on or modifying the demo circuit DC1780A-C.

图7.100A多相演示板1780A-C外形图

图8.100A多相演示板1780A-C电路图(1)

图9.100A多相演示板1780A-C电路图(2)

图10.100A多相演示板1780A-C电路图(3)

图11.100A多相演示板1780A-C电路图(4)

100A多相演示板1780A-C材料清单(BOM):



图12.100A多相演示板1780A-C PCB元件布局图(顶层)

图13.100A多相演示板1780A-C PCB元件布局图(底层)
详情请见:
http://cds.linear.com/docs/Datasheet/4620f.pdf
和
http://cds.linear.com/docs/Demo%20Board%20Manual/dc1780acfa.pdf
以及
http://cds.linear.com/docs/Demo%20Board%20Schematic/1780a-csch.pdf