TI TPS54620 6A同步降压稳压方案

TI 公司的TPS54620输入17V输出 6A的同步降压稳压器,集成了26mΩ/ 19mΩ的MOSFET,开关频率从200kHz 到1.6MHz,基准电压为0.8V ±1%,关断静态电流2uA,工作结温-40度到150度C,主要用于高密度分布电源系统,高性能点负载稳压,以及宽带,网络和光纤通信设备.本文介绍了TPS54620的主要特性,方框图, 典型应用电路图, 快速瞬变的3.3V 输出电源(PMP4854-2)电路图以及TPS54620评估板TPS54620EVM-374性能指标和详细电路图和材料清单(BOM).

The TPS54620 in thermally enhanced 3.5mm x 3.5mm QFN package is a full featured 17V, 6A synchronous step down converter which is optimized for small designs through high efficiency and integrating the high-side and low-side MOSFETs. Further space savings are achieved through current mode control, which reduces component count, and by selecting a high switching frequency, reducing the inductors footprint.

The output voltage startup ramp is controlled by the SS/TR pin which allows operation as either a stand alone power supply or in tracking situations. Power sequencing is also possible by correctly configuring the enable and the open drain power good pins.

Cycle by cycle current limiting on the high-side fet protects the device in overload situations and is enhanced by a low-side sourcing current limit which prevents current runaway. There is also a low-side sinking current limit which turns off the low-side MOSFET to prevent excessive reverse current. Thermal shutdown disables the part when die temperature rises too high.

TPS54620主要特性:

Integrated 26mΩ / 19mΩ MOSFETs

Split Power Rail: 1.6V to 17V on PVIN

200kHz to 1.6MHz Switching Frequency

Synchronizes to External Clock

0.8V ±1% Voltage Reference Over Temperature

Low 2uA Shutdown Quiscent Current

Monotonic Start-Up into Prebiased Outputs

-40℃ to 150℃ Operating Junction Temperature Range

Adjustable Slow Start/Power Sequencing

Power Good Output Monitor for Undervoltage& Overvoltage

Adjustable Input Undervoltage Lockout

Supported by SwitcherPro Software Tool

TPS54620应用:

High Density Distributed Power Systems

High Peformance Point of Load Regulation

Broadband, Networking and Optical Communications Infrastructure



图1.TPS54620功能方框图



图2.TPS54620简化电路图



图3.TPS54620典型应用电路图



图4.快速瞬变的3.3V 输出电源(PMP4854-2)电路图



图5.PCB 布局

TPS54620EVM-374 6-A, SWIFT稳压器评估板

TPS54620EVM-374 6-A, SWIFT Regulator Evaluation Module

The TPS54620 dc/dc converter is designed to provide up to a 6 A output. The TPS54620 implements a split input power rails with separate input voltage inputs for the power stage and control circuitry. The power stage input (PVIN) is rated for 1.6 V to 17 V while the control input (VIN) is rated for 4.5 to 17 V.

The TPS54620EVM-374 provides both inputs but is designed and tested using the PVIN connected to VIN. Rated input voltage and output current range for the evaluation module are given in Table 1. This evaluation module is designed to demonstrate the small printed-circuit-board areas that may be achieved when designing with the TPS54620 regulator. The switching frequency is externally set at a nominal 480 kHz. The high-side and low-side MOSFETs are incorporated inside the TPS54620 package along with the gate drive circuitry. The low drain-to-source on resistance of the MOSFET allows the TPS54620 to achieve high efficiencies and helps keep the junction temperature low at high output currents. The compensation components are external to the integrated circuit (IC), and an external divider allows for an adjustable output voltage. Additionally, the TPS54620 provides adjustable slow start, tracking and undervoltage lockout inputs. The absolute maximum input voltage is 20 V for the TPS54620EVM-374.

表1.TPS54620EVM-374 性能指标总结







图6. TPS54620EVM-374电路图

TPS54620EVM-374材料清单(BOM):