Intersil公司的ISL85415A是一款輸入范圍為3V到36V的500mA同步降壓穩壓調節器，為各種各樣應用提供易用、高效及少量外圍器件的電源解決方案。該芯片同時集成高邊及低邊NMOS FET場效應管。在輕載情況下，工作在PFM工作模式以最大限度提高效率，如采用PWM工作模式下PFM提高效率工作模式失效。開關頻率默認為500kHz，可通過外部電阻設置開關頻率為300kHz到2MHz。本文首先介紹芯片的簡介、特性、內部框圖及應用領域，并給出相應設計方案的設計原理圖、元器件列表及PCB元件布局圖。

The ISL85415A is a 500mA Synchronous buck regulator with an input range of 3V to 36V. It provides an easy to use, high efficiency low BOM count solution for a variety of applications.

The ISL85415A integrates both high-side and low-side NMOS FET’s and features a PFM mode for improved efficiency at light loads. This feature can be disabled if forced PWM mode is desired. The part switches at a default frequency of 500kHz but may also be programmed using an external resistor from 300kHz to 2MHz. The ISL85415A has the ability to utilize internal or external compensation. By integrating both NMOS devices and providing internal configuration options, minimal external components are required, reducing BOM count and complexity of design.

With the wide VIN range and reduced BOM the part provides an easy to implement design solution for a variety of applications while giving superior performance. It will provide a very robust design for high voltage Industrial applications as well as an efficient solution for battery powered applications.

The part is available in a small Pb free 4mmx3mm DFN plastic package with an operation temperature range of -40°C to +85°C

ISL85415A主要特性：

• Wide input voltage range 3V to 36V
• Synchronous operation for high efficiency
• No compensation required
• Integrated High-side and Low-side NMOS devices
• Selectable PFM or forced PWM mode at light loads
• Internal fixed (500kHz) or adjustable switching frequency 300kHz to 2MHz
• Continuous output current up to 500mA
• Internal or external soft-start
• Minimal external components required
• Power-good and enable functions available.

ISL85415A應用：

• Industrial control
• Medical devices
• Portable instrumentation
• Distributed power supplies
• Cloud Infrastructure

 
圖1. ISL85415A內部方框圖

ISL85415A方案介紹：

The ISL85415EVAL1Z, ISL85415AEVAL1Z kit is intended for use for Point-of-Load applications sourcing from 3V to 36V.The kit is used to demonstrate the performance of the ISL85415, ISL85415A Wide VIN Low Quiescent Current High Efficiency Sync Buck Regulator with 500mA output current. The ISL85415, ISL85415A are offered in a 4mmx3mm 12 Ld DFN package with 1mm maximum height. The converter occupies 1.516 cm2 area.

ISL85415A方案原理圖：

圖2. ISL85415A方案原理圖

ISL85415A方案材料清單：





PCB元件布局圖：