系统板 MAXREFDES1086

MAXREFDES1086:小尺寸、5V/500mA、同步、无光耦、反激DC-DC转换器,91.4%效率


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Input Type VIN (MIN)
(V)
VIN (MAX)
(V)
IOUT
(A)
Single/Multiple
Output
VOUT
(V)
POUT
(W)
Topology
DC 8 28
0.5 Single 5 2.5 Flyback

Due to its simplicity and low cost, the flyback converter is the preferred choice for low-to-medium isolated DC-DC power-conversion applications. However, the use of an optocoupler or an auxiliary winding on the flyback transformer for voltage feedback across the isolation barrier increases the number of components and design complexity. The MAX17690 eliminates the need for an optocoupler or auxiliary transformer winding and achieves ±5% output voltage regulation over line, load, and temperature variations.

The MAX17690 implements an innovative algorithm to accurately determine the output voltage by sensing the reflected voltage across the primary winding during the flyback time interval. By sampling and regulating this reflected voltage when the secondary current is close to zero, the effects of secondary-side DC losses in the transformer winding, the PCB tracks, and the rectifying diode on output voltage regulation can be minimized.

The MAX17690 also compensates for the negative temperature coefficient of the rectifying diode.

Key Features

  • 4.5V to 60V Input Voltage Range
  • Programmable Switching Frequency from 50kHz to 250kHz
  • Programmable Input Enable/UVLO Feature
  • Programmable Input Overvoltage Protection
  • Adjustable Soft-Start
  • 2A/4A Peak Source/Sink Gate Drive Capability
  • Hiccup Mode Short-Circuit Protection
  • Fast Cycle-by-Cycle Peak Current Limit
  • Thermal Shutdown Protection
  • Space-Saving, 16-Pin, 3mm x 3mm TQFN Package
  • -40°C to +125°C Operating Temperature Range
MAXREFDES1086 Hardware 放大+


This board is not available for purchase.

An isolated no-opto flyback DC-DC converter using the MAX17690 and MAX17606 is demonstrated for a 5V DC output application. The power supply delivers up to 500mA at 5V.

Designed, Built, Tested

This document describes the hardware shown in Figure 1. It provides a detailed systematic technical guide to designing an isolated no-opto flyback DC-DC converter using Maxim’s MAX17690 controller. The power supply has been built and tested.

Design Resources

 
Status:
Package:
Temperature:

MAX17690
60V、无光耦、隔离反激控制器

  • 4.5V至60V输入电压范围
  • 无需光耦或第三个绕组即可驱动反激信号通过隔离栅。
  • 2A/4A最大源出/吸入栅极驱动电流

MAX17606
副边同步MOSFET驱动器,用于反激转换器

  • 4.5V至36V较宽输入电压
  • 2A/4A最大源出/吸入栅极驱动电流
  • 适合非连续传导模式(DCM)、边界传导模式(BCM)