LTC1698 Isolated Secondary Synchronous Rectifier Controller

The LTC®1698 is a precision secondary-side forward converter controller that synchronously drives external N-channel MOSFETs. It is designed for use with the LT®3781 primary-side synchronous forward converter controller to create a completely isolated power supply. The LT3781 synchronizes the LTC1698 through a small pulse transformer and the LTC1698 drives a feedback optocoupler to close the feedback loop. Output accuracy of ±0.8% and high efficiency over a wide range of load currents are obtained.

The LTC1698 provides accurate secondary-side current limit using an external current sense resistor. The input voltage at the MARGIN pin provides ±5% output voltage adjustment. A power good flag and overvoltage input are provided to ensure proper power supply conditions. An auxiliary 3.3V logic supply is included that supplies up to 10mA of output current

产品特点 Features

High Efficiency Over Wide Load Current Range
±0.8% Output Voltage Accuracy
Dual N-Channel MOSFET Synchronous Drivers
Pulse Transformer Synchronization
Optocoupler Feedback Driver
Programmable Current Limit Protection
±5% Margin Output Voltage Adjustment
Adjustable Overvoltage Fault Protection
Power Good Flag
Auxiliary 3.3V Logic Supply
Available in 16-Lead SSOP and SO Packages

参数

应用

48V Input Isolated DC/DC Converters
Isolated Telecommunication Power Systems
Distributed Power Step-Down Converters
Industrial Control Systems
Automotive and Heavy Equipment

典型应用图

LTC1698 订购信息和价格参考Package Variations and Pricing

器件型号	封装	引脚	温度	价格 (以 1 ~ 99 片为批量)	价格 (以 1000 片为批量) *
LTC1698EGN	SSOP	16	E	$6.27	$5.30
LTC1698EGN#PBF	SSOP	16	E	$6.27	$5.30
LTC1698EGN#TR	SSOP	16	E		$5.36
LTC1698EGN#TRPBF	SSOP	16	E		$5.36
LTC1698ES	SO	16	E	$6.33	$5.35
LTC1698ES#PBF	SO	16	E	$6.33	$5.35
LTC1698ES#TR	SO	16	E		$5.41
LTC1698ES#TRPBF	SO	16	E		$5.41
LTC1698IGN	SSOP	16	I	$6.92	$5.85
LTC1698IGN#PBF	SSOP	16	I	$6.92	$5.85
LTC1698IGN#TR	SSOP	16	I		$5.91
LTC1698IGN#TRPBF	SSOP	16	I		$5.91
LTC1698IS	SO	16	I	$6.98	$5.90
LTC1698IS#PBF	SO	16	I	$6.98	$5.90
LTC1698IS#TR	SO	16	I		$5.96
LTC1698IS#TRPBF	SO	16	I		$5.96

LTC1698 数据手册及相关资料下载

数据手册(英文) : LTC1698 - Isolated Secondary Synchronous Rectifier Controller.PDF
设计要点 (英文) : DN261 - Chip Set Offers Low Cost Alternative to 48V Telecom Modules.PDF
设计要点 (中文) : DN261 Chip Set Offers Low Cost Alternative to 48V Telecom Modules.PDF
设计要点 (英文) : DN299 - Multiple Output Isolated Power Supply Achieves High Efficiency with Secondary Side Synchronous Post Regulator.PDF
设计要点 (中文) : DN299 Multiple Output Isolated Power Supply Achieves High Efficiency with Secondary Side Synchronous Post Regulator.PDF
可靠性数据 : R245 Reliability Data .PDF