LTC3718 Low Input Voltage, DC/DC Controller for DDR/QDR Memory Termination

The LTC®3718 is a high current, high efficiency synchronous switching regulator controller for DDR and QDR™ memory termination. It operates from an input as low as 1.5V and provides a regulated output voltage equal to (0.5)VIN. The controller uses a valley current control architecture to enable high frequency operation with very low on-times without requiring a sense resistor. Operating frequency is selected by an external resistor and is compensated for variations in VIN and VOUT. The LTC3718 uses a pair of standard 5V logic level N-channel external MOSFETs, eliminating the need for expensive P-channel or low threshold devices.

Forced continuous operation reduces noise and RF interference. Fault protection is provided by internal foldback current limiting, an output overvoltage comparator and an optional short-circuit timer. Soft-start capability for supply sequencing can be accomplished using an external timing capacitor. OPTI-LOOP® compensation allows the transient response to be optimized over a wide range of loads and output capacitors.

OPTI-LOOP is a registered trademark of linear Technology Corporation. No RSENSE is a trademark of linear Technology Corporation. QDR RAMs and Quad Data Rate RAMs comprise a new family of products developed by Cypress Semiconductor, IDT and Micron Technology, Inc

产品特点 Features

Very Low VIN(MIN): 1.5V
Ultrafast Transient Response
True Current Mode Control
5V Drive for N-Channel MOSFETs Eliminates Auxillary 5V Supply
No Sense Resistor Required
Uses Standard 5V Logic-Level N-Channel MOSFETs
VOUT(MIN): 0.4V
VOUT Tracks 1/2 VIN or External VREF
Symmetrical Source and Sink Output Current Limit
Adjustable Switching Frequency
tON(MIN) <100ns
Power Good Output Voltage Monitor
Programmable Soft-Start
Output Overvoltage Protection
Optional Short-Circuit Shutdown Timer
Small 24-Lead SSOP Package

应用

Bus Termination: DDR/QDR Memory, SSTL, HSTL,...
Servers, RAID Systems
Distributed Power Systems
Synchronous Buck with General Purpose Boost

典型应用图

参数

LTC3718 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) *
LTC3718EG	SSOP	24	E	$4.91	$3.45
LTC3718EG#PBF	SSOP	24	E	$4.91	$3.45
LTC3718EG#TR	SSOP	24	E		$3.55
LTC3718EG#TRPBF	SSOP	24	E		$3.55

LTC3718 数据手册及相关资料下载

数据手册(英文) : LTC3718 - Low Input Voltage, DC/DC Controller for DDR/QDR Memory Termination.PDF
可靠性数据 : R384 Reliability Data .PDF