Philips Semiconductors

Product data

NE57810

Advanced DDR memory termination power

with external reference in

2

2003 Sep 12

DESCRIPTION

The NE57810 is designed to provide power for termination of a

Double Data Rate (DDR) SDRAM memory bus. It significantly

reduces parts count, board space, and overall system cost

compared to previous solutions.

The NE57810 DDR termination regulator maintains an output

voltage (DDR reference bus voltage) that is one-half that of the RAM

supply voltage. It is capable of providing up to

±3.5 A for sustained

periods. Overcurrent limiting protects the NE57810 from inrush

currents at start-up, and overtemperature shutdown protects the

device in extreme temperature situations.

The SPAK-5 (SOT756) package is thermally robust for flexibility of

thermal design. Because the NE57810 is a linear regulator, no

external inductors or switching FETs are necessary. Fast response

to load changes reduces the need for output capacitors.

FEATURES

(switching FETs, inductors, decoupling capacitors)

supply voltage

SDRAM systems

APPLICATIONS

SIMPLIFIED SYSTEM DIAGRAM

DIMM0

DIMM1

Control & Address

Data

NE57810

ExtRefIn

(optional)

RefOut

MEMORY

CONTROLLER

20

Ω (typical)

27

Ω (typical)

TERMINATION

POWER

0.1

µF

100

µF

SL01669

Figure 1.

Simplified system diagram.