FN8207 Rev 2.00

Page 1 of 24

September 21, 2010

FN8207

Rev 2.00

September 21, 2010

X9521

Dual DCP, EEPROM Memory Fiber Channel/Gigabit Ethernet Laser Diode Control

for Fiber Optic Modules

DATASHEET

FEATURES

• Two Digitally Controlled Potentiometers (DCP’s)

—100 Tap - 10k



—256 Tap - 100k



—Non-Volatile

—Write Protect Function

• 2kbit EEPROM Memory with Write Protect & Block

• 2-Wire industry standard Serial Interface

—Complies to the Gigabit Interface Converter

(GBIC) specification

• Single Supply Operation

—2.7V to 5.5V

• Hot Pluggable

• 20 Ld TSSOP

DESCRIPTION

The X9521 combines two Digitally Controlled Potentiom-

eters (DCP’s), and integrated EEPROM with Block

accessed by an industry standard 2-Wire serial interface.

The DCP’s of the X9521 may be utilized to control the

bias and modulation currents of the laser diode in a Fiber

Optic module. The 2kbit integrated EEPROM may be

used to store module definition data.

The features of the X9521 are ideally suited to simplifying

the design of fiber optic modules which comply to the

Gigabit Interface Converter (GBIC) specification. The in-

tegration of these functions into one package significantly

reduces board area, cost and increases reliability of laser

diode modules.

BLOCK DIAGRAM

DATA

REGISTER

COMMAND

DECODE &

CONTROL

LOGIC

SDA

SCL

CONSTAT

REGISTER

PROTECT LOGIC

EEPROM

THRESHOLD

RESET LOGIC

4

2kbit

8

7 - BIT

NONVOLATILE

MEMORY

WIPER

REGISTER

COUNTER

WP

8 - BIT

NONVOLATILE

MEMORY

WIPER

REGISTER

COUNTER

ARRAY

NOT RECOMMENDED FOR NEW DESIGNS

POSSIBLE SUBSTITUTE PRODUCT

X95820, ISL22326, ISL22329, ISL22323