Note: All information contained in this data sheet has been carefully checked and is believed to be accurate as of the date of publication; however, this data sheet cannot be a “controlled document”. Current revisions, if any, to these

specifications are maintained at the factory and are available upon your request. We recommend checking the revision level before finalization of your design documentation.

© 2001 Elantec Semiconductor, Inc.

General Description

The EL6281C is a combination read + 3 write level laser driver with

IV amplifier. A dual amplitude, dual frequency RF oscillator sums on

the output for laser noise reduction during read or write. All these

functions are provided in 24-lead QSOP and LPP packages.

The ENABLE pin enables the read & write channels. Positive current

supplied to the IIN lines, through user selected resistors, allow the full

scale range of each amplifier to be matched to the full scale range of

the users control DACs. When the WEN pins are switched low, the

respective current is summed to the output with 1ns rise and fall times.

line. The R/W line allows the oscillator to operate at one amplitude

and frequency when R/W is high, and another amplitude and fre-

quency when R/W is low.

The entire chip is powered down when ENABLE is low. The user can

calibrate the gain of the I/V amplifier. With a slew rate around

200V/µs, the I/V amplifier can normally settle to less than 1% within

30ns.

1

2

3

4

16

15

14

13

5

6

7

12

11

9

8

10

20

19

18

17

24

23

22

21

Connection Diagram

VREF

IINR

VOUT

IIN2

RFREQ1

IIN3

IIN4

RFREQ2

RWB

GND

WEN4

WEN3

PDIN

VCC

VCC

IOUT

GND

GND

RAMP1

RAMP2

ENABLE

OSCEN

VCC

WEN2

19

18

17

16

15

14

13

1

2

3

4

5

6

7

24-Pin LPP Top View

Thermal Pad

IIN2

RF1

IIN3

IIN4

RF2

RWB

GND

VCC

IOUT

GND

GND

RAMP1

RAMP2

ENABLE

Features

• Read + 3 Write Channel laser

driver with oscillator & fast I/V

amplifier

• Rise time = 0.8 nsec

• Fall time = 0.8 nsec

• 200V/µs I/V amplifier

• 100X gain, 100mA low noise read

channel

• 200X gain, 200mA write channel

• Two 100X gain, 100mA write

channels

with dual frequency and amplitude

control

• 3.3V compatible logic signals

• Single +5V supply

Applications

• CD-RW to 16X

• CD-R to 32X

• Writable Optical Disk Drives

Ordering Information

Part No.

Temp. Range

Package

Outline #

EL6281CU

0°C to +70°C

QSOP-24

MDP0040

EL6281CL

0°C to +70°C

LPP-24

MDP0046

EL6281C - Product Brief

4-Channel Laser Driver with APC Amp