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.

6
2
7
6
C

-

P

r
o
d

u
c
t

B

r
i
e
f

General Description

The EL6276C is a four channel laser diode current amplifier that pro-
vides controlled current to a grounded laser diode. The four amplifiers
can provide up to 140mA per channel of DC or pulsed current. Chan-
nels 2, 3, and 4 must be used as the write channels, with switching
speeds of approximately three nanosecond rise/fall time. All four
channels are summed together at the I

OUT

output, allowing the user to

create multilevel waveforms in order to optimize laser diode perfor-
mance. The level of the output current is set by an analog voltage
applied to an external resistor which converts the voltage into a current
at the I

pin (virtually ground). The current seen at this pin is then

amplified by 100X to become a current source at pin I

OUT

An on-chip 500MHz oscillator is provided to allow current modula-
tion when in any mode. This is turned on when the OSCEN pin is held
high. Complete control of amplitude and frequency is set by two exter-
nal resistors connected to ground at pins RFREQ and RAMP (see
graphs in this data sheet for further explanation).

Output current pulses are enabled when an `L' signal is applied to the
OUTEN pin. No output current flows when OUTEN is `H', and addi-
tional laser diode protection is provided since the OUTEN input will
float high when open. Complete I

OUT

shutoff is also achieved by hold-

ing the ENABLE pin low, which will override all other control pins.

The external resistors allow the user to accurately and independently
set each amplifier transconductance by applying a voltage to each
resistor, without restriction on the voltage range, thus ensuring broad
voltage DAC compatibility. Alternatively, the I

pin can be biased

from a current DAC or other current source.

Connection Diagram

GND

IINR

GND

IIN2

RFREQ

IIN3

IIN4

OUTENR

OUTEN2

OUTEN3

OUTEN4

GND

VCC

IOUT

GND

RAMP

ENABLE

OSCEN

VCC

GND

Features

· "Shrink-Small" Outline Package
· Voltage-controlled output current

source to 140mA per channel,

requiring one external set resistor

per channel

· Current-controlled output current

source to 140mA per channel

· Rise time = 3.0ns
· Fall time = 3.5ns
· On chip oscillator with frequency

and amplitude control by use of

external resistors to ground

· Oscillator to 500MHz
· Oscillator to 100mA pk/pk
· Single +5V supply (±10%)
· Current amplification = 100X
· Disable feature for power-up

protection and power savings

· TTL/CMOS control signals

Applications

· CD-RW applications
· Writable optical drives
· Laser diode current switching

Ordering Information

Part No

Temp. Range

Package

Outline #

EL6276CU

0°C to +70°C

QSOP-24

MDP0040

EL6276C - Product Brief

4-Ch Laser Diode Driver + Oscillator

S
e
p

t
e
m

e
r

2
8
,

2
0
0
0

EL6276C - Product Brief

4-Ch Laser Diode Driver + Oscillator

6
2
7
6
C

-

P

r
o
d
u

c
t

B

r
i
e
f

General Disclaimer

Specifications contained in this data sheet are in effect as of the publication date shown. Elantec, Inc. reserves the right to make changes in the cir-
cuitry or specifications contained herein at any time without notice. Elantec, Inc. assumes no responsibility for the use of any circuits described
herein and makes no representations that they are free from patent infringement.

WARNING - Life Support Policy

Elantec, Inc. products are not authorized for and should not be used
within Life Support Systems without the specific written consent of
Elantec, Inc. Life Support systems are equipment intended to sup-
port or sustain life and whose failure to perform when properly used
in accordance with instructions provided can be reasonably
expected to result in significant personal injury or death. Users con-
templating application of Elantec, Inc. Products in Life Support
Systems are requested to contact Elantec, Inc. factory headquarters
to establish suitable terms & conditions for these applications. Elan-
tec, Inc.'s warranty is limited to replacement of defective
components and does not cover injury to persons or property or
other consequential damages.

S
e
p
t
e
m

e
r

2
8
,

2
0
0
0

Printed in U.S.A.

Elantec Semiconductor, Inc.

675 Trade Zone Blvd.

Milpitas, CA 95035

Telephone: (408) 945-1323

(888) ELANTEC

Fax:

(408) 945-9305

European Office: +44-118-977-6020
Japan Technical Center: +81-45-682-5820

Part Number EL6276C