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.
EL6287C - Product Brief
General Description
The EL6287C is a four channel laser diode current amplifier that pro-
vides controlled current to a grounded laser diode. Channels 2, 3, and
4 must be used as the write channels, with switching speeds of approx-
imately one nanosecond rise/fall time. All four channels are summed
together at the IOUT output, allowing the user to create multilevel
waveforms in order to optimize laser diode performance. 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 IIN pin (virtu-
ally ground). The current seen at this pin is then amplified to become a
current source at pin IOUT.
An on-chip 500MHz oscillator is provided to allow current modula-
tion when in read 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). The oscillator will
turn off whenever any of the OUTEN pins for channels 2, 3, or 4 (the
write channels) are low (see truth table).
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 IIN pin can be biased
from a current DAC or other current source.
Connection Diagram
1
2
3
4
16
15
14
13
5
6
7
12
11
9
8
10
20
19
18
17
24
23
22
21
GND
IINR
GND
IIN2
RFREQ
IIN3
IIN4
OUTENR
OUTEN2
OUTEN3
OUTEN4
GND
GND
VCC
VCC
IOUT
IOUT
GND
RAMP
ENABLE
OSCEN
VCC
VCC
GND
Features
•“Shrink-Small” Outline Package
•Voltage-controlled output current
source requiring one external set
resistor per channel
•Current-controlled output current
source
•Rise time = 0.8 nsec
•Fall time = 0.8 nsec
•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%)
•Disable feature for power-up
protection and power savings
•CMOS control signals
Applications
•CD-RW applications
•Writable optical drives
•Laser diode current switching
Ordering Information
Part No Temp. Range Package Outline #
EL6287CU 0°C to +70°C 24-Pin QSOP MDP0040
EL6287C - Product Brief
4-Ch Laser Diode Driver + Oscillator
August 31, 2001
2
EL6287C - Product Brief
4-Ch Laser Diode Driver + Oscillator
EL6287C - Product Brief
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.
August 31, 2001
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
