3-Ch Laser Diode Driver + Oscillator
General Description
• “Shrink-Small” Outline Package
• Voltage output current source
requiring one external set resistor
per channel
• Auto Oscillator On-Off with
OUTEN Signals
• Rise time = 0.8ns
• Fall time = 0.8ns
• 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 = 100
• Disable feature for power-up
protection and power savings
• CMOS control signals
The EL6247C is a three channel laser diode current amplifier that provides controlled current to a grounded laser diode. Channels 2 and 3
should be used as the write channels, with switching speeds of approximately one nanosecond rise/fall time. All three 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 (virtually
ground). The current seen at this pin is then amplified to become a current source at pin IOUT.
• CD-RW applications
• Writable optical drives
• Laser diode current switching
Ordering Information
Part No.
Temp. Range
Outline #
0°C to +70°C
Output current pulses are enabled when an ‘L’ signal is applied to the
OUTEN pin. No output current flows when OUTEN is ‘H’ and additional laser diode protection is provided since the OUTEN input will
float high when open. Complete IOUT shutoff is also achieved by holding the ENABLE pin low, which will override the OUTEN control pins.
An on-chip 500MHz oscillator is provided to allow output current modulation when in read mode. The oscillator is enabled when the OSCEN
pin is held high. If any of channels 2 or 3 are active, the oscillator is
switched off. Complete control of amplitude and frequency is set by
two external resistors connected to ground at pins RFREQ and RAMP
(see graphs in this data sheet for further explanation).
The external IIN 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
VCC 16
2 IIN2
VCC 15
GND 13
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.
October 25, 2001
5 IIN3
© 2001 Elantec Semiconductor, Inc.
EL6247C - Product Brief
EL6247C - Product Brief
EL6247C - Product Brief
EL6247C - Product Brief
3-Ch Laser Diode Driver + Oscillator
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 circuitry 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.
October 25, 2001
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 support 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 contemplating 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. Elantec, Inc.’s warranty is limited to replacement of defective
components and does not cover injury to persons or property or
other consequential damages.
Elantec Semiconductor, Inc.
675 Trade Zone Blvd.
Milpitas, CA 95035
Telephone: (408) 945-1323
(408) 945-9305
European Office: +44-118-977-6020
Japan Technical Center: +81-45-682-5820
Printed in U.S.A.