EL6287C - Product Brief
EL6287C - Product Brief
4-Ch Laser Diode Driver + Oscillator
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
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 I
OUT
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 I
IN
pin (virtu-
ally ground). The current seen at this pin is then amplified to become a
current source at pin I
OUT
.
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 I
IN
pin can be biased
from a current DAC or other current source.
Applications
• CD-RW applications
• Writable optical drives
• Laser diode current switching
Ordering Information
Part No
EL6287CU
Temp. Range
0°C to +70°C
Package
24-Pin QSOP
Outline #
MDP0040
Connection Diagram
1 GND
2 IINR
3 GND
4 IIN2
5 RFREQ
6 IIN3
7 IIN4
GND 24
VCC 23
VCC 22
IOUT 21
IOUT 20
GND 19
RAMP 18
8 OUTENR ENABLE 17
9 OUTEN2
10 OUTEN3
11 OUTEN4
12 GND
OSCEN 16
VCC 15
VCC 14
GND 13
August 31, 2001
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.
ELANTEC [ ELANTEC SEMICONDUCTOR ]
