EL6273C - Product Brief
EL6273C - Product Brief
3-Channel Laser Diode Driver w/Oscillator & APC Amplifier
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 = 400X
• Disable feature for power-up
protection and power savings
• TTL/CMOS control signals
• Fast Settling APC Amplifier
General Description
The EL6273C is a high-performance three channel laser driver that
provides controlled current to a grounded laser diode. Three amplifiers
can provide up to 140mA per channel of DC or pulsed current. Chan-
nels 2 and 3 should be used as the write channels, with switching
speeds of approximately three nanoseconds rise/fall time. All three
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
IN
pin (virtually ground). The current seen at this pin is then
amplified by 400X to become a current source at pin I
OUT
.
An on-chip 500MHz oscillator is provided to allow output current
modulation 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 external 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
shut-off is also achieved by
holding the ENABLE pin low, which will override all other control
pins.
The EL6273C also includes a fast settling APC amplifier designed to
interface directly with the front end monitor diode and the sample-
and-hold amplifier for read and write power control. It’s 40MHz band-
width and 150 ns settling time enable up to 8X CD-RW design.
Applications
• CD-RW applications
• Writable optical drives
• Laser diode current switching
Ordering Information
Part No
EL6273CU
Temp. Range
0°C to +70°C
Package
QSOP-16
Outline #
MDP0040
Connection Diagram
1 VOUT
2 VREF
3 IINR
4 RFREQ
5 IIN2
6 IIN3
7 OUTEN2
8 OUTEN3
PDIN 16
VCC 15
IOUT 14
GND 13
RAMP 12
ENABLE 11
OSCEN 10
VCC 9
September 6, 2000
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 ]
