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.
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General Description
The EL6281C is a combination read + 3 write level laser driver with
IV amplifier. A dual amplitude, dual frequency RF oscillator sums on
the output for laser noise reduction during read or write. All these
functions are provided in 24-lead QSOP and LPP packages.
The ENABLE pin enables the read & write channels. Positive current
supplied to the IIN lines, through user selected resistors, allow the full
scale range of each amplifier to be matched to the full scale range of
the users control DACs. When the WEN pins are switched low, the
respective current is summed to the output with 1ns rise and fall times.
The 100mAP-P (max) oscillator is switched on and off by the OSCEN
line. The R/W line allows the oscillator to operate at one amplitude
and frequency when R/W is high, and another amplitude and fre-
quency when R/W is low.
The entire chip is powered down when ENABLE is low. The user can
calibrate the gain of the I/V amplifier. With a slew rate around
200V/s, the I/V amplifier can normally settle to less than 1% within
30ns.
1
2
3
4
16
15
14
13
5
6
7
12
11
9
8
10
20
19
18
17
24
23
22
21
Connection Diagram
VREF
IINR
VOUT
IIN2
RFREQ1
IIN3
IIN4
RFREQ2
RWB
GND
WEN4
WEN3
PDIN
VCC
IOUT
GND
RAMP1
RAMP2
ENABLE
OSCEN
VCC
WEN2
19
18
17
16
15
14
13
24
23
22
21
20
8
9
10
11
12
1
2
3
4
5
6
7
24-Pin LPP Top View
Thermal Pad
IIN2
RF1
IIN3
IIN4
RF2
RWB
GND
VCC
IOUT
GND
RAMP1
RAMP2
ENABLE
IIN
R
VR
EF
VO
U
T
PD
IN
VC
C
W
EN
4
W
EN
3
W
EN
2
VC
C
OS
CE
N
Features
Read + 3 Write Channel laser
driver with oscillator & fast I/V
amplifier
Rise time = 0.8 nsec
Fall time = 0.8 nsec
200V/s I/V amplifier
100X gain, 100mA low noise read
channel
200X gain, 200mA write channel
Two 100X gain, 100mA write
channels
500MHz, 100mAP-P Oscillator
with dual frequency and amplitude
control
3.3V compatible logic signals
Single +5V supply
Applications
CD-RW to 16X
CD-R to 32X
Writable Optical Disk Drives
Ordering Information
Part No.
Temp. Range
Package
Outline #
EL6281CU
0°C to +70°C
QSOP-24
MDP0040
EL6281CL
0°C to +70°C
LPP-24
MDP0046
EL6281C - Product Brief
4-Channel Laser Driver with APC Amp
O
ct
ob
er
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