MITSUBISHI
〈DIGITAL
ASSP〉
MITSUBISHI
〈DIGITAL
ASSP〉
M66515FP
M66515FP
LASER-DIODE DRIVER/CONTROLLER
LASER-DIODE DRIVER/CONTROLLER
DESCRIPTION
The M66515 is a semiconductor laser-diode driver/controller.
Its functions are the driving and laser power control of a spe-
cific type (Mitsubishi’s N type laser) of semiconductor laser
diode, in which the anode of a semiconductor laser diode is
connected in stem structure to the cathode of a monitoring
photodiode.
The IC has a laser drive current output pin of sink type and is
capable of driving a laser diode on a maximum bias current
of 30mA and a maximum switching current of 120mA, which
is switched at a rate of 40Mbit/s.
Since the M66515 has a built in sample-hold circuit, it is pos-
sible to realize an internal APC
∗
system that requires no ex-
ternal device for laser power control.
∗:
Automatic Power Control
FEATURES
• Built-in sample-hold circuit for internal APC function
• High speed switching (40Mbps)
• Large drive current (150mA max.)
• Capable of setting bias current (30mA max.)
• 5V single power supply
APPLICATION
Semiconductor laser-diode applied equipment
PIN CONFIGURATION (TOP VIEW)
OUTPUT TO SWITCHING
CURRENT SETTING LOAD
OUTPUT TO BIAS CURR-
ENT SETTING LOAD
BIAS CURRENT
SETTING VOLTAGE INPUT
REFERENCE VOLTAGE
OUTPUT
REFERENCE VOLTAGE INPUT
HOLDING CAPACITANCE
LOAD INPUT/OUTPUT
SAMPLE-HOLD CONTROL
INPUT
R
S
←
GND1
R
B
←
Vref
←
C
H
←
→
Vr
→
V
B
→
S/H
→
V
CC
1
TEST PIN TEST
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
V
CC
2
→
RO
NC
LASER CURRENT
LOAD OUTPUT
LASER CURRENT
OUTPUT
Outline 20P2N-A
NC: No Connection
M66515FP
→
LD
GND2
MONITORING DIODE
←
PD
INPUT
←
DATA
SWITCHING DATA INPUT
←
ENB
LASER CURRENT
ENABLE INPUT
←
2RM
MONITORING LOAD
←
1RM
�½
INPUT
BLOCK DIAGRAM
�½
MONITORING
LOAD INPUT
1RM
11
2RM
12
MONITORING
DIODE INPUT
PD
15
I
PD
LASER CURRENT
REFERENCE
LASER CURRENT
OUTPUT
VOLTAGE OUTPUT LOAD RESISTOR
V
ref
RO
LD
17
19
5
REFERENCE
VOLTAGE SOURCE
(1.2V typ)
DIFFRENTIAL AMP
REFERENCE
VOLTAGE INPUT
I
B
+
I
SW
Vr 6
8
SAMPLE-HOLD
CIRCUIT
I
B
7
1
4
BIAS CURRENT
SOURCE (I
B
)
30mA max.
CURRENT SWITCHING
CIRCUIT
I
SW
SWITCHING CURRENT
SOURCE (I
SW
)
120mA max.
14
DATA
SWITCHING
DATA INPUT
9
V
CC1
20
V
CC2
2 GND1
16
GND2
13
ENB
LASER CURRENT
ENABLE CONTROL
INPUT
SAMPLE-HOLD S/H
CONTROL INPUT
HOLDING CAPACITANCE
LOAD INPUT/OUTPUT C
H
OUTPUT TO SWITCHING
CURRENT SETTING R
S
LOAD
BIAS CURRENT SETTING
V
B
VOLTAGE INPUT
OUTPUT TO BIAS
R
B
3
CURRENT SETTING LOAD
V
CC1
, GND1: For analog circuits in IC
V
CC2
, GND2: For digital circuits in IC
1
MITSUBISHI [ MITSUBISHI ELECTRIC SEMICONDUCTOR ]
