AD9661AKR Analog Devices Inc, AD9661AKR Datasheet - Page 4

• Manufacturer Part Number: AD9661AKR
• Description: IC LASER DIODE DRIVER 28-SOIC
• Manufacturer: Analog Devices Inc
• Type: Laser Diode Driverr

Specifications of AD9661AKR

• Rohs Status: RoHS non-compliant
• Number Of Channels: 1
• Voltage - Supply: 4.75 V ~ 5.25 V
• Current - Supply: 75mA
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 28-SOIC (0.300", 7.50mm Width)
• Mounting Type: Surface Mount

AD9661A
Pin
OUTPUT
POWER LEVEL
CAL
HOLD
PULSE
PULSE 2
SENSE IN
GAIN
POWER MONITOR
DISABLE
V
+V
GROUND
LEVEL SHIFT IN
LEVEL SHIFT OUT
REF
S
Analog laser diode current output. Connect to cathode of laser diode, anode connected to +V
TTL/CMOS compatible, current output disable circuit. Logic LOW for normal operation; logic HIGH
Function
Analog voltage input, V
during calibration as follows:
TTL/CMOS compatible, feedback loop T/H control signal. Logic LOW enables calibration mode, and
the feedback loop T/H goes into track mode 13 ns after (the aperture delay) PULSE goes logic HIGH
(there is no aperture delay if PULSE goes high before CAL transitions to a LOW level). Logic HIGH dis-
ables the T/H and immediately places it in hold mode. PULSE should be held HIGH while calibrating.
Floats logic HIGH.
External hold capacitor for the bias loop T/H. Approximate droop in the output current while CAL is
logic HIGH is:
Bandwidth of the loop is:
TTL/CMOS compatible, current control signal. Logic HIGH supplies I
LOW turns I
TTL/CMOS compatible, current control signal. Logic LOW supplies I
HIGH turns I
Analog current input, I
anode of the PIN diode, with the PIN cathode connected to +V
SENSE IN varies slightly with temperature and current, but is typically 1.0 V.
External connection for the feedback network of the transimpedance amplifier. External feedback network,
R
values.
Output voltage monitor of the internal feedback loop. Voltage is proportional to feedback current from
photo diode, I
disables the current outputs to the laser diode, and drives the voltage on the hold capacitors close to V
(minimizes the output current when the device is re-enabled). DISABLE floats logic HIGH.
Analog Voltage output, internal bandgap voltage reference, ~1.8 V, provided to user for power level offset.
Power Supply, nominally +5 V. All +V
Ground reference. All GROUND connections should be tied together externally.
Analog input to the on board level shift circuit. Input Range 0.1 V – 1.6 V.
Voltage output from on board level shift circuit. Connect to POWER LEVEL externally to use the on
board level shift circuit. Output voltage is V
GAIN
and C
GAIN
OUT
OUT
MONITOR
, should be connected between GAIN and POWER MONITOR. See text for choosing
POWER MONITOR
LEVEL SHIFT OUT
off. Floats logic HIGH.
off. Floats logic HIGH.
LEVEL SHIFT IN
I
POWER LEVEL
SENSE INPUT
OUT
.
MONITOR
REF
GROUND
GROUND
DISABLE
PULSE2
HOLD
BW
GAIN
to V
V
18 10
DNC
+V
REF
PIN DESCRIPTIONS
I
S
MONITOR
, from PIN photo detector diode. SENSE IN should be connected to the
REF
10
11
12
13
14
C
1
2
3
4
5
6
7
8
9
PIN ASSIGNMENTS
HOLD
2 (550 ) C
+ 1.6 V. Output current is set proportional to the POWER LEVEL
–9
t
AD9661AKR
HOLD
(Not to Scale)
–4–
S
connections should be tied together externally.
V
1
POWER LEVEL
LEVEL SHIFT OUT
R
GAIN
HOLD
28
27
26
25
24
23
22
21
20
19
18
17
16
15
50
+V
GROUND
OUTPUT
GROUND
OUTPUT
GROUND
OUTPUT
GROUND
OUTPUT
GROUND
+V
GROUND
CAL
PULSE1
– V
S
S
= V
REF
LEVEL SHIFT IN
S
or another positive voltage. Voltage at
OUT
OUT
to the laser diode. Logic
to the laser diode. Logic
+V
REF
.
S
externally.
REV. 0
REF