gd16521 ETC-unknow, gd16521 Datasheet - Page 6

• Manufacturer Part Number: gd16521
• Description: Gbit/s Timing Laser Driver
• Manufacturer: ETC-unknow

Pin List
Data Sheet Rev.: 11
Mnemonic:
SDIP
SDIN
TDIP
TDIN
SCIP
SCIN
TCIP
TCIN
IM
IMB
IB
IMSET
IBSET
IBM
IMM
AR
MARKP
MARKN
MTJ
IMC
PD
OPSET
FFSET
SHDW
DUTY
VCC
VCCCONT
14, 18, 20, 28, 33,
Pad and Pin No.:
29, 30
31, 32
42, 46
10
11
27
40
22
23
39
25
35
36
38
41
26
19
15
16
48
44
4
5
3
6
9
8
COLLECTOR
COLLECTOR
COLLECTOR
Pin Type:
ANL OUT
ANL OUT
ANL OUT
ANL OUT
ANL OUT
ANL OUT
ANL OUT
LVTTL IN
LVTTL IN
CML IN
CML IN
CML IN
CML IN
ANL IN
ANL IN
ANL IN
ANL IN
OPEN
OPEN
OPEN
PWR
PWR
GD16521
Description:
Data inputs. Internally terminated with 50 W to TDIP/TDIN.
Loop through termination pins for SDIP and SDIN respectively.
Clock inputs. Internally terminated with 50 W to TCIP/TCIN.
Loop through termination pins for SDIP and SDIN respectively.
Laser Driver Output (2.5 Gbit/s). IM sinks a modulation current,
which is controlled by the pin IMSET. A logic HI on SDIP corre-
sponds to IM sinking current.
Laser Driver inverted Output (2.5 Gbit/s). IMB sinks a modulation
current, which is controlled by the pin IMSET. Connect to VCC
through 20 to 25 W.
Pre-bias current output. IB sinks a current, which is controlled by
the pin IMC.
Modulation current control monitor output. This pin is the output of
the modulation current control loop OP-amp. For stability a capa-
citor may be added between this pin and the IMC pin.
Pre-bias current control monitor output. This pin is the output of
the optical power control loop OP-amp. For stability a capacitor
may be added between this pin and the OPSET pin.
Pre-bias current mirror output. The sink current into the IBM pin is
1/20 of the pre-bias current.
Modulation current mirror output. The sink current into the IMM
pin is 1/20 of the modulation current. Internally IMM is connected
to the positive input of the modulation current control loop
OP-amp.
Anti-rush current sink. AR sinks a 1 mA current when SHDW is
high. Typically connected together with PD to the monitor diode.
Mark-space monitor outputs. High impedance CML outputs.
Temperature monitor.
Modulation current setting. The modulation current will automati-
cally be adjusted to this value if the internal modulation control
loop is used. The IMC pin is the negative input of the modulation
current control loop OP-amp.
Positive input of the automatic optical power control loop OP-amp,
used to control the pre-bias current. Typically connected to the
monitor diode photo detector of the laser diode.
Negative input of the automatic optical power control loop
OP-amp, used to control the pre-bias current. Typically connected
to an external reference voltage.
When FFSET is low data is re-timed. When high data re-timing is
bypassed.
Modulation and pre-bias current shutdown input.
Set high for shutdown, low for normal operation.
Input for control of the mark-space ratio of the output. Decreasing
the voltage of the DUTY pin increases the pulse width of a current
high into the IM pin. Typically connected to VEE through resistor.
Positive supply pins for laser driver part.
Positive supply pin for modulation current control system.
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