Datasheet

www.ti.com
APPLICATION INFORMATION
S0154-01
ONET4211LD
24-LeadQFN
Monitor
Photodiode
Laser-
Diode
GND
VCC
MOD–
MOD+
VCC
BIAS
DISABLE
APCSET
OUTPOL
IBMAX
CAPC
PD
GND
R
APCSET
R
BIASMAX
R
MONP
R
MONB
R
MODSET
R
MODTC
C
APC
VCC
DIN+
20 W
R
D
DIN–
VCC
GND
MONP MONB SDOWN FL
TMODE
MODSET MODTC
DISABLE
VCC
FLTMODE
SDOWN
DIN+
DIN–
MONP
MONB
OUTPOL
ONET4211LD
SLLS688A – NOVEMBER 2005 – REVISED SEPTEMBER 2007
Figure 25 shows the ONET4211LD connected with a dc-coupled interface to the laser diode; alternatively, the
ONET4211LD laser driver can be ac-coupled.
Figure 25. Basic Application Circuit With DC-Coupled Interface Between
the ONET4211LD and the Laser Diode
APC loop instability can occur with large inductive loading on the BIAS pin. To ensure loop stability in this case, it
is recommended to connect a 1-nF capacitor to ground at the BIAS pin.
Copyright © 2005 – 2007, Texas Instruments Incorporated Submit Documentation Feedback 17
Product Folder Link(s): ONET4211LD