Datasheet

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P0024-03
GND
DISABLE
VCC
APCSET
MOD–
OUTPOL
MOD+
IBMAX
VCC
CAPC
BIAS
PD
18
17
16
15
14
13
1
2
3
4
5
6
GND
MONP
VCC
MONB
DIN+
SDOWN
DIN–
FLTMODE
VCC
MODSET
GND
MODTC
24 23 22 21 20 19
7 8 9 10 11 12
RGEPACKAGE
(TOP VIEW)
ONET4211LD
SLLS688A – NOVEMBER 2005 – REVISED SEPTEMBER 2007
Figure 3. Pinout of the ONET4211LD in a 4-mm × 4-mm, 24-Lead QFN Package (Top View)
TERMINAL FUNCTIONS
TERMINAL
TYPE DESCRIPTION
NAME NO.
APCSET 23 Analog-in Set photodiode reference current with resistor to GND.
BIAS 13 Analog-out Laser-diode bias-current sink. Connect to laser cathode.
CAPC 20 Analog APC loop capacitor
DIN+ 3 CML-in Non-inverted data input. On-chip, 50- Ω terminated to VCC.
DIN – 4 CML-in Inverted data input. On-chip, 50- Ω terminated to VCC.
DISABLE 24 LVTTL-in Disable modulation and bias-current outputs.
FLTMODE 10 CMOS-in Fault mode selection input. If a low level is applied to this pin, any fault event is latched and the
bias and modulation currents are disabled in a fault condition. Toggling of DISABLE or VCC
resets the fault condition. If pin is set to a high level, fault events are flagged at the SDOWN
output but not latched. The bias and modulation currents are not disabled. SDOWN is reset
once the fault condition disappears.
GND 1, 6, 18, EP Supply Circuit ground. The exposed die pad (EP) must be grounded.
IBMAX 21 Analog-in Set maximum laser diode current with resistor to GND.
MOD+ 15 Analog-out Laser modulation current output. Connect to laser cathode. Avoid usage of vias on board.
MOD – 16 Analog-out Complementary laser modulation current output. Connect to VCC adjacent to anode of laser
diode. Avoid usage of vias on board.
MODSET 11 Analog-in Set temperature-independent modulation current with resistor to GND.
MODTC 12 Analog-in Set modulation-current temperature compensation with resistor to GND.
MONB 8 Analog-out Bias current monitor. Sources 1/68 of the bias current.
MONP 7 Analog-out Photodiode current monitor. Sources a current identical to the photodiode current.
OUTPOL 22 LVTTL-in Alters modulation current output polarity. Open or high: normal polarity; low: inverted polarity.
OUTPOL is pulled up internally. Normal polarity: when DIN+ is high, current is sunk into MOD+.
PD 19 Analog-in Monitor photodiode input. Connect to photodiode anode for APC. Sinks the photodiode current
to GND.
SDOWN 9 LVTTL-out Fault detection flag
VCC 2, 5, 14, 17 Supply 3.3-V, ± 10% supply voltage
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Product Folder Link(s): ONET4211LD