FOA2322A Datasheet, PDF (26/37 Pages) Infineon Technologies AG – 3.2 Gbi t /s Laser Driver IC for Telecom and Datacom Applications

FOA2322A
3
Pin Description
Pin Description
Table 6
Pin Definitions and Functions
Signal Name Function
D / DN
Differential Input
CLK / CLKN Differential Input
CSELN
Logic Input
Explanation
Differential data input. D corresponds to O and DN
to ON current output. With a high level at D and a
low level at DN modulation current is drawn by O
and ON is inactive. With a low level at D and a high
level at DN modulation current is drawn by ON and
O is inactive. Both inputs are prebiased to internal
V_BBD. The input termination is 100 Ω.
Differential clock input for input data latch. The
input termination is 100 Ω.
A low level at CSELN enables the data input latch
(clocked mode), a high level or an open input
disables the data input latch (nonclocked mode). It
has an internal pull-up-resistor of about 10 kΩ.
O / ON
Differential Current These output signals drive the modulation current
Output
switched by D / DN data inputs.
CMOD
Control
The modulation controller characteristic can be set
to an i-controller with an external capacitor at
CMOD to V_EE and the time constants are
adjustable in mode 2. Let open if mode 1 is used.
VMOD
CISM
CILM
HWA
Output
Control
Control
Logic Output
Base of the output current mirror 1:10. For normal
application it can be leave open if not used.
With an external capacitor at CISM to V_CC the
delay time for detection of a bad duty cycle data
input situation can be increased. If the input signal
monitor is not used CISM has to be pulled down by
25 kΩ resistor to V_EE.
With an external capacitor at CILM to V_CC the
delay time for detection of static data input situation
can be increased. If the peak detector is not used
CILM has to short to V_CC.
HWA is an open collector output (indicator output).
A low level is generated whenever a bad duty cycle
data input situation is detected by the input signal
monitor circuit or if the supply voltage is lower than
the V_CC reset. Let open if not used.
Preliminary Data Sheet
22
2001-05