oq2541bhp NXP Semiconductors, oq2541bhp Datasheet - Page 12

• Manufacturer Part Number: oq2541bhp
• Description: Oq2541bhp; Oq2541bu Sdh/sonet Data And Clock Recovery Unit Stm1/4/16 Oc3/12/48 Ge
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Table 4 Output selection in a positive supply voltage application
Table 5 LOS and LOCK indication in a positive supply voltage application
D
The reference frequency dividers and the STM mode
selectors still operate the same in a positive supply voltage
application. The only difference is that pins formerly
connected to ground should now be connected to
V
to V
damage the IC.
RF
All RF inputs, outputs and internal signals of the OQ2541B
are referenced to pins GND. In the positive supply voltage
application, this means that all RF signals are referenced
to V
for proper RF performance. The best performance is
obtained when the transmission line reference plane is
also decoupled to V
decoupling schemes should be taken into account. While
designing the printed-circuit board, bear in mind that the
V
While laying out the application, the return path is the most
important issue to be considered. It is always advised to
carefully examine the current carrying loops in the design.
Care should be taken that low ohmic and low inductance
2000 Sep 18
DCR loop
DCR all outputs
DCR normal
Bypass loop
Bypass all outputs
Bypass normal
LOS active
LOS inactive
LOCK active
LOCK inactive
CC
CC
IVIDER SETTINGS
SDH/SONET data and clock recovery unit
STM1/4/16 OC3/12/48 GE
INPUT AND OUTPUTS
EE
CC
(5 V). Pins connected to V
has become what was formerly ground.
. Therefore, a clean V
MODE
because connecting these pins to ground (0 V) will
SIGNAL
CC
V
V
V
V
. Careful design of V
CC
EE
CC
EE
(V
(V
(5 V)
(5 V)
ENL
CC
CC
CC
EE
rail is of utmost importance
3.3 V) V
3.3 V) V
should still be connected
loss of signal: BER > 5
no loss of signal: BER < 1
reference clock present and VCRO
inside 1000 ppm window
no reference clock present or VCRO
outside 1000 ppm window
V
V
V
V
LEVEL ON PIN
CC
EE
CC
CC
EE
CC
CC
(V
(V
(5 V)
(5 V)
(5 V)
(5 V)
ALLON
and good
CC
CC
DESCRIPTION
3.3 V) V
3.3 V) V
12
V
V
V
V
return paths are available for all frequencies (both of
interest and not of interest). These return paths should
preferably have an enclosed area as small as possible,
both horizontally and vertically (by means of through-holes
or vias). The position of a decoupling capacitor is very
important. A decoupling capacitor at an unfavourable
position could do more damage than completely omitting
the capacitor, while at the right location it might mean the
difference between mediocre results and the ultimate
achievement.
CC
CC
CC
EE
EE
EE
BYPASS
(V
(V
(V
(5 V)
(5 V)
(5 V)
10
CC
CC
CC
10
2
3.3 V)
3.3 V)
3.3 V)
3
OQ2541BHP; OQ2541BU
0 V (ground)
5 V (V
0 V (ground)
5 V (V
CLOOP AND
DLOOPQ,
CLOOPQ
DLOOP,
LEVEL
active
active
active
active
CC
CC
)
)
OUTPUT
Product specification
DOUT, DOUTQ,
COUT AND
COUTQ
active
active
active
active
HIGH
HIGH
LOW
LOW
TTL