STM1/4/16 Philips Semiconductors (Acquired by NXP), STM1/4/16 Datasheet - Page 8

• Manufacturer Part Number: STM1/4/16
• Description: Sdh/sonet Data And Clock Recovery Unit
• Manufacturer: Philips Semiconductors (Acquired by NXP)

Philips Semiconductors
1999 May 27
handbook, halfpage
handbook, full pagewidth
SDH/SONET data and clock recovery unit
STM1/4/16 OC3/12/48 GE
(1) L1 = RF choke type Murata BLM21 or equivalent.
Fig.7 Functionality of pin AREF.
500
16 k
on chip
Fig.6 Schematic diagram of OQ2541 power control loop.
V EE
GND
AREF
off chip
2
V AREF
R AREF
MGL667
1 k
100 nF
BAND GAP
REFERENCE
V EE
R1
2
> 100
1
k
8
PC
If the outputs are AC-coupled, the formulae for calculating
the required voltage on pin AREF and the value of the
resistor connected between pins AREF and V
follows:
and:
where R1 = 500 , R2 = 16 k and V
To maintain a single-ended swing of 200 mV (p-p) across
a 50
This can be achieved by connecting a 7.3 k resistor
between pins AREF and V
V
R
–
100 mV
AREF
AREF
3.3
nF
AC-coupled load, the voltage on pin AREF must be
=
=
1 F
GND
–
--------------------------------------------------------------- -
1
R
------------------- -
---------------------------------- -
L1
–
50 + 100
L
R1
R
(1)
+
R1
------- -
R2
L
50
R
o
on chip
off chip
MGL732
OQ2541HP; OQ2541U
---------------- - 1
V
4.5 V
V
0.5V
AREF
---------------- - 1
V
EE
V
AREF
EE
=
EE
swing
–
–
.
–
300 mV
Product specification
EE
= 3.3 V.
EE
as
(1)
(2)