vsc8169 Vitesse Semiconductor Corp, vsc8169 Datasheet - Page 6

• Manufacturer Part Number: vsc8169
• Description: Oc-48 Fec 16 1 Sonet/sdh Mux With Clock Generator
• Manufacturer: Vitesse Semiconductor Corp

Page 6
MUX with Clock Generator
OC-48 (FEC) 16:1 SONET/SDH
Supplies
to use the device in an ECL environment with a negative 3.3V supply, then V
-3.3V. If used with V
recommended that the V
on each V
also be placed in parallel with the 0.1 F and 0.01 F capacitors mentioned above. Recommended capacitors are
low-inductance ceramic SMT X7R devices. For the 0.1 F capacitor, a 0603 package should be used. The
0.01 F and 0.001 F capacitors can be either 0603 or 0402 packages.
maintain the optimal jitter and loop bandwidth characteristics of the PLL contained in the VSC8169, the analog
power supply pins should be filtered from the main power supply with a 10 H C-L-C pi filter. If preferred, a
ferrite bead may be used to provide the isolation. The 0.1 F and 0.01 F decoupling capacitors are still required
and must be connected to the supply pins between the device and the C-L-C pi filter (or ferrite bead).
main +3.3V power supply and placed close to the C-L-C pi filter.
V
CC
Extra care needs to be taken when decoupling the analog power supply pins (labeled V
For low frequency decoupling, 47 F tantalum low inductance SMT caps are sprinkled over the board’s
If the device is being used in an ECL environment with a -3.3V supply, then all references to decoupling
The VSC8169 is specified as a LVPECL device with a single positive 3.3V supply. Should the user desire
Decoupling of the power supplies is a critical element in maintaining the proper operation of the part. It is
must be changed to V
CC
power supply pin as close to the package as possible. If room permits, a 0.001 F capacitor should
EE
© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012
tied to -3.3V, the TTL control signals are still referenced to V
V
CC
CC
EE
Figure 8: PLL Power Supply Decoupling Scheme
power supply be decoupled using a 0.1 F and 0.01 F capacitor placed in parallel
Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]
, and all references to decoupling 3.3V must be changed to -3.3V.
10 F
VITESSE
SEMICONDUCTOR CORPORATION
0.1 F
V
EE
Internet: www.vitesse.com
10 H
V
0.1 F
EE_ANA
0.01 F
CC
Preliminary Data Sheet
will be ground and V
V
CC_ANA
EE
.
CCANA
VSC8169
). In order to
EE
G52230-0, Rev 3.6
will be
01/02/01