
ICS844004AKI-104 REVISION A DECEMBER 15, 2010
8
2010 Integrated Device Technology, Inc.
ICS844004I-104 Data Sheet
FEMTOCLOCK CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER
Parameter Measurement Information, continued
Differential Output Voltage Setup
Offset Voltage Setup
Applications Information
Power Supply Filtering Technique
As in any high speed analog circuitry, the power supply pins are
vulnerable to random noise. To achieve optimum jitter performance,
power supply isolation is required. The ICS844004I-104 provides
separate power supplies to isolate any high switching noise from the
outputs to the internal PLL. VDD, VDDA and VDDO should be
individually connected to the power supply plane through vias, and
0.01F bypass capacitors should be used for each pin. Figure 1
illustrates this for a generic VDD pin and also shows that VDDA
requires that an additional 10
resistor along with a 10F bypass
capacitor be connected to the VDDA pin.
Figure 1. Power Supply Filtering
100
out
LVDS
DC Input
VOD/ VOD
V
DD
out
LVDS
DC Input
VOS/ VOS
V
DD
VDD
VDDA
3.3V or 2.5V
10
10F
.01F