874001AGI-05LF Integrated Device Technology (Idt), 874001AGI-05LF Datasheet - Page 13

• Manufacturer Part Number: 874001AGI-05LF
• Description: PCI Express Jitter Attenuator 20-Pin TSSOP Tube
• Manufacturer: Integrated Device Technology (Idt)

Specifications of 874001AGI-05LF

• Package: 20TSSOP
• Operating Temperature: -40 to 85 °C

ICS74001I-05 Data Sheet
Schematic Layout
Figure 4 shows an example of ICS874001I-05 application schematic.
In this example, the device is operated at V
The input is driven by a 3.3V LVPECL driver.
As with any high speed analog circuitry, the power supply pins are
vulnerable to noise. To achieve optimum jitter performance, power
supply isolation is required. The ICS74001I-05 provides separate
power supplies to isolate from coupling into the internal PLL.
In order to achieve the best possible filtering, it is recommended that
the placement of the filter components be on the device side of the
PCB as close to the power pins as possible. If space is limited, the
0.1uF capacitor in each power pin filter should be placed on the
device side of the PCB and the other components can be placed on
the opposite side.
Figure 4. ICS874001I-05 Schematic Layout
ICS874001AGI-05 REVISION A JANUARY 14, 2011
Logic Control Input Examples
VDD
RU1
1K
RD1
Not Install
VDD
Set Logic
Input to
'1'
3.3V
To Logic
Input
pins
0.1uF
C6
1
10
Ferrite Bead
BLM18BB221SN1
R1
VDD
RU2
Not Install
RD2
1K
Set Logic
Input to
'0'
2
C2
10u
To Logic
Input
pins
C7
10uF
C3
0.1u
VDDA
VDD
LVPECL Driv er
VDD
DD
= V
PLL_SEL
MR
F_SEL1
F_SEL0
DDA
3.3V
C4
0.01u
Zo = 50 Ohm
Zo = 50 Ohm
0.1uF
C8
= V
1
10
1
2
3
4
5
6
7
8
9
U1
Ferrite Bead
BLM18BB221SN2
DDO
PLL_SEL
nc
nc
nc
MR
nc
F_SEL1
VDDA
F_SEL0
VDD
= 3.3V.
2
R4
50
C9
VDDO
13
nCLK
GND
CLK
R7
50
10uF
OE
nQ
nc
nc
nc
Power supply filter recommendations are a general guideline to be
used for reducing external noise from coupling into the devices. The
filter performance is designed for wide range of noise frequencies.
This low-pass filter starts to attenuate noise at approximately 10kHz.
If a specific frequency noise component is known, such as switching
power supply frequencies, it is recommended that component values
be adjusted and if required, additional filtering be added. Additionally,
good general design practices for power plane voltage stability
suggests adding bulk capacitances in the local area of all devices.
The schematic example focuses on functional connections and is not
configuration specific. Refer to the pin description and functional
tables in the datasheet to ensure the logic control inputs are properly
set.
Q
VDDO
R5
50
20
19
18
17
16
15
14
13
12
11
CLK
nCLK
nCLK
CLK
OE
nQ
Q
GND
C1
0.1u
Q
nQ
VDDO
Zo_Dif f = 100 Ohm
Alternate
LVDS
Termination
LVDS Termination
Zo_Dif f = 100 Ohm
©2011 Integrated Device Technology, Inc.
PCI EXPRESS™ JITTER ATTENUATOR
0.1uF
C5
R3
50
R6
50
R2
100
+
-
+
-