ICS83904AGI-02LF IDT, Integrated Device Technology Inc, ICS83904AGI-02LF Datasheet - Page 11

• Manufacturer Part Number: ICS83904AGI-02LF
• Description: IC FANOUT BUFFER 1:4 16-TSSOP
• Manufacturer: IDT, Integrated Device Technology Inc
• Series: HiPerClockS™r
• Type: Fanout Buffer (Distribution), Multiplexerr

Specifications of ICS83904AGI-02LF

• Number Of Circuits: 1
• Ratio - Input:output: 3:4
• Differential - Input:output: No/No
• Input: LVCMOS, LVTTL, Crystal
• Output: LVCMOS, LVTTL
• Frequency - Max: 200MHz
• Voltage - Supply: 2.375 V ~ 3.465 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-TSSOP
• Frequency-max: 200MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 83904AGI-02LF

C
Figure 1 shows an example of ICS83904I-02 crystal interface
with a parallel resonant crystal. The frequency accuracy can be
fine tuned by adjusting the C1 and C2 values. For a parallel crystal
with loading capacitance CL = 18pF, we suggest C1 = 15pF and
C2 = 15pF to start with. These values may be slightly fine tuned
further to optimize the frequency accuracy for different board
LVCMOS
The XTAL_IN input can accept a single-ended LVCMOS signal
through an AC coupling capacitor. A general interface diagram is
shown in Figure 2. The XTAL_OUT pin can be left floating. The
input edge rate can be as slow as 10ns. For LVCMOS inputs, it is
recommended that the amplitude be reduced from full swing to
half swing in order to prevent signal interference with the power
rail and to reduce noise. This configuration requires that the output
IDT
RYSTAL
ICS83904I-02
LOW SKEW, 1-TO-4, CRYSTAL-TO-LVCMOS/LVTTL FANOUT BUFFER
™
/ ICS
™
I
LVCMOS/LVTTL FANOUT BUFFER
NPUT
TO
XTAL I
I
NTERFACE
NTERFACE
F
IGURE
2. G
VDD
Ro
ENERAL
A
18pF Parallel Cry stal
PPLICATION
D
X1
F
IGURE
IAGRAM FOR
C2
15p
Rs
Zo = Ro + Rs
1. Crystal Input Interface
C1
15p
Zo = 50
R1 (optional)
LVCMOS D
11
0
I
NFORMATION
layouts. Slightly increasing the C1 and C2 values will slightly reduce
the frequency. Slightly decreasing the C1 and C2 values will slightly
increase the frequency. For the oscillator circuit below, R1 can be
used, but is not required. For new designs, it is recommended
that R1 not be used.
impedance of the driver (Ro) plus the series resistance (Rs) equals
the transmission line impedance. In addition, matched termination
at the crystal input will attenuate the signal in half. This can be
done in one of two ways. First, R1 and R2 in parallel should equal
the transmission line impedance. For most 50
and R2 can be 100 . This can also be accomplished by removing
R1 and making R2 50 .
VDD
RIVER TO
XTAL_IN
XTAL_OUT
R1
R2
.1uf
XTAL I
XTAL_IN
XTAL_OUT
NPUT
ICS83904AGI-02 REV. A AUGUST 21, 2007
I
NTERFACE
applications, R1