ICS84025 Datasheet, PDF (1/12 Pages) Integrated Circuit Systems – CRYSTAL-TO-LVCMOS / LVTTL FREQUENCY SYNTHESIZER WITH FANOUT BUFFER

Integrated
Circuit
Systems, Inc.
PRELIMINARY
ICS84025
CRYSTAL-TO-LVCMOS / LVTTL
FREQUENCY SYNTHESIZER WITH FANOUT BUFFER
GENERAL DESCRIPTION
The ICS84025 is a Crystal-to-LVCMOS/LVTTL
,&6
Frequency Synthesizer with Fanout Buffer and
HiPerClockS™ _{a member of the HiPerClockS™ family of High}
Performance Clock Solutions from ICS. The
VCO frequency is programmed in steps equal
to the value of the crystal frequency. The VCO and
output frequency can be programmed using the feedback and
output frequency select pins. The low phase noise character-
istics of the ICS84025 make it an ideal clock source for Fibre
Channel 1 and Gigabit Ethernet applications.
FUNCTION TABLE
Inputs
XTAL Output Frequency
MR F_SEL1 F_SEL0
F_OUT
1
X
X
LOW
0
0
0
25.5MHz
53.125MHz
0
0
1 25.5MHz
106.25MHz
0
1
0
25MHz
62.5MHz
0
1
1
25MHz
125MHz
FEATURES
• 6 LVCMOS/LVTTL outputs
• Crystal oscillator interface
• Output frequency range: 53.125MHz to 125MHz
• Crystal input frequency: 25MHz and 25.5MHz
• RMS phase jitter at 106.25, using a 25.5MHz crystal
(637KHz to 10MHz): 3.25ps
• Phase noise:
Offset
Noise Power
100Hz ................. -100 dBc/Hz
1KHz ................. -115 dBc/Hz
10KHz ................. -125 dBc/Hz
100KHz ................. -127 dBc/Hz
• 3.3V core, outputs may either be 3.3V, 2.5V or 1.8V
• 0°C to 70°C ambient operating temperature
• Industrial temperature information available upon request
BLOCK DIAGRAM
PIN ASSIGNMENT
XTAL1
XTAL2
OSC
PLL
0
1
Output
Divider
/^{6 Q0:Q5}
Feedback
Divider
F_SEL1
PLL_SEL MR F_SEL0
VDDO 1
Q0 2
GND 3
Q1 4
VDDO 5
Q2 6
GND 7
Q3 8
VDDO 9
Q4 10
GND 11
Q5 12
24 F_SEL0
23 F_SEL1
22 MR
21 XTAL1
20 XTAL2
19 GND
1 8 VDDA
17 VDD
16 PLL_SEL
15 GND
14 nc
13 VDDO
ICS84025
24-Lead, 300-MIL SOIC
7.5mm x 15.33mm x 2.3mm body package
M Package
Top View
The Preliminary Information presented herein represents a product in prototyping or pre-production. The noted characteristics are based on initial
product characterization. Integrated Circuit Systems, Incorporated (ICS) reserves the right to change any circuitry or specifications without notice.
84025EM
www.icst.com/products/hiperclocks.html
REV. A APRIL 16, 2003
1