8421002I-01 Datasheet, PDF (1/15 Pages) Integrated Device Technology – FemtoClock Crystal-to-HSTL Frequency Synthesizer

FemtoClock^® Crystal-to-HSTL
Frequency Synthesizer
8421002I-01
DATA SHEET
GENERAL DESCRIPTION
The 8421002I-01 is a 2 output HSTL Synthesizer optimized to
generate Ethernet reference clock frequencies and is a member of
the HiPerClocks^TM family of high performance clock solutions from
IDT. Using a 25MHz, 18pF parallel resonant crystal, the following
frequencies can be generated based on the 2 frequency select pins
(F_SEL[1:0]): 156.25MHz, 125MHz and 62.5MHz. The 8421002I-01
uses IDT’s 3^rd generation low phase noise VCO technology and can
achieve 1ps or lower typical rms phase jitter, easily meeting Ethernet
jitter requirements. The 8421002I-01 is packaged in a small 20-pin
TSSOP package.
FEATURES
• Two HSTL outputs (VOHmax = 1.5V)
• Selectable crystal oscillator interface
or LVCMOS/LVTTL single-ended input
• Supports the following output frequencies: 156.25MHz,
125MHz, 62.5MHz
• VCO range: 560MHz - 680MHz
• RMS phase jitter @ 156.25MHz, using a 25MHz crystal
(1.875MHz - 20MHz): 0.44ps (typical)
• Power supply modes:
Core/Output
3.3V/1.8V
2.5V/1.8V
• -40°C to 85°C ambient operating temperature
• Available in lead-free (RoHS 6) compliant package
FREQUENCY SELECT FUNCTION TABLE
F_SEL1
0
0
1
1
F_SEL0
0
1
0
1
M Divider N Divider
Value
Value
25
4
25
5
25
10
not used
Output Frequency
(25MHz Ref.)
156.25
125
62.5
not used
BLOCK DIAGRAM
Pulldown
F_SEL[1:0]
Pulldown
nPLL_SEL
Pulldown
REF_CLK
1
25MHz
XTAL_IN
OSC
0
XTAL_OUT
Pulldown
nXTAL_SEL
Pulldown
MR
2
Phase
Detector
VCO
M = 25 (fixed)
F_SEL[1:0]
0 0 ÷4 (default)
1
0 1 ÷5
1 0 ÷10
1 1 Not Used
0
8421002I-01 REVISION B 8/14/15
1
PIN ASSIGNMENT
nc ₁
VDDO ₂
Q0 ₃
nQ0 ₄
MR ₅
nPLL_SEL ₆
nc ₇
VDDA ₈
F_SEL0 ₉
VDD ₁₀
20 ^VDDO
19 ^Q1
18 ^nQ1
17 ^GND
16 ^VDD
15 ^nXTAL_SEL
14 ^REF_CLK
13 ^XTAL_IN
12 ^XTAL_OUT
11 ^F_SEL1
8421002I-01
20-Lead TSSOP
6.5mm x 4.4mm x 0.92mm
package body
G Package
Top View
Q0
nQ0
Q1
nQ1
©2015 Integrated Device Technology, Inc.