ICS8533I-31
LOW SKEW, 1-TO-4, CRYSTAL OSCILLATOR/DIFFERENTIAL-TO- 3.3V LVPECL FANOUT BUFFER
PRELIMINARY
Table 1. Pin Descriptions
Number
Name
Type
Description
1
VEE
Power
Input
Negative supply pin.
Synchronizing clock enable. When HIGH, clock outputs follows clock input.
When LOW, Q outputs are forced low, nQ outputs are forced high. LVCMOS /
LVTTL interface levels.
2
CLK_EN
Pullup
Clock select input. When LOW, selects CLK, nCLK input.
When HIGH, selects XTAL input. LVCMOS / LVTTL interface levels.
3
CLK_SEL
Input
Pulldown
4
5
CLK
Input
Input
Pulldown Non-inverting differential clock input.
nCLK
Pullup
Inverting differential clock input.
6,
7
XTAL_IN
XTAL_OUT
Input
Crystal oscillator interface XTAL_IN is the input, XTAL_OUT is the output.
8, 9
10, 13, 18
11, 12
nc
Unused
Power
No connect.
VCC
Power supply pins.
nQ3, Q3
nQ2, Q2
nQ1, Q1
nQ0, Q0
Output
Output
Output
Output
Differential clock output pair. LVPECL interface levels.
Differential clock output pair. LVPECL interface levels.
Differential clock output pair. LVPECL interface levels.
Differential clock output pair. LVPECL interface levels.
14, 15
16, 17
19, 20
NOTE: Pullup refers to internal input resistors. See Table 2, Pin Characteristics, for typical values.
Table 2. Pin Characteristics
Symbol
CIN
Parameter
Test Conditions
Minimum
Typical
Maximum
Units
pF
Input Capacitance
Input Pullup Resistor
4
RPULLUP
51
51
kΩ
RPULLDOWN Input Pulldown Resistor
kΩ
IDT™ / ICS™ 3.3V LVPECL FANOUT BUFFER
2
ICS8533AGI-31 REV. A DECEMBER 13, 2007