
ICS87946AYI REVISION B JUNE 22, 2012
2
2012 Integrated Device Technology, Inc.
ICS87946I Data Sheet
LOW SKEW, ÷1, ÷2 LVCMOS/LVTTL CLOCK GENERATOR
Table 1. Pin Descriptions
NOTE: Pullup and Pulldown refer to internal input resistors. See Table 2, Pin Characteristics, for typical values.
Table 2. Pin Characteristics
NOTE 1: VDDx denotes VDDA, VDDB, VDDC.
Number
Name
Type
Description
1
CLK_SEL
Input
Pulldown
Clock select input. When HIGH, selects CLK1. When LOW, selects CLK0.
LVCMOS / LVTTL interface levels.
2VDD
Power
Positive supply pin.
3, 4
CLK0, CLK1
Input
Pullup
LVCMOS/LVTTL clock inputs.
5
DIV_SELA
Input
Pulldown
Controls frequency division for Bank A outputs.
LVCMOS/LVTTL interface levels.
6
DIV_SELB
Input
Pulldown
Controls frequency division for Bank B outputs.
LVCMOS/LVTTL interface levels.
7
DIV_SELC
Input
Pulldown
Controls frequency division for Bank C outputs.
LVCMOS/LVTTL interface levels.
8, 11, 15, 20,
24, 27, 31
GND
Power
Power supply ground.
9, 13, 17
VDDC
Power
Positive supply pins for Bank C outputs.
10, 12,
14, 16
QC0, QC1,
QC2, QC3
Output
Bank C clock outputs. LVCMOS/LVTTL interface levels.
7
typical output impedance.
18, 22
VDDB
Power
Positive supply pins for Bank B outputs.
19, 21, 23
QB2, QB1, QB0
Output
Bank B clock outputs. LVCMOS/LVTTL interface levels.
7
typical output impedance.
25, 29
VDDA
Power
Positive supply pins for Bank A outputs.
26, 28, 30
QA2, QA1, QA0
Output
Bank A clock outputs. LVCMOS/LVTTL interface levels.
7
typical output impedance.
32
MR/nOE
Input
Pulldown
Master reset and output enable. When LOW, output drivers are enabled.
When HIGH, output drivers are in High-Impedance and dividers are reset.
LVCMOS / LVTTL interface levels.
Symbol
Parameter
Test Conditions
Minimum
Typical
Maximum
Units
CIN
Input Capacitance
4pF
RPULLUP
Input Pullup Resistor
51
k
RPULLDOWN Input Pulldown Resistor
51
k
CPD
Power Dissipation Capacitance
(per output); NOTE 1
VDD, VDDX = 3.6V
25
pF
ROUT
Output Impedance
7