ICS840004I-01 Datasheet, PDF (2/10 Pages) Integrated Circuit Systems – FEMTOCLOCKS™ CRYSTAL-TO LVCMOS/LVTTL FREQUENCY SYNTHESIZER

Integrated
Circuit
Systems, Inc.
PRELIMINARY
ICS840004I-01
FEMTOCLOCKS™ CRYSTAL-TO-
LVCMOS/LVTTL FREQUENCY SYNTHESIZER
TABLE 1. PIN DESCRIPTIONS
Number
Name
Type
Description
1, 20
F_SEL0,
F_SEL1
Input Pullup Frequency select pin. LVCMOS/LVTTL interface levels.
2, 9
nc
Unused
No connect.
Selects between the crystal or TEST_CLK inputs as the PLL reference
3
nXTAL_SEL Input Pulldown source. When HIGH, selects TEST_CLK. When LOW, selects XTAL
inpus. LVCMOS/LVTTL interface levels.
4
TEST_CLK
Input Pulldown Single-ended LVCMOS/LVTTL clock input.
5
OE
Input
Pullup
Output enable pin. When HIGH, the outputs are active. When LOW, the
outputs are in a high impedance state. LVCMOS/LVTTL interface levels.
Active HIGH Master Reset. When logic HIGH, the internal dividers are
6
MR
Input Pulldown reset causing the otuputs to go low. When logic LOW, the internal
dividers and the outputs are enabled. LVCMOS/LVTTL interface levels.
PLL Bypass. When LOW, the output is driven from the VCO output.
7
nPLL_SEL
Input
Pulldown
When HIGH, the PLL is bypassed and the output frequency =
reference clock frequency/N output divider.
LVCMOS/LVTTL interface levels.
8
V_DDA
Power
10
V_DD
Power
11,
12
XTAL_OUT,
XTAL_IN
Input
Analog supply pin.
Core supply pin.
Crystal oscillator interface. XTAL_OUT is the output.
XTAL_IN is the input.
13, 19
GND
Power
Power supply ground.
14, 15
17, 18
Q3, Q2,
Q1, Q0
Output
Single-ended clock outputs. LVCMOS/LVTTL interface levels.
15Ω typical output impedence.
16
V_DDO
Power
Output supply pin.
NOTE: Pullup and Pulldown refer to internal input resistors. See Table 2, Pin Characteristics, for typical values.
TABLE 2. PIN CHARACTERISTICS
Symbol Parameter
C_IN
Input Capacitance
C_PD
Power Dissipation Capacitance
R_PULLUP
R_PULLDOWN
R_OUT
Input Pullup Resistor
Input Pulldown Resistor
Output Impedance
Test Conditions
V_DD, V_DDA, V_DDO = 3.465V
V_DD, V_DDA = 3.465V, V_DDO = 2.625V
V , V , V = 2.625V
DD DDA DDO
Minimum
Typical
4
TBD
TBD
TBD
51
51
15
Maximum
Units
pF
pF
pF
pF
kΩ
kΩ
Ω
840004AGI-01
www.icst.com/products/hiperclocks.html
2
REV. A JUNE 28, 2005