ICS840002-01 Datasheet, PDF (2/12 Pages) Integrated Circuit Systems – FEMTOCLOCKS™ CRYSTAL-TO LVCMOS/LVTTL FREQUENCY SYNTHESIZER

Integrated
Circuit
Systems, Inc.
ICS840002-01
FEMTOCLOCKS™ CRYSTAL-TO-
LVCMOS/LVTTL FREQUENCY SYNTHESIZER
TABLE 1. PIN DESCRIPTIONS
Number
Name
Type
Description
1
F_SEL0
Input
Pullup Frequency select pin. LVCMOS/LVTTL interface levels.
Selects between the crystal or TEST_CLK inputs as the PLL reference
2
nXTAL_SEL Input Pulldown source. When HIGH, selects TEST_CLK. When LOW, selects XTAL
inputs. LVCMOS/LVTTL interface levels.
3
TEST_CLK
Input Pulldown Single-ended LVCMOS/LVTTL clock input.
4
5
6
7
8
9,
10
11
12, 13
OE
MR
nPLL_SEL
V_DDA
V_DD
XTAL_OUT,
XTAL_IN
V_DDO
Q1, Q0
Input
Input
Input
Power
Power
Input
Power
Output
Pullup
Pulldown
Pulldown
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
reset causing active outputs 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.
When HIGH, the PLL is bypassed and the output frequency =
reference clock frequency/N output divider.
LVCMOS/LVTTL interface levels.
Analog supply pin.
Core supply pin.
Crystal oscillator interface. XTAL_OUT is the output.
XTAL_IN is the input.
Output supply pin.
Single-ended clock outputs. LVCMOS/LVTTL interface levels.
14, 15
GND
Power
Power supply ground.
16
F_SEL1
Input
Pullup Frequency select pin. LVCMOS/LVTTL interface levels.
NOTE: Pullup and Pulldown refer to internal input resistors. See Table 2, Pin Characteristics, for typical values.
TABLE 2. PIN CHARACTERISTICS
Symbol
C
IN
C_PD
R_PULLUP
R_PULLDOWN
Parameter
Input Capacitance
Power Dissipation Capacitance
Input Pullup Resistor
Input Pulldown Resistor
R_OUT
Output Impedance
Test Conditions
3.3V±5%
2.5V±5%
Minimum
14
16
Typical
4
8
51
51
17
21
Maximum
21
25
Units
pF
pF
kΩ
kΩ
Ω
Ω
840002AG-01
www.icst.com/products/hiperclocks.html
2
REV. B JANUARY 13, 2006