PT7C4512 Datasheet, PDF (2/5 Pages) Pericom Semiconductor Corporation – PLL Clock Multiplier

PT7C4511
PLL Clock Multiplier
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Block Diagram
S0
S1
X1/ICLK
X2
PLL Clock Synthesis
and
Control Circuit
Crystal
Oscillator
Output
Buffer
CLK
Output
Buffer
REF
V_CC
GND
External Components
Decoupling Capacitor
As with any high-performance mixed-signal IC, the
PT7C4512 must be isolated from system power supply
noise to perform optimally. A decoupling capacitor of
0.01μF or 0.1uF must be connected between VCC and
the GND. It must be connected close to the PT7C4512
to minimize lead inductance. No external power supply
filtering is required for the PT7C4512.
Series Termination Resistor
A 33Ω terminating resistor can be used next to the
CLK pin for trace lengths over one inch.
Crystal Load Capacitors
There is no on-chip capacitance build-in chip. A
parallel resonant, fundamental mode crystal should be
used. The device crystal connections should include
pads for small capacitors from X1 to ground and from
X2 to ground. These capacitors are used to adjust the
stray capacitance of the board to match the nominally
required crystal load capacitance. Because load
capacitance can only be increased in this trimming
process, it is important to keep stray capacitance to a
minimum by using very short PCB traces (and no vias)
between the crystal and device. Crystal capacitors, if
needed, must be connected from each of the pins X1
and X2 to ground. The value (in pF) of these crystal
caps should equal C_L*2. In this equation, C_L= crystal
load capacitance in pF. Example: For a crystal with a 15
pF load capacitance, each crystal capacitor would be
30pF.
Maximum Ratings
Note:
Stresses greater than those listed under MAXIMUM
StorageTemperature.....................................................................................- 65oC to +150oC _{RATINGS may cause permanent damage to the}
Ambient OperatingTemperature...................................................................-40oC to +85oC ^{device. This is a stress rating only and functional}
SupplyVoltage to Ground Potential(V_CC)...................................................- 0.3V to +7.0V ^{operation of the device at these or any other condi-}
Inputs(Referenced to GND).............................................-0.5V to V_CC +0.5V
Clock Output(Referenced to GND)................................-0.5V to V_CC +0.5V
Soldering Temperature(Max of 10 seconds).................... 260 ^oC (Max. 10s)
tions above those indicated in the operational sec-
tions of this specification is not implied. Exposure to
absolute maximum rating conditions for extended
periods may affect reliability.
Recommended Operating Conditions
Sym
Parameter
V_CC
Supply voltage
T_A
Operating temperature
Conditions
-
-
Min
Typ
Max Unit
3.0
-
5.5
V
-40
-
+85
°C
2014-08-0003
PT0152-7
08/14/14
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