ICST ICS5OSK481 48 mhz tiny usb clock source Datasheet

P R E L I M I N A R Y I N F O R M AT I O N
ICS5OSK481
48 MHz Tiny USB Clock Source
Description
Features
The ICS5OSK481 is a low cost integrated clock
synthesizer solution designed for replacing crystals
and crystal oscillators.
• 25 MHz clock input
• The 48.00 MHz CLK output is USB2.0 reference
The ICS5OSK481 generates a very accurate 48.00
MHz clock output.
•
•
•
•
•
•
•
clock compliant
Output duty cycle 45/55% (worst case)
Advanced, low-power CMOS process
Industrial temperature range (-40 to +85°C)
Packaged in 5-pin TSOT
3.3 V supply voltage
Pb (lead) free package available
Short term C-C Jitter of 100 ps
Block Diagram
VDD
Clock
Buffer
ICLK
PLL
GND
OE
1
MDS 5OSK481 B
Integrated Circuit Systems, Inc.
CLK
●
525 Race Street, San Jose, CA 95126
Revision 111805
●
tel (408) 297-1201
●
www.icst.com
P R E L I M I N A R Y I N F O R M AT I O N
ICS5OSK481
48 MHz Tiny USB Clock Source
Pin Assignment
ICLK
1
GND
2
CLK
3
5
OE
4
VDD
Pin Descriptions
Pin
Number
Pin
Name
Pin
Type
1
ICLK
Input
25 MHz clock input. Connect to a parallel resonant fundamental crystal or
input clock.
2
GND
Power
Connect to ground.
3
CLK
Output
PLL output clock. Internal pull-down resistor.
4
VDD
Power
Connect to 3.3 V.
5
OE
Input
Output Enable pin. Internal pull-up resistor. OE=0 outputs tristate with weak
pull-down.
Pin Description
External Components
Decoupling Capacitor
to the VDD pin as possible. No vias should be used
between the decoupling capacitors and VDD pins. The
PCB trace to VDD pins should be kept as short as
possible, as should the PCB trace to the ground via.
As with any high-performance mixed-signal IC, the
ICS5OSK481 must be isolated from system power
supply noise to perform optimally.
A decoupling capacitor of 0.01µF must be connected
between each VDD and the PCB ground plane.
Series Termination Resistor
Clock output traces over one inch should use series
termination. To series terminate a 50Ω trace (a
commonly used trace impedance), place a 33Ω resistor
in series with the clock line, as close to the clock output
pin as possible. The nominal impedance of the clock
output is 20Ω.
2) To minimize EMI, the 33Ω series termination resistor
(if needed) should be placed close to the clock output.
3) An optimum layout is one with all components on the
same side of the board, minimizing vias through other
signal layers. Other signal traces should be routed
away from the ICS5OSK481. This includes signal
traces just underneath the device, or on layers adjacent
to the ground plane layer used by the device.
PCB Layout Recommendations
For optimum device performance and lowest output
phase noise, the following guidelines should be
observed.
1) The 0.01µF decoupling capacitors should be
mounted on the component side of the board as close
2
MDS 5OSK481 B
Integrated Circuit Systems, Inc.
●
525 Race Street, San Jose, CA 95126
Revision 111805
●
tel (408) 297-1201
●
www.icst.com
P R E L I M I N A R Y I N F O R M AT I O N
ICS5OSK481
48 MHz Tiny USB Clock Source
Absolute Maximum Ratings
Stresses above the ratings listed below can cause permanent damage to the ICS5OSK481. These ratings,
which are standard values for ICS commercially rated parts, are stress ratings only. Functional operation of
the device at these or any other conditions above those indicated in the operational sections of the
specifications is not implied. Exposure to absolute maximum rating conditions for extended periods can
affect product reliability. Electrical parameters are guaranteed only over the recommended operating
temperature range.
Item
Rating
Supply Voltage, VDD
7V
All Inputs and Outputs
-0.5 V to VDD+0.5 V
Ambient Operating Temperature
-40 to +85°C
Storage Temperature
-65 to +150°C
Soldering Temperature
260°C
Recommended Operation Conditions
Parameter
Min.
Ambient Operating Temperature
Power Supply Voltage (measured in respect to GND)
Typ.
Max.
Units
-40
+85
°C
+3.135
+3.465
V
DC Electrical Characteristics
Unless stated otherwise, VDD=3.3 V ±5% , Ambient temperature -40 to +85°C, CL=15 pF
Parameter
Symbol
Operating Voltage
Conditions
Min.
VDD
Typ.
3.135
Input High Voltage, ICLK only
VIH
ICLK
Input Low Voltage, ICLK only
VIL
ICLK
Input High Voltage
VIH
OE
Input Low Voltage
VIL
OE
Output High Voltage
VOH
IOH = -12 mA
Output Low Voltage
VOL
IOL = 12 mA
Max.
Units
3.465
V
(VDD/2)+1
V
(VDD/2)-1
2.0
V
V
0.8
2.4
V
V
0.4
V
IDD Operating Supply Current
No load
TBD
mA
Short Circuit Current
CLK output
+70
mA
On-Chip Pull-up Resistor
OE
270
kΩ
Input Capacitance, S1, S0, and OE
4
pF
Nominal Output Impedance
20
Ω
3
MDS 5OSK481 B
Integrated Circuit Systems, Inc.
●
525 Race Street, San Jose, CA 95126
Revision 111805
●
tel (408) 297-1201
●
www.icst.com
P R E L I M I N A R Y I N F O R M AT I O N
ICS5OSK481
48 MHz Tiny USB Clock Source
AC Electrical Characteristics
Unless stated otherwise, VDD=3.3 V ±5% , Ambient temperature -40 to +85°C, CL=15 pF
Parameter
Symbol
Input Frequency, clock input
Output Frequency, VDD = 3.3 V ±5%
Conditions
Min.
Typ.
0.5
25
MHz
-40°C to +85°C
48
MHz
FIN
FOUT
Max.
Units
Output Clock Rise Time
tOR
0.8 to 2.0 V, Note 1
1
ns
Output Clock Fall Time
tOF
2.0 to 8.0 V, Note 1
1
ns
Output Clock Duty Cycle
tOD
1.5 V
45
49-51
55
%
Output Enable Time, OE high to
output on
50
ns
Output Disable Time, OE low to
tri-state
50
ns
TBD
ps
Absolute Clock Period Jitter
tja
Deviation from
mean, Note 1
Note 1: Measured with 15 pF load.
4
MDS 5OSK481 B
Integrated Circuit Systems, Inc.
●
525 Race Street, San Jose, CA 95126
Revision 111805
●
tel (408) 297-1201
●
www.icst.com
P R E L I M I N A R Y I N F O R M AT I O N
ICS5OSK481
48 MHz Tiny USB Clock Source
Package Outline and Package Dimensions (5-pin TSOT)
Package dimensions are kept current with JEDEC Publication No. 95
Symbol
A
A1
A2
b
c
D
E
E1
e
e1
L
L1
L2
θ
aaa
Millimeters
Min
Max
—
1.00
0.01
0.10
0.84
0.90
0.30
0.45
0.12
0.20
2.90 BASIC
2.80 BASIC
1.60 BASIC
0.95 BASIC
1.90 BASIC
0.30
0.50
0.60 REF
0.25 BASIC
0°
8°
—
0.10
Ordering Information
Part / Order Number
Marking
Shipping Packaging
Package
Temperature
ICS5OSK481TILF
TBD
Tubes
5-pin TSOT
-40 to +85° C
ICS5OSK481TILFT
TBD
Tape and Reel
5-pin TSOT
-40 to +85° C
Parts that are ordered with a “LF” suffix to the part number are the Pb-Free configuration and are RoHS compliant.
While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems (ICS)
assumes no responsibility for either its use or for the infringement of any patents or other rights of third parties, which would
result from its use. No other circuits, patents, or licenses are implied. This product is intended for use in normal commercial
applications. Any other applications such as those requiring extended temperature range, high reliability, or other extraordinary
environmental requirements are not recommended without additional processing by ICS. ICS reserves the right to change any
circuitry or specifications without notice. ICS does not authorize or warrant any ICS product for use in life support devices or
critical medical instruments.
5
MDS 5OSK481 B
Integrated Circuit Systems, Inc.
●
525 Race Street, San Jose, CA 95126
Revision 111805
●
tel (408) 297-1201
●
www.icst.com
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