ICS MK2745-24

I C R O C LOC K
MK2745-24
DVD/MPEG Clock Source
Description
Features
The MK2745-24 is a low cost, low jitter, high
performance clock synthesizer for DVD and other
MPEG 2 based applications. Using analog PhaseLocked Loop (PLL) techniques, the device accepts
a 27.00 MHz fundamental mode crystal or clock
input to produce multiple audio output clocks, a
processor clock, and two 27 MHz clocks. The
audio clocks are frequency locked to the
27.00 MHz using our patented zero ppm error
techniques, allowing audio and video to track
exactly, thereby eliminating the need for large
buffer memory.
• Packaged in 16 pin narrow (150 mil) SOIC
• Ideal for AuraVision’s notebook DVD solutions
• Patented zero ppm audio clock error for exact
audio clock sampling rates, plus 32x and 256x
clocks of the sampling frequencies
• Selectable audio sampling frequencies support
32, 44.1, 48 and 96 kHz in most DACs
• 27.00 MHz fundamental crystal or clock input
• Selectable processor frequencies
• Two clocks of 27 MHz
• Zero ppm error in all clocks
• 25mA output drive capability at TTL levels
• Advanced, low power, sub-micron CMOS process
• 3.0V to 5.5V operating voltage
• See also the MK2712 for NTSC/PAL clocks
MicroClock manufactures the largest variety of
DVD, Set-Top Box, and multimedia clock
synthesizers for all applications. Consult
MicroClock to eliminate crystals and oscillators
from your board.
Block Diagram
ACS1:0
PCS
VDD
2
GND
3
Clock Synthesis
and Control
Circuitry
27 MHz clock
or crystal X1
Crystal
Oscillator
X2
Output
Buffer
PCLK
Output
Buffer
ACLK
÷8
Output
Buffer
ACLK/8
÷256
Output
Buffer
ACLK/256
Output
Buffer
27.0 MHz
Output
Buffer
27.0 MHz
/2
1
Revision 100898
Printed 11/16/00
MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
MDS 2745-24 B
MK2745-24
DVD/MPEG Clock Source
I C R O C LOC K
Pin Assignment
MK2745-24
GND
1
16
Audio Clocks Selection Table (in MHz)
ACS1
ACS1 ACS0
ACLK
ACLK/8
ACLK/256
0
24.576
3.072
96.0 kHz
X2
2
15
27M
0
0
1
11.2896
1.4112
44.1 kHz
X1/ICLK
3
14
PCLK
1
0
8.192
1.024
32.0 kHz
VDD
4
13
VDD
1
1
12.288
1.536
48.0 kHz
GND
5
12
GND
27M
6
11
ACLK
ACS0
7
10
ACLK/8
8
9
PCS
ACLK/256
16 pin (150 mil) SOIC
Processor Clock (MHz)
PCS
PCLK
0
40
1
60
0 = connect directly to ground
1 = connect directly to VDD
Pin Descriptions
Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Name
GND
X2
X1/ICLK
VDD
GND
27M
ACS0
ACLK/8
ACLK/256
PCS
ACLK
GND
VDD
PCLK
27M
ACS1
Type
P
XO
XI
P
P
O
I
O
O
I
O
P
P
O
O
I
Description
Connect to ground.
Crystal connection. Connect to 27 MHz crystal. Leave unconnected for clock input.
Crystal connection. Connect to 27 MHz crystal or connect to 27 MHz input clock.
Connect to +3.3 V or +5 V. Must be same as other VDD.
Connect to ground.
27.00 MHz clock output.
Audio Clock Select 0. Selects audio clocks per table above.
Audio Clock divided by 8 output. Determined by status of ACS1, ACS0. See table above.
Audio Clock divided by 256 output. Determined by status of ACS1, ACS0. See table above.
Processor Clock Select pin. Selects PCLK per table above.
Audio Clock output. Determined by status of ACS1, ACS0. See table above.
Connect to ground.
Connect to +3.3 V or +5 V. Must be same as other VDD.
Processor Clock output. Determined by status of PCS. See table above.
27.00 MHz clock output.
Audio Clock Select 1. Selects audio clocks per table above.
Key: I = Input, O = output, P = power supply connection
2
Revision 100898
Printed 11/16/00
MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
MDS 2745-24 B
I C R O C LOC K
MK2745-24
DVD/MPEG Clock Source
Electrical Specifications
Parameter
Conditions
Minimum
Typical
Maximum
Units
7
VDD+0.5
70
260
150
V
V
°C
°C
°C
5.5
V
V
V
V
V
V
V
V
mA
mA
pF
ABSOLUTE MAXIMUM RATINGS (note 1)
Supply voltage, VDD
Inputs and Clock Outputs
Ambient Operating Temperature
Soldering Temperature
Storage temperature
Referenced to GND
Referenced to GND
-0.5
0
Max of 20 seconds
-65
DC CHARACTERISTICS (VDD = 5.0V unless noted)
Operating Voltage, VDD
Input High Voltage, VIH, X1/ICLK pin only
Input Low Voltage, VIL, X1/ICLK pin only
Input High Voltage, VIH
Input Low Voltage, VIL
Output High Voltage, VOH
Output Low Voltage, VOL
Output High Voltage, VOH, CMOS level
Operating Supply Current, IDD
Short Circuit Current
Input Capacitance
3
VDD/2 + 1
VDD/2
VDD/2
VDD/2 - 1
2
0.8
IOH=-25mA
IOL=25mA
IOH=-8mA
No Load, note 2
Each output
2.4
0.4
VDD-0.4
37
±100
7
AC CHARACTERISTICS (VDD = 5.0V unless noted)
Input Frequency
Output Clock Rise Time
Output Clock Fall Time
Output Clock Duty Cycle
Frequency synthesis error, all clocks
Absolute Jitter, short term
Notes:
27.000
0.8 to 2.0V
2.0 to 0.8V
At VDD/2
Variation from mean
40
0
200
1.5
1.5
60
1
MHz
ns
ns
%
ppm
ps
1. Stresses beyond those listed under Absolute Maximum Ratings could cause permanent damage to the device. Prolonged
exposure to levels above the operating limits but below the Absolute Maximums may affect device reliability.
2. With VDD=3.3V, processor clock at 60MHz, and ACLK at 12.288MHz.
External Components
The MK2745-24 requires a minimum number of external components for proper operation. Decoupling
capacitors of 0.1µF should be connected between VDD and GND (on pins 4 and 5, and pins 13 and 12),
as close to the MK2745-24 as possible. A series termination resistor of 33Ω may be used for each clock
output. If a clock input is not used, the 27.00 MHz crystal must be connected as close to the chip as
possible. The crystal should be a fundamental mode (do not use third overtone), parallel resonant, 50ppm
or better. Crystal capacitors should be connected from pins X1 to ground and X2 to ground. The value of
these capacitors is given by the following equation, where CL is the crystal load capacitance: Crystal caps
(pF) = (CL -6) x 2. So for a crystal with 16pF load capacitance, two 20pF caps should be used.
3
Revision 100898
Printed 11/16/00
MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
MDS 2745-24 B
MK2745-24
DVD/MPEG Clock Source
I C R O C LOC K
Package Outline and Package Dimensions
E
Symbol
A
b
c
D
E
H
e
h
Q
H
Inches
Min
Max
0.055 0.070
0.013 0.019
0.007 0.010
0.385 0.400
0.150 0.160
0.225 0.245
.050 BSC
0.016
0.004
0.01
Millimeters
Min
Max
1.397
1.778
0.330
0.483
0.191
0.254
9.779 10.160
3.810
4.064
5.715
6.223
1.27 BSC
0.406
0.102
0.254
h x 45°
D
c
Q
e
16 pin SOIC narrow
A
b
Ordering Information
Part/Order Number
MK2745-24S
MK2745-24STR
Marking
MK2745-24S
MK2745-24S
Shipping packaging
tubes
tape and reel
Package
Temperature
16 pin narrow SOIC
0-70°C
16 pin narrow SOIC
0-70°C
Rev. 04218, version A . First publication, Preliminary.
Rev. 10088, version B. Production.
While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems, Incorporated (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.
4
Revision 100898
Printed 11/16/00
MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
MDS 2745-24 B