eliminate crystals and oscillators from your board.
MK2744
MPEG/Set-Top Clock Source
Features
• Packaged in 16 pin narrow (150 mil) SOIC
• Zero ppm audio clock error for 256X and 384X
• Selectable audio sampling frequencies support
32 kHz, 44.1 kHz, and 48 kHz in most DACs
• 27.00 MHz fundamental crystal or clock input
• Selectable processor frequencies
• Fixed clocks of 27, and 3.6864 or 33MHz
• Zero ppm error in 3.686 MHz clock
• 25mA output drive capability at TTL levels
• Advanced, low power, sub-micron CMOS process
• 5V±10% operating voltage
• See also the MK2712 for NTSC/PAL clocks
Block Diagram
VDD
GND
2
AS2:0
3
2
Output
Buffer
Audio Clock
3.6864MHz or
33.00 MHz
Processor Clock
PS2:0
27.00 MHz
clock or
crystal
X1
3
Clock Synthesis
and Control
Circuitry
Output
Buffer
Output
Buffer
X2
Clock
Buffer/
Crystal
Oscillator
Output
Buffer
27 MHz
1
Revision 9297
Printed 12/4/97
MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
MDS2744D
ICRO
C
LOCK
Pin Assignment
MK2744
PS2
X2
X1/ICLK
VDD
GND
ACLK
PCLK
AS2
MK2744
MPEG/Set-Top Clock Source
Audio Clock (in MHz)
Decoding Table
PS1
PS0
3.68M/33M
VDD
AS1
GND
27M
AS0
AS2 AS1 AS0
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
ACLK
12.288
11.2896
8.192
24.576
8.192
16.9344
18.432
11.2896
Processor Clock (in MHz)
MK2744-07, -08, -09, -10
Address \ Version
-07, -09
PS2 PS1 PS0 PCLK
0
0
0
16.67
0
0
1
27
0
1
0
33.33
0
1
1
40
1
0
0
16
1
0
1
40.5
1
1
0
25
1
1
1
20
-08, -10
PCLK
33.33
54
66.66
80
32
81
50
40
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
Pin 14 Clock MK2744
-07, -08
3.6864 MHz
-09,-10
33.00 MHz
16 pin (150 mil) SOIC
Pin Descriptions
Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Name
PS2
X2
X1/ICLK
VDD
GND
ACLK
PCLK
AS2
AS0
27M
GND
AS1
VDD
3.68M/33M
PS0
PS1
Type
I
O
I
P
P
O
O
I
I
O
P
NI
P
O
I
I
0 = connect directly to ground
1 = connect directly to VDD
Description
Processor clock Select 2. Selects processor clock on pin 7 per table above.
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 +5V.
Connect to ground.
Audio Clock output. Determined by status of AS2, AS1, AS0. See table above.
Processor Clock output. Determined by status of PS2, PS1, PS0. See table above.
Audio clock Select 2. Selects audio clock on pin 6 per table above.
Audio clock Select 0. Selects audio clock on pin 6 per table above.
27.00 MHz clock output.
Connect to ground.
Audio clock Select 1. Selects audio clock on pin 6 per table above.
Connect to +5V.
3.6864 MHz or 33.00 MHz clock output. See table above.
Processor clock Select 0. Selects processor clock on pin 7 per table above.
Processor clock Select 1. Selects processor clock on pin 7 per table above.
Key: I = Input, NI = Non-TTL compatible input, O = output, P = power supply connection
2
Revision 9297
Printed 12/4/97
MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
MDS2744D
ICRO
C
LOCK
Electrical Specifications
Parameter
Supply voltage, VDD
Inputs and Clock Outputs
Ambient Operating Temperature
Soldering Temperature
Storage temperature
Operating Voltage, VDD
Input High Voltage, VIH, X1/ICLK pin only
Input Low Voltage, VIL, X1/ICLK pin only
Input High Voltage, VIH, AS1 pin
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
Frequency error, ACLK and 3.6864MHz clocks
Frequency error, 24.576 MHz ACLK only
Input Frequency
Output Clock Rise Time
Output Clock Fall Time
Output Clock Duty Cycle
Absolute Jitter, short term
Notes:
Conditions
Referenced to GND
Referenced to GND
Max of 20 seconds
MK2744
MPEG/Set-Top Clock Source
Minimum
Typical
Maximum
7
VDD+0.5
70
260
150
5.5
2.5
2.5
1.5
Units
V
V
°C
°C
°C
V
V
V
V
V
V
V
V
V
mA
mA
pF
ppm
ppm
MHz
ns
ns
%
ps
ABSOLUTE MAXIMUM RATINGS (note 1)
-0.5
0
-65
4.5
3.5
Pin 12 only
VDD-0.5
2
0.8
IOH=-25mA
IOL=25mA
IOH=-8mA
No Load, note 2
Each output
note 3
40
27.000
0.8 to 2.0V
2.0 to 0.8V
At VDD/2
Variation from mean
1.5
1.5
60
200
2.4
0.4
VDD-0.4
37
±100
7
0
40
DC CHARACTERISTICS (VDD = 5.0V unless noted)
AC CHARACTERISTICS (VDD = 5.0V unless noted)
40
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 Processor clock at 50MHz, and ACLK at 16.93MHz.
3. The 24.576 MHz audio clock is not 0ppm accurate. It runs at 40ppm high.
External Components
The MK2744 requires a minimum number of external components for proper operation. Decoupling
capacitors of 0.1µF should be connected between VDD and GND, as close to the MK2744 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 (don’t 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 C
L
is the crystal load capacitance: Crystal caps (pF) = (C
L
-4) x 2. So for a crystal with 16pF load
capacitance, two 24pF caps should be used.
3
Revision 9297
Printed 12/4/97
MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
MDS2744D
ICRO
C
LOCK
Package Outline and Package Dimensions
MK2744
MPEG/Set-Top Clock Source
16 pin SOIC narrow
Symbol
A
b
c
D
E
H
e
h
Q
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
0.190
0.254
9.779 10.160
3.810
4.064
5.715
6.223
1.27 BSC
0.406
0.102
0.254
E
H
D
Q
e
b
c
h x 45°
A
Ordering Information
Part/Order Number
MK2744-0xS
MK2744-0xSTR
Marking
MK2744-0xS
MK2744-0xS
Shipping packaging
tubes
tape and reel
Package
16 pin SOIC
16 pin SOIC
Temperature
0-70°C
0-70°C
The -0x signifies the dash number or different version of the MK2744. For instance, if a processor clock of
16.667 MHz is required along with the 33 MHz fixed clock on pin 14, and parts are needed in tape and
reel, then the order should call for part number MK2744-09STR.
Rev. 3057, version C added fundamental mode to crystal specs on page 3. Deleted Preliminary.
While the information presented herein has been checked for both accuracy and reliability, MicroClock Incorporated 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 MicroClock. MicroClock reserves the right to change any circuitry or specifications without notice. MicroClock does not
authorize or warrant any MicroClock product for use in life support devices or critical medical instruments.
4
Revision 9297
Printed 12/4/97
MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
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