DATASHEET
PLL AUDIO CLOCK SYNTHESIZER
Description
The MK2704 is a low cost, low jitter, high-performance PLL
clock synthesizer designed to replace oscillators and PLL
circuits in set-top box and multimedia systems. Using IDT’s
patented analog Phase Locked Loop (PLL) techniques, the
device uses a 27 MHz crystal or clock input to produce a
buffered reference clock and a selectable audio clock.
The audio clock is frequency locked to the 27 MHz clock,
assuring that the audio with zero ppm error and video will
track perfectly.
IDT manufactures the largest variety of Set-Top Box and
multimedia clock synthesizers for all applications. Consult
IDT to eliminate VCXOs, crystals and oscillators from your
board.
MK2704
Features
•
•
•
•
Packaged in 8-pin SOIC
Available in Pb-free packaging
Uses an inexpensive, fundamental crystal or clock
Selectable audio output clock of 16.9344 MHz, 18.432
MHz, or 36.864 MHz
kHz, and 96 kHz
•
Supports MPEG sampling rates of 384x, 44.1 kHz, 48
•
•
•
•
•
Patented zero ppm synthesis error in all clocks
All frequencies are frequency locked
25 mA output drive capability at TTL levels
Advanced, low power, sub-micron CMOS process
Operating voltage of 3.3 V or 5 V
NOTE: EOL for non-green parts to occur on 5/13/10
per PDN U-09-01
Block Diagram
VDD
S1:0 2
PLL Clock
Synthesis
and Control
Circuitry
Crystal
Oscillator
CLK
X1
27 MHz
crystal or
clock input
27M
X2
GND
Capacitors are required for crystal tuning
IDT™
PLL AUDIO CLOCK SYNTHESIZER
1
MK2704
REV D 122109
MK2704
PLL AUDIO CLOCK SYNTHESIZER
CLOCK SYNTHESIZER
Pin Assignment
X1
VDD
GND
27M
1
2
3
4
8
7
6
5
X2
S0
S1
CLK
A
UDIO
C
LOCK
O
UTPUT
S
ELECT
T
ABLE
S1
0
0
1
1
S0
0
1
0
1
CLK (MHz)
36.864
Test
16.9344
18.432
Key: 0 = Connect pin directly to ground
8-pin (150 mil) SOIC
1 = Connect pin directly to VDD
Pin Descriptions
Pin
Pin
Number Name
1
2
3
4
5
6
7
8
X1
VDD
GND
27M
CLK
S1
S0
X2
Pin
Type
XI
Power
Power
Output
Output
Input
Input
XO
Connect to +3.3 V or +5 V.
Connect to ground.
Pin Description
Crystal Connection. Connect to a 27 MHz fundamental crystal or clock.
27.00 MHz buffered reference clock output.
Audio clock output per table above.
Audio clock frequency select input #1. Determines CLK output per table
above. Internal pull-up resistor.
Audio clock frequency select input #0. Determines CLK output per table
above. Internal pull-up resistor.
Crystal connection to a 27 MHz crystal, or leave unconnected for clock
output.
External Components
Decoupling Capacitor
As with any high performance mixed-signal IC, the MK2704
must be isolated from system power supply noise to perform
optimally.
A decoupling capacitor of 0.01µF must be connected
between VDD and GND on pins 2 and 3. It must be
connected close to the MK2704 to minimize lead
inductance. No external power supply filtering is required for
the MK2704.
Series Termination Resistor
A 33Ω terminating resistor can be used next to the clock
outputs for trace lengths over one inch.
Crystal Load Capacitors
The total on-chip capacitance is approximately 16 pF. A
parallel resonant, fundamental mode, AT cut 27 MHz 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
IDT™
PLL AUDIO CLOCK SYNTHESIZER
2
MK2704
REV D 122109
MK2704
PLL AUDIO CLOCK SYNTHESIZER
CLOCK SYNTHESIZER
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
-16
pF)*2. In this equation, C
L
= crystal load capacitance in pF.
Example: For a crystal with an 18 pF load capacitance, each
crystal capacitor would be 4 pF [(18-16) x 2] = 4.
Absolute Maximum Ratings
Stresses above the ratings listed below can cause permanent damage to the MK2704. These ratings, which are
standard values for IDT 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
Supply Voltage, VDD
All Inputs and Outputs
Ambient Operating Temperature
Storage Temperature
Soldering Temperature
7V
Rating
-0.5 V to VDD+0.5 V
0 to +70° C
-65 to +150° C
260° C
Recommended Operation Conditions
Parameter
Ambient Operating Temperature
Power Supply Voltage (measured in respect to GND)
Min.
0
+3.13
Typ.
Max.
+70
+5.50
Units
°
C
V
DC Electrical Characteristics
VDD=3.3 V ±5%
, Ambient temperature 0 to +70° C, unless stated otherwise
Parameter
Operating Voltage
Input High Voltage
Input Low Voltage
Input High Voltage
Input Low Voltage
Output High Voltage
Output Low Voltage
Symbol
VDD
V
IH
V
IL
V
IH
V
IL
V
OH
V
OL
Conditions
X1 pin only
Note 1
X1 pin only
Note 1
S0, S1 pins
S0, S1 pins
I
OH
= -12 mA
I
OL
= 12 mA
Min.
3.13
Typ.
Max.
5.50
Units
V
V
V
V
(VDD/2)+1 VDD/2
VDD/2 (VDD/2)-1
2.0
0.8
2.4
0.4
V
V
V
IDT™
PLL AUDIO CLOCK SYNTHESIZER
3
MK2704
REV D 122109
MK2704
PLL AUDIO CLOCK SYNTHESIZER
CLOCK SYNTHESIZER
Parameter
Output High Voltage, CMOS level
Operating Supply Current
Symbol
V
OH
IDD
Conditions
I
OH
= -4 mA
No load
VDD = 3.3.V
No load
VDD = 5 V
Min.
VDD-0.4
Typ.
10
18
+50
5
20
Max.
Units
V
mA
mA
mA
pF
Ω
Short Circuit Current
Input Capacitance
Nominal Output Impedance
Frequency Synthesis Error
C
IN
CLK output
S0, S1 pins
All Clocks
0
ppm
Note 1: CMOS level input. Nominal trigger point is VDD/2 for 3.3 V or 5 V operation
AC Electrical Characteristics
VDD = 3.3 V ±5%,
Ambient Temperature 0 to +70° C, unless stated otherwise
Parameter
Input Crystal or Clock Frequency
Input Crystal Accuracy
Output Clock Rise Time
Output Clock Fall Time
Output Clock Duty Cycle
Maximum Absolute Jitter, short
Note 1: Measured with 15 pF load.
Symbol
F
IN
t
OR
t
OF
t
ja
Conditions
Min.
Typ.
27
Max.
±30
Units
MHz
ppm
ns
ns
%
ps
0.8 to 2.0 V, Note 1
2.0 to 8.0 V, Note 1
at VDD/2, Note 1
Deviation from mean
1.5
1.5
45
±225
55
Thermal Characteristics
Parameter
Thermal Resistance Junction to
Ambient
Symbol
θ
JA
θ
JA
θ
JA
θ
JC
Conditions
Still air
1 m/s air flow
3 m/s air flow
Min.
Typ.
150
140
120
40
Max. Units
°
C/W
°
C/W
°
C/W
°
C/W
Thermal Resistance Junction to Case
IDT™
PLL AUDIO CLOCK SYNTHESIZER
4
MK2704
REV D 122109
MK2704
PLL AUDIO CLOCK SYNTHESIZER
CLOCK SYNTHESIZER
Package Outline and Package Dimensions
(8-pin SOIC, 150 Mil. Narrow Body)
Package dimensions are kept current with JEDEC Publication No. 95
Millimeters
8
Inches
Min
Max
Symbol
Min
Max
E
INDEX
AREA
H
1 2
D
A
A1
B
C
D
E
e
H
h
L
α
1.35
1.75
0.10
0.25
0.33
0.51
0.19
0.25
4.80
5.00
3.80
4.00
1.27 BASIC
5.80
6.20
0.25
0.50
0.40
1.27
0
°
8
°
.0532
.0688
.0040
.0098
.013
.020
.0075
.0098
.1890
.1968
.1497
.1574
0.050 BASIC
.2284
.2440
.010
.020
.016
.050
0
°
8
°
A
A1
h x 45
C
-C-
e
B
SEATING
PLANE
L
.10 (.004)
C
Ordering Information
Part / Order Number
MK2704S*
MK2704STR*
MK2704SLF
MK2704SLFTR
Marking
2704S
2704S
2704SL
2704SL
Shipping packaging
Tubes
Tape and Reel
Tubes
Tape and Reel
Package
8-pin SOIC
8-pin SOIC
8-pin SOIC
8-pin SOIC
Temperature
0 to +70°
0 to +70°
0 to +70°
0 to +70°
C
C
C
C
*NOTE: EOL for non-green parts to occur on 5/13/10 per PDN U-09-01
While the information presented herein has been checked for both accuracy and reliability, Integrated Device Technology (IDT) 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 IDT. IDT reserves the right to change any circuitry or specifications without notice. IDT
does not authorize or warrant any IDT product for use in life support devices or critical medical instruments.
IDT™
PLL AUDIO CLOCK SYNTHESIZER
5
MK2704
REV D 122109
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