ICS ICS9120M-46

ICS9120-46
Integrated
Circuit
Systems, Inc.
Modem and Audio Clock Generator
General Description
The ICS9120-46 is a high performance frequency generator
designed to support the clock requirements of communication
and audio interfaces. It offers the clock frequencies required
by 28.8 baud modem plus sound system. These frequencies
are synthesized from 14.7456 MHz reference oscillator whose
buffered output is available for the reference.
High accuracy, low-jitter PLLs meet the -96dB signal-tonoise ratios required by 16-bit audio systems. Fast output
clock edge rates minimize board induced jitter.
The on-chip XTAL oscillator accuracy is better than ±100ppm
for an AT cut, 18pF load crystal with initial accuracy of ppm
plus TC, aging and load variation of ±20ppm each assuming
33pF ±5% external load capacitors.
Features
•
•
•
•
•
•
•
•
Generates 49.92 MHz, 40.32 MHz and 14.7456 MHz
Single 14.7456 MHz crystal reference
49.92 MHz accuracy tracks 40.32 MHz reference
80ps one sigma jitter maintains 16-bit performance
Output rise/fall times less than 1.5ns
On-chip loop filter components
3.0-5.5V supply range
8-pin, 150-mil SOIC package
Applications
•
Specifically designed to support the high performance
requirements of communication and audio interfaces.
Block Diagram
9120-46 Rev B 052497P
ICS reserves the right to make changes in the device data identified in this
publication without further notice. ICS advises its customers to obtain the latest
version of all device data to verify that any information being relied upon by the
customer is current and accurate.
ICS9120-46
Pin Configuration
Functionality
The ICS9120-46 incorporates a crystal oscillator circuit designed
to provide 50% duty cycle over a range of operating conditions,
including the addition of external crystal load capacitors to pins
X1 and X2.
For the crystal oscillator, the crystal load capacitance must be
connected externally by adding a capacitor from each of the X1
and X2 pins to ground. A parallel resonant 14.7456 MHz crystal is
recommended.
Duty cycle is also maintained when using an external clock source
(connected to X1, X2 left unconnected) as long as the external
clock has good duty cycle.
8-Pin SOIC
Functionality
X1 (MHz)
14.7456
PD#
0
1
CLK1
(MHz)
Low
49.92
CLK2
(MHz)
Low
40.32
REF
(MHa)
Low
14.7456
Pin Descriptions for ICS9120-46
PIN
N UM BER
PIN
N AM E
T YPE
1
X1
Input
2
3
V DD
G ND
Pow er
Pow er
4
C LK1
O utput
5
PD #
O utput
6
C LK2
O utput
7
R EF
O utput
8
X2
O utput
D ESC RIPTIO N
Crystal or external clock source. H as feedback bias for crystal.
N om inally 14.7456<N> M H z input applied. (N o internal load cap;
m ust connect external load cap to ground for crystal oscillator.)
+Pow er supply input.
G round return for Pin 2.
49.92 M H z target output clock
(w ith nom inal 14.7456 M H z input).
Power-down input. A ll outputs shut off and driven to low output state
w hen this pin is at logic low level. H as pull-up.
40.32 M H z target output clock.
14.7456 M Hz reference clock buffered output
(w ith nom inal 14.7456 M H z input).
Crystal output drive (leave this pin unconnected when using an
external clock). (N o internal load cap; m ust connect external load cap
to ground for crystal oscillator).
2
ICS9120-46
Absolute Maximum Ratings
AVDD, VDD referenced to GND .......................................................................... 7V
Operating temperature under bias .................................................... 0 oC to +70oC
Storage temperature ..................................................................... -65oC to +150 oC
Voltage on I/O pins referenced to GND ...................... GND -0.5V to VDD +0.5V
Power dissipation ...................................................................................... 0.5 Watts
Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress
rating only and 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 may
affect product reliability.
Electrical Characteristics at 5 V
VDD = +4.5 to +5.5 V, T A = 0 to 70oC unless otherwise stated
PARAMETER
Input Low Voltage
Input High Voltage
Input Low Current
Input High Current
Output Low Voltage
Output High Voltage
Output Low Current
Output High Current
Supply Current
Supply Current Power-down
Pull-up Resistor Value
SYMBOL
VIL
VIH
I IL
IIH
VOL
VOH
IOL
IOH
IDD
IDDPD
Rpu
Rise Time
Fall Time
Rise Time
Fall Time
Tr
Tf*
Tr
Tf
Duty Cycle
Dt
Duty Cycle
Dt
Jitter, One Sigma
Tjis
Jitter, Absolute
Jitter, One Sigma
Jitter Absolute
Input Frequency Range
Output Frequency Range
Power-up Time
Crystal Input Capacitance
Tjab
Tjis
Tjab
Fi
Fo
Tpu
Cinx
DC Characteristics
TEST CONDITIONS
VIN=0V
VIN=VDD
IOL=+10mA
IOH=-30mA
VOL=0.8V
VOH=2.4V
Unloaded
Unloaded; Pin 5=0V
AC Characteristics
15pF load 0.8 to 2.0V
15pF load 2.0 to 0.8V
15pF load 20% to 80%
15pF load 80% to 20%
15pF load @ 50% of
VDD; Except REFCLK
15pF load @ 50% of
VDD; REFCLK only
For all frequencies
except REFCLK
For all frequencies
except REFCLK
REFCLK only
REFCLK only
0 to 40.3 MHz
X1 (Pin 1),X2 (Pin 8)
MIN
2.0
-18.0
2.4
25.0
-
TYP
-8.3
0.15
3.7
45.0
-53.0
27.0
500.0
400.0
MAX
0.8
5.0
0.4
-35.0
50.0
800.0
800.0
UNITS
V
V
µA
µA
V
V
mA
mA
mA
µA
k ohm
-
0.8
0.6
1.7
1.1
2.0
1.5
3.0
2.5
ns
ns
ns
ns
45.0
50.0
55.0
%
40.0
45.0
60.0
%
-
70.0
90.0
ps
300.0
-1.0
11.0
11.0
-
270
350.0
0.8
14.0
5.5
5
300.0
500.0
1.0
17.0
58.0
12.0
-
ps
ps
ns
MHz
MHz
ms
pF
*Parameter is guaranteed by design and characterization. Not 100% tested in production.
3
ICS9120-46
Electrical Characteristics at 3.3 V
VDD = +3.0 to +3.7V, TA = 0O C-70oC unless otherwise stated
PARAMETER
Input Low Voltage
Input High Voltage
Input Low Current
Input High Current
Output Low Voltage
Output High Voltage
Output Low Current
Output High Current
Supply Current
Supply Current Powerdown
Pull-up Resistor Value
SYMBOL
VIL
VIH
IIL
IIH
VOL
VOH
IOL
IOH
IDD
IDDPD
DC Characteristics
TEST CONDITIONS
VIN=0V
VIN=VDD
IOL=6.0mA
IOH=4.0mA
VOL=0.2VDD
VOH=0.7VDD
Unloaded
Unloaded; Pin 5=0V
Rpu
Rise Time
Fall Time
Rise Time
Fall Time
Tr
Tf*
Tr
Tf
Duty Cycle
Dt
Duty Cycle
Dt
Jitter, One Sigma
Tj1s
Jitter Absolute
Tjab
Jitter, One Sigma
Jitter, Absolute
Input Frequency Range
Output Frequency Range
Power-up Time
Crystal Input Capacitance
Tj1s
Tjab
Fi
Fo
Tpu
Cinx
AC Characteristics
15pF load 0.8 to 2.0V
15pF load 2.0 to 0.8V
15pF load 20% to 80%
15pF load 80% to 20%
15pF load @ 50% of
VDD; Except REFCLK
15pF load @ 50% of
VDD; REFCLK only
For all frequencies
except REFCLK
For all frequencies
except REFCLK
REFCLK only
REFCLK only
0 to 40.3 MHz
X1 (Pin 1), X2 (Pin 8)
MIN
TYP
0.7VDD
-8.0
-3.6
0.05VDD
0.85VDD 0.94VDD
15.0
24.0
-13.0
20.0
UNITS
V
V
µA
µA
V
V
mA
mA
mA
-
200.0
400.0
µA
-
620.0
900.0
k ohm
-
2.2
1.2
2.3
1.2
3.5
2.5
4.0
3.0
ns
ns
ns
ns
45.0
50.0
55.0
%
40.0
45.0
60.0
%
-
80.0
100.0
ps
-350.0
±300.0
350.0
ps
-1.0
11.0
14.0
-
380.0
0.8
14.745
5.5
5
500.0
1.0
15.0
51.0
12.0
-
ps
ns
MHz
MHz
ms
pF
*Parameter is guaranteed by design and characterization. Not 100% tested in production.
4
MAX
0.2VDD
5.0
1.1
-8.0
40.0
ICS9120-46
8 Pin SOIC Package
Ordering Information
ICS9120M-46
Example:
ICS XXXX M-PPP
Pattern Number(2 or 3 digit number for parts with ROM code patterns)
Package Type
M=SOIC
Device Type (consists of 3 or 4 digit numbers)
Prefix
ICS=Standard Device
5
ICS reserves the right to make changes in the device data identified in this
publication without further notice. ICS advises its customers to obtain the latest
version of all device data to verify that any information being relied upon by the
customer is current and accurate.