IDT M685

Preliminary Information
M685
DUAL SAW, SELECTABLE FREQUENCY VCSO
FEATURES
◆ Two integrated SAW devices and selectable output
frequency; supports multi-rate optical interfaces
FOUT
4
nFOU
5
6
M685
M680
3
GND
2
F_SEL
(Top View)
1
The M685 is a dual SAW, selectable frequency VCSO
frequency source for low-jitter clock
generation. An integrated SAW (surface
acoustic wave) delay line implements the
high-Q VCO (voltage controlled oscillator)
function, which results in low output phase
noise and very low jitter. The M685-01 is available in
a range of center frequencies from 125 to 177 MHz.
The M685-02 provides 500 to 708 MHz. Guaranteed
minimum pull-range of ±120 ppm meets GbE
requirements. (It also fully satisfies ±50 ppm minimum
pull-range specification commonly required.) Industrystandard Kvco (VCO Gain) provides full replacement
compatibility. The M685 is well suited for phase-locked
loop implementations, clock and data recovery circuits,
and other timing applications in telecom and optical
fiber networking systems (e.g., OC-48).
VCC
PIN ASSIGNMENT (5 x 7.5mm SMT)
VIN
GENERAL DESCRIPTION
Figure 1: Pin Assignment
Sample of Available Output Frequencies
VCSO Center
Frequencies1 (MHz)
Applications
155.5200, 167.3316
SONET/SDH, SONET/SDH FEC
◆ M685-01 output frequencies from 125 to 177 MHz
M685-02 output frequencies from 500 to 708 MHz
(Specify center frequencies at time of order)
156.2500, 161.1328
Gigabit Ethernet, GbE FEC
622.0800, 669.3266
SONET/SDH, SONET/SDH FEC
◆ Industry-standard Kvco for full compatibility
625.0000, 644.5313
Gigabit Ethernet, GbE FEC
◆ Low phase jitter 0.2ps rms typical for the M685-02
(50kHz to 80MHz)
Table 1: Sample of Available Output Frequencies
Note 1: Specify VCSO center frequencies at time of order
◆ Differential 3.3V LVPECL output
◆ Single 3.3V power supply
◆ Small 5 x 7.5mm SMT (surface mount) package
◆ Pb-free / Compliant to EC RoHS Directive
BLOCK DIAGRAM
M685
SAW Delay Line
VCSO
Phase
Shifter
FOUT
VIN
SAW Delay Line
VCSO
nFOUT
Phase
Shifter
F_SEL
Figure 2: Block Diagram
M685 Datasheet Rev 0.7
Revised 29Jul2009
M685 Dual SAW, Selectable Frequency VCSO
I n t e g r a t e d D e v i c e Te c h n o l o g y, I n c . ● C o m m u n i c a t i o n M o d u l e s ● w w w. i d t . c o m ● t e l ( 5 0 8 ) 8 5 2 - 5 4 0 0
M685
DUAL SAW, SELECTABLE FREQUENCY VCSO
Preliminary Information
PIN DESCRIPTIONS
Name
VIN
I/O
F_SEL
Input
3
GND
Ground
4
5
6
FOUT
nFOUT
VCC
Number
1
2
Configuration
Description
Input
Output
Internal pull-down resistor1
Frequency control input.
Frequency select:
Logic 1 selects Frequency 2.
Logic 0 selects Frequency 1.
Power supply ground connection.
No internal terminator
Power
Clock output pair. Differential LVPECL.
Power supply connection, connect to +3.3V.
Table 2: Pin Descriptions
Note 1: See “Frequency Select” in Table 5 (DC Characteristics for M685-01 on pg. 3) and Table 7 (DC Characteristics for M685-02 on pg. 4).
ABSOLUTE MAXIMUM RATINGS1
Symbol Parameter
Rating
Unit
VI
Inputs
-0.5 to VCC +0.5
V
VO
Outputs
-0.5 to VCC +0.5
V
VCC
Power Supply Voltage
4.6
V
TS
Storage Temperature
-55 to +125
oC
Table 3: Absolute Maximum Ratings
Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the
device. These ratings are stress specifications only. Functional operation of product at these conditions
or any conditions beyond those listed in Recommended Conditions of Operation, DC Characteristics, or
AC Characteristics is not implied. Exposure to absolute maximum rating conditions for extended periods
may affect product reliability.
RECOMMENDED CONDITIONS OF OPERATION
Symbol Parameter
VCC
TA
Positive Supply Voltage
Min
Typ
Max
2.97
3.3
3.63
-40
Ambient Operating Temperature
25
+85
Unit
V
oC
Table 4: Recommended Conditions of Operation
M685 Datasheet Rev 0.7
2 of 7
Revised 29Jul2009
I n t e g r a t e d D e v i c e Te c h n o l o g y, I n c . ● C o m m u n i c a t i o n M o d u l e s ● w w w. i d t . c o m ● t e l ( 5 0 8 ) 8 5 2 - 5 4 0 0
M685
DUAL SAW, SELECTABLE FREQUENCY VCSO
Preliminary Information
ELECTRICAL SPECIFICATIONS FOR M685-01
DC Characteristics for M685-01
Unless stated otherwise, VCC = 3.3 Volts + 10%, TA = 0 to 85 oC, VCSO Freq.’s = 155.52, 167.3316MHz, Outputs terminated into 180Ω to ground
Symbol Parameter
Power Supply VCC
Pin
Positive Supply Voltage
VCC
Min
Typ
Max
Unit
2.97
3.3
3.63
V
90
125
mA
3.3
V
ICC
Power Supply Current
Control
Voltage
VIN
Input Control Voltage Range
Frequency
Select1
VIH
Input High Voltage
2
Vcc + 0.3
V
VIL
Input Low Voltage
-0.3
0.8
V
IIH
Input High Current
IIL
Input Low Current
0
VIN
VIN Input Impedence
5
F_SEL
kΩ
51
VOH
Output High Voltage
VOL
Output Low Voltage
VP-P
Peak to Peak Output Voltage2
Vcc - 0.98
IOUT
Output Current
FOUT, nFOUT
Vcc - 0.75 V
Vcc - 1.95
0.450
µA
µA
-150
Rpulldown Internal Pull-down Resistor
Differential
Outputs
kΩ
100
Vcc - 1.63 V
0.625
0.85
V P- P
20
mA
Table 5: DC Characteristics for M685-01
Note 1: Internally pulled down to Logic 0 (Frequency 1) if left unselected.
Note 2: Single-ended measurement. See Figure 3, Output Rise and Fall Time, on pg. 5.
AC Characteristics for M685-01
Unless stated otherwise, VCC = 3.3 Volts + 10%, TA = 0 to 85 oC, VCSO Freq.’s = 155.52, 167.3316MHz, Outputs terminated into 180Ω to ground
Symbol Parameter
Min
Control Voltage VIN
Modulation Bandwidth
Output
Output Center Frequency Range M685-01
FOUT
VIN
APR
Absolute (Guaranteed) Pull-Range
fSTAB
Frequency Stability
LIN
Tuning Linearity
KVCO
VCO Gain
Max
1
125
177
Jitter (rms)
@155.52MHz
odc
Output Duty Cycle 2
MHz
ppm p-p At any givin VIN
100
%
VIN = 0.3 to 3.0V
Best fit straight line
400
ppm/V VIN = 0.3 to 3.0V
-77
dBc
100Hz Offset
-48
55
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
ps rms
ps rms
%
@155.52MHz
J(t)
Notes
ppm
±120
6
SSB (single sideband)
Phase Noise, offset
from carrier
@155.52MHz
Unit
kHz
600
Non-harmonic Spurious
Φn
Typ
-50
1kHz Offset
-75
10kHz Offset
-99
100kHz Offset
-124
1MHz Offset
-142
12kHz to 20MHz
0.30
50kHz to 80MHz
0.18
45
2
tR
Output Rise Time for FOUT, nFOUT
275
425
ps
20% to 80%
tF
Output Fall Time 2 for FOUT, nFOUT
275
425
ps
20% to 80%
Note 1: Also fully meets ±50 ppm minimum pull-range specification that is commonly required.
Note 2: See Parameter Measurement Information on pg. 5.
M685 Datasheet Rev 0.7
3 of 7
Table 6: AC Characteristics for M685-01
Revised 29Jul2009
I n t e g r a t e d D e v i c e Te c h n o l o g y, I n c . ● C o m m u n i c a t i o n M o d u l e s ● w w w. i d t . c o m ● t e l ( 5 0 8 ) 8 5 2 - 5 4 0 0
M685
DUAL SAW, SELECTABLE FREQUENCY VCSO
Preliminary Information
ELECTRICAL SPECIFICATIONS FOR M685-02
DC Characteristics for M685-02
Unless stated otherwise, VCC = 3.3 Volts + 10%, TA = 0 to 85 oC, VCSO Freq.’s = 622.08, 669.3266MHz, Outputs terminated into 180Ω to ground
Symbol Parameter
Power Supply VCC
Pin
Positive Supply Voltage
VCC
Min
Typ
Max
Unit
2.97
3.3
3.63
V
90
125
mA
3.3
V
ICC
Power Supply Current
Control
Voltage
VIN
Input Control Voltage Range
Frequency
Select1
VIH
Input High Voltage
2
Vcc + 0.3
V
VIL
Input Low Voltage
-0.3
0.8
V
IIH
Input High Current
IIL
Input Low Current
0
VIN
VIN Input Impedence
5
F_SEL
kΩ
51
VOH
Output High Voltage
VOL
Output Low Voltage
VP-P
Peak to Peak Output Voltage2
Vcc - 0.98
IOUT
Output Current
FOUT, nFOUT
Vcc - 0.75 V
Vcc - 1.95
0.450
µA
µA
-150
Rpulldown Internal Pull-down Resistor
Differential
Outputs
kΩ
100
Vcc - 1.63 V
0.625
0.85
VP-P
20
mA
Table 7: DC Characteristics for M685-02
Note 1: Internally pulled down to Logic 0 (Frequency 1) if left unselected.
Note 2: Single-ended measurement. See Figure 3, Output Rise and Fall Time, on pg. 5.
AC Characteristics for M685-02
Unless stated otherwise, VCC = 3.3 Volts + 10%, TA = 0 to 85 oC, VCSO Freq.’s = 622.08, 669.3266MHz, Outputs terminated into 180Ω to ground
Symbol Parameter
Min
Control Voltage VIN
Modulation Bandwidth
Output
Output Center Frequency Range M685-02
FOUT
VIN
APR
Absolute (Guaranteed) Pull-Range
fSTAB
Frequency Stability
LIN
Tuning Linearity
KVCO
VCO Gain
Max
1
500
708
%
6
SSB (single sideband)
Phase Noise, offset
from carrier
@622.08MHz
J(t)
Jitter (rms)
@622.08MHz
odc
Output Duty Cycle 2
100Hz Offset
ppm/V VIN = 0.3 to 3.0V
-77
dBc
-42
55
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
ps rms
ps rms
%
1kHz Offset
-72
-102
100kHz Offset
-127
1MHz Offset
-146
0.22
50kHz to 80MHz
0.16
45
2
VIN = 0.3 to 3.0V
Best fit straight line
400
10kHz Offset
12kHz to 20MHz
MHz
ppm p-p At any givin VIN
100
-50
Notes
ppm
±120
@622.08MHz
Unit
kHz
600
Non-harmonic Spurious
Φn
Typ
tR
Output Rise Time for FOUT, nFOUT
275
400
ps
20% to 80%
tF
Output Fall Time 2 for FOUT, nFOUT
275
400
ps
20% to 80%
Note 1: Also fully meets ±50 ppm minimum pull-range specification that is commonly required.
Note 2: See Parameter Measurement Information on pg. 5.
M685 Datasheet Rev 0.7
4 of 7
Table 8: AC Characteristics for M685-02
Revised 29Jul2009
I n t e g r a t e d D e v i c e Te c h n o l o g y, I n c . ● C o m m u n i c a t i o n M o d u l e s ● w w w. i d t . c o m ● t e l ( 5 0 8 ) 8 5 2 - 5 4 0 0
M685
DUAL SAW, SELECTABLE FREQUENCY VCSO
Preliminary Information
PARAMETER MEASUREMENT INFORMATION
Output Rise and Fall Time
Output Duty Cycle
nFOUT
80%
80%
VP-P
Clock
Outputs
20%
tF
20%
tR
FOUT
tPW
(Output Pulse Width)
tPERIOD
Figure 3: Output Rise and Fall Time
odc =
tPW
tPERIOD
Figure 4: Output Duty Cycle
DEVICE PACKAGE - 5 x 7.5mm SMT (Surface Mount) Package
Mechanical Dimensions:
M685
-02-AA-AH
Dimensions are in mm;
dimensions in [ ] are in inches
Unless otherwise specified, all
dimensions are ±0.13 [0.005]
Figure 5: Device Package - 5 x 7.5mm SMT (Surface Mount) Package
M685 Datasheet Rev 0.7
5 of 7
Revised 29Jul2009
I n t e g r a t e d D e v i c e Te c h n o l o g y, I n c . ● C o m m u n i c a t i o n M o d u l e s ● w w w. i d t . c o m ● t e l ( 5 0 8 ) 8 5 2 - 5 4 0 0
M685
Preliminary Information
DUAL SAW, SELECTABLE FREQUENCY VCSO
ORDERING INFORMATION
M685-01 Standard Output Frequencies & Order Codes
Part Numbering Scheme
M685
M680-01
-0y - xx -xx
Part Number:
Device Number
Variant
-01 = Output Frequencies 125 - 177 MHz
-02 = Output Frequencies 500 - 708 MHz
Output Frequency 1 Order Code
Output Frequency 2 Order Code
See Tables 10 and 11 at right for frequency order codes.
Consult ICS for other frequencies and order codes.
Figure 6: Part Numbering Scheme
Example Order Numbers
For Output Frequencies (MHz)
Frequency 1, Frequency 2
155.5200, 167.3316
Order Part Number
M685-0y-xx-xx
M685-01-BA-BH
125.0000
DA
168.0407
BJ
155.5200
BA
172.6423
BK
156.2500
BB
173.3708
BL
156.8324
BC
164.3555
BM
161.1328
BD
153.6000
BO
166.6286
BE
118.7500
BP
167.2820
BF
176.8382
BQ
167.3280
BG
156.1762
BR
167.3316
BH
174.1537
BU
167.7097
BI
174.7031
BV
Table 10: M685-01 Standard Output Frequencies & Order Codes
M685-02 Standard Output Frequencies & Order Codes
156.2500, 161.1328
M685-01-BB-BD
500.0000
CA
672.1627
AJ
622.0800, 669.3266
M685-02-AA-AH
622.0800
AA
690.5692
AK
M685-02-AB-AD
625.0000
AB
693.4830
AL
627.3296
AC
657.4219
AM
644.5313
AD
614.4000
AO
666.5143
AE
475.0000
AP
669.1281
AF
707.3527
AQ
669.3120
669.3266
AG
624.7048
AR
AH
696.6149
AU
670.8386
AI
698.8123
AV
625.0000, 644.5313
Table 9: Example Order Numbers
Table 11: M685-02 Standard Output Frequencies & Order Codes
Consult IDT for the availability of other frequencies
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.
M685 Datasheet Rev 0.7
6 of 7
Revised 29Jul2009
I n t e g r a t e d D e v i c e Te c h n o l o g y, I n c . ● C o m m u n i c a t i o n M o d u l e s ● w w w. i d t . c o m ● t e l ( 5 0 8 ) 8 5 2 - 5 4 0 0
Errata
M685
DUAL SAW, SELECTABLE FREQUENCY VCSO
PRODUCT APPLICATION CAUTION
F_SEL Change During Power-Up Can Affect Output Frequency Accuracy
M685E1
The M685 features an F_SEL input which is used to select the internal VCSO frequency.
The F_SEL input logic level should not be changed while the M685 device is in operation (that is, voltage
is applied to the pin VCC), particularly when the pin VIN (the control voltage input) is above 2.0V.
Changing the F_SEL input logic level during operation may result in an erroneous output frequency.
It is safe to change F_SEL during operation if pin VIN can be held low, or at least below 2.0V.
M685 Datasheet Rev 0.7 - Errata
Revised 29Jul2009
I n t e g r a t e d D e v i c e Te c h n o l o g y, I n c . ● C o m m u n i c a t i o n M o d u l e s ● w w w. i d t . c o m ● t e l ( 5 0 8 ) 8 5 2 - 5 4 0 0