SM840001
106.25MHz Ultra-Low Jitter Clock
Synthesizer
General Description
The SM840001 synthesizer series were designed for Fibre
Channel applications. The device design is optimized for
106.25MHz or 212.5MHz using a 26.5625MHz
fundamental parallel resonant crystal, with stability and
accuracy over the full operating range. The SM840001
includes a unique power reduction methodology, along
with a patented RotaryWave
TM
architecture, that provides
a stable clock with very low noise for optimized
performance. This yields an overall improved Bit Error
Rate (BER) and improved waveform integrity.
Datasheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
Features
•
Generates a single LVCMOS/LVTTL output
•
Integrated loop filter components
•
RMS Phase Jitter:
- 510 fs (typ) at 106.25MHz
- 320 fs (typ) at 212.50MHz
•
Operates with either a 3.3V or 2.5V supply
•
Power consumption is <77mA @ 3.3 V
•
Fundamental crystal oscillator interface
•
Input frequency of 26.5625 MHz parallel resonant
•
Selectable output frequency: 106.25MHz or 212.5MHz
•
Temperature range: –40°C to +75°C
•
Available in 8-pin TSSOP package
Applications
•
Fibre Channel
•
Storage
___________________________________________________________________________________________________________
Block Diagram
RotaryWave is a trademark of Multigig, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (
408
) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
March 2010
M9999-031810-B
hbwhelp@micrel.com
or (408) 955-1690
Micrel, Inc.
SM840001
Ordering Information
(1)
Part Number
SM840001KA
SM840001KA TR
Note:
1. Devices are Green, RoHS-compliant and PFOS-compliant.
2. Tape and Reel.
(2)
Package
Type
K-8
K-8
Operating Range
-40°C to +75°C
-40°C to +75°C
Package Marking
840001
840001
Lead Finish
NiPdAu
NiPdAu
Pin Configuration
8-Pin TSSOP (K-8)
Pin Description
Pin Number
1
2
3
4
5
6
7
8
Pin Name
VDDA
OE
XTAL OUT
XTAL IN
FSEL
GND
Q0
VDD
Type
P
I
O
I
I
P
O
P
Pull-down
Pull-up
Level
Pin Function
Analog Power.
Output Enable: 1 = Enable, 0 = Disable.
Crystal Out.
Crystal Input.
Frequency Select Pin.
Ground.
Single Ended LVCMOS Clock Out.
Core Power.
Frequency Select Table
FSEL
0
1
Output (MHz)
106.25 (Default)
212.5
Output Enable
OE
0
1
Output
Disable
Enable
March 2010
2
M9999-031810-B
hbwhelp@micrel.com
or (408) 955-1690
Micrel, Inc.
SM840001
Absolute Maximum Ratings
(1)
Supply Voltage (V
DD
)...................................................+4.6V
Input Voltage (V
IN
) ................................ –0.50V to V
DD
+0.5V
Output Voltage (V
OUT
) .......................... –0.50V to V
DD
+0.5V
Lead Temperature (soldering, 20sec.)....................... 260°C
Storage Temperature (T
s
) .........................–65°C to +150°C
Operating Ratings
(2)
Supply Voltage (V
IN
)............................. +2.375V to +3.465V
Ambient Temperature (T
A
) .......................... –40°C to +75°C
Junction Thermal Resistance
TSSOP (θ
JA
).....................................................150°C/W
DC Electrical Characteristics
V
DD
= 2.5V ±5%; T
A
= –40°C to +75°C, unless noted.
Symbol
V
DD
V
DDA
I
DD
I
DDA
Parameter
Core Supply Voltage
Analog Supply Voltage
Core Supply Current
Analog Supply Current
No load
Condition
Min
2.375
2.375
Typ
2.50
2.50
12
48
Max
2.625
2.625
20
55
Units
V
V
mA
mA
DC Electrical Characteristics
V
DD
= 3.3V ±5%; T
A
= -40°C to +75°C, unless noted.
Symbol
V
DD
V
DDA
I
DD
I
DDA
Parameter
Core Supply Voltage
Analog Supply Voltage
Core Supply Current
Analog Supply Current
No load
Condition
Min
3.135
3.135
Typ
3.30
3.30
15
49
Max
3.465
3.465
22
55
Units
V
V
mA
mA
LVCMOS DC Characteristics
V
DD
= 2.5V and 3.3V ±5%; T
A
= -40°C to +75°C, unless noted.
Symbol
V
IH
V
IL
V
OH
V
OL
I
IH
I
IL
I
IH
I
IL
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
Parameter
Input HIGH Voltage
Input LOW Voltage
Output HIGH Voltage
Output LOW Voltage
Input HIGH Current
Input LOW Current
Input HIGH Current
Input LOW Current
Condition
V
DD
= 3.3V ±5%
V
DD
= 2.5V ±5%
V
DD
= 3.3V ±5%
V
DD
= 2.5V ±5%
V
DD
= 3.3V ±5%
V
DD
= 2.5V ±5%
Output Enable input
Output Enable input
FSEL input
FSEL input
Min
2
1.7
-0.30
-0.30
2.6
1.8
Typ
Max
V
DD
+0.3
V
DD
+ 0.3
0.80
0.70
Units
V
V
V
V
V
V
0.5
5
-150
150
-5
V
µA
µA
µA
µA
March 2010
3
M9999-031810-B
hbwhelp@micrel.com
or (408) 955-1690
Micrel, Inc.
SM840001
AC Electrical Characteristics
V
DD
= 2.5V and 3.3V ±5%; T
A
= -40°C to +75°C, unless noted.
Symbol
F
OUT
Parameter
Output Frequency
Condition
FSEL=1
FSEL=0
106.25MHz,
t
JITTER
RMS Phase Jitter
Integration Range: 637kHz to 10MHz
212.50MHz
Integration Range: 2.55MHz to 20MHz
t
R
/ t
F
ODC
Output Rise/Fall Time
Output Duty Cycle
20% to 80%
106.25MHz
212.50MHz
100
48
45
Min
186.66
93.33
Typ
212.5
106.25
510
320
350
52
55
Max
226.66
113.33
Units
MHz
MHz
fs
fs
ps
%
%
3.3V Carrier Frequency, 106.25MHz
Offset from Carrier
100Hz
1kHz
10kHz
100kHz
1MHz
10MHz
40MHz
Measured Phase Noise
-97
-122
-131
-126
-144
-163
-165
Unit
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
3.3V Carrier Frequency, 212.5MHz
Offset from Carrier
100Hz
1kHz
10kHz
100kHz
1MHz
10MHz
40MHz
Measured Phase Noise
-92
-116
-124
-120
-138
-161
-163
Unit
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
dBc/Hz
Crystal Characteristics
Parameter
Mode of Oscillation
Frequency
Equivalent Series Resistance (ESR)
Shunt Capacitor
Drive Level
Condition
Min
Typ
26.5625
50
7
1
Max
Units
MHz
Ω
pF
mW
Fundamental Parallel Resonant
March 2010
4
M9999-031810-B
hbwhelp@micrel.com
or (408) 955-1690
Micrel, Inc.
SM840001
Functional Description
The SM840001 provides a high performance and high
accuracy solution for a precision clock source at 106.25
or 212.50MHz derived from a low cost 26.5625MHz Xtal.
A single 12mA LVCMOS output is provided with tri state
capability, controlled via an external pin (OE).
The design of the SM840001 consumes very low power
in the PLL due to a patented technology in the VCO and
the associated dividers. The VCO range is ~3.2GHz to
3.5GHz providing high resolution and easy integer divide
ratios. Output Divider ratios are fixed at either ÷15 or ÷30
controlled via the FSEL pin, and the feedback divider
also fixed at ÷120. Duty Cycle is inherently improved and
guarantees tight control and stability on this critical
specification. The provides improved specifications for
Duty Cycle, Jitter, Phase Noise, Power Consumption,
and noise sensitivity. Additionally, the SM840001 will
operate at either 3.3V or 2.5V supplies.
Switching Waveforms
RMS Phase Noise/Jitter
Phase Noise Plot: 106.25MHz @ 3.3V
Phase Noise Plot: 212.5MHz @ 3.3V
March 2010
5
M9999-031810-B
hbwhelp@micrel.com
or (408) 955-1690
瑞萨MCU/MPU
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