The Smart Timing Choice
The Smart Timing Choice
SiTime Corporation 990 Almanor Avenue, Sunnyvale, CA 94085 (408) 328-4400 www.sitime.com
Rev. 1.01 Revised January 8, 2015
SiT3808
1 MHz to 80 MHz High Performance MEMS VCXO
Features Applications
Any frequency between 1 MHz and 80 MHz with 6 decimal places of
accuracy
Telecom clock synchronization, instrumentation
Low bandwidth analog PLL, jitter cleaner, clock recovery, audio
100% pin-to-pin drop-in replacement to quartz-based VCXO Video, 3G/HD-SDI, FPGA, broadband and networking
Frequency stability as tight as ±10 ppm
Widest pull range options from ±25 ppm to ±1600 ppm
Industrial or extended commercial temperature range
Superior pull range linearity of ≤1%, 10 times better than quartz
LVCMOS/LVTTL compatible output
Four industry-standard packages: 2.5 mm x 2.0 mm (4-pin),
3.2 mm x 2.5mm (4-pin), 5.0 mm x 3.2 mm (6-pin), 7.0 mm x 5.0 mm
(6-pin)
Instant samples with Time Machine II and field programmable
oscillators
RoHS and REACH compliant, Pb-free, Halogen-free and
Antimony-free
Electrical Specifications
Table 1. Electrical Characteristics[1, 2, 3]
Parameter Symbol Min. Typ. Max. Unit Condition
Frequency Range
Output Frequency Range f1–80MHz
Frequency Stability and Aging
Frequency Stability F_stab -10 – +10 ppm Inclusive of Initial tolerance[4] at 25 °C, and variation over
temperature, rated supply voltage and load.
-25 – +25 ppm
-50 – +50 ppm
Aging F_aging -5 – +5 ppm 10 years, 25°C
Operating Temperature Range T_use -20 – +70 °C Extended Commercial
-40 – +85 °C Industrial
Supply Voltage and Current Consumption
Supply Voltage Vdd 1.71 1.8 1.89 V Additional supply voltages between 2.5V and 3.3V can be
supported. Contact SiTime for additional information.
2.25 2.5 2.75 V
2.52 2.8 3.08 V
2.97 3.3 3.63 V
Current Consumption Idd –3133mA
No load condition, f = 20 MHz, Vdd = 2.5V, 2.8V or 3.3V
–2931mA
No load condition, f = 20 MHz, Vdd = 1.8V
Standby Current I_std ––70AVdd = 2.5V, 2.8V, 3.3V, ST = GND, output is Weakly Pulled Down
––10AVdd = 1.8V, ST = GND, output is Weakly Pulled Down
VCXO Characteristics
Pull Range[5, 6] PR ±25, ±50, ±100, ±150, ±200,
±400, ±800, ±1600
ppm See the Absolute Pull Range and APR table on page 10
Upper Control Voltage VC_U 1.7 – – V Vdd = 1.8V, Voltage at which maximum deviation is guaranteed.
2.4 – – V Vdd = 2.5V, Voltage at which maximum deviation is guaranteed.
2.7 – – V Vdd = 2.8V, Voltage at which maximum deviation is guaranteed.
3.2 – – V Vdd = 3.3V, Voltage at which maximum deviation is guaranteed.
Lower Control Voltage VC_L ––0.1V
Voltage at which minimum deviation is guaranteed.
Control Voltage Input Impedance Z_in 100 – – kΩ
Control Voltage Input Capacitance C_in –5–pF
Linearity Lin –0.11%
Frequency Change Polarity –Positive slope –
Control Voltage Bandwidth (-3dB)
V_BW –8–kHz
Contact SiTime for 16 kHz and other high bandwidth options
The Smart Timing Choice
The Smart Timing Choice
SiT3808
1 MHz to 80 MHz High Performance MEMS VCXO
Rev. 1.01 Page 2 of 11 www.sitime.com
Notes:
1. All electrical specifications in the above table are specified with 15 pF output load and for all Vdd(s) unless otherwise stated.
2. The typical value of any parameter in the Electrical Characteristics table is specified for the nominal value of the highest voltage option for that parameter and at
25°C temperature.
3. All max and min specifications are guaranteed across rated voltage variations and operating temperature ranges, unless specified otherwise
4. Initial tolerance is measured at Vin = Vdd/2
5. Absolute Pull Range (APR) is defined as the guaranteed pull range over temperature and voltage.
6. APR = pull range (PR) - frequency stability (F_stab) - Aging (F_aging)
Electrical Specifications (continued)
Table 1. Electrical Characteristics[1, 2, 3]
Parameter Symbol Min. Typ. Max. Unit Condition
LVCMOS Output Characteristics
Duty Cycle DC 45–55%
All Vdds. Refer to Note 11 for definition of Duty Cycle
Rise/Fall Time Tr, Tf –1.52ns
Vdd = 1.8V, 2.5v, 2.8V or 3.3V, 10% - 90% Vdd level
Output High Voltage VOH 90% – – Vdd IOH = -7 mA (Vdd = 3.0V or 3.3V)
IOH = -4 mA (Vdd = 2.8V or 2.5V)
IOH = -2 mA (Vdd = 1.8V)
Output Low Voltage VOL – – 10% Vdd IOL = 7 mA (Vdd = 3.0V or 3.3V)
IOL = 4 mA (Vdd = 2.8V or 2.5V)
IOL = 2 mA (Vdd = 1.8V)
Input Characteristics
Input Pull-up Impedance Z_in – 100 250 kΩ For the OE/ST pin for 6-pin devices
Input Capacitance C_in – 5 – pF For the OE/ST pin for 6-pin devices
Startup and Resume Timing
Startup Time T_start – – 10 ms See Figure 7 for startup resume timing diagram
OE Enable/Disable Time T_oe – – 180 ns f = 40 MHz, all Vdds. For other freq, T_oe = 100 ns + 3 clock
periods
Resume Time T_resume –710ms
See Figure 8 for resume timing diagram
Jitter
RMS Period Jitter T_jitt – 1.5 2 ps f = 20 MHz, Vdd = 2.5V, 2.8V or 3.3V
– 2 3 ps f = 20 MHz, Vdd = 1.8V
RMS Phase Jitter (random) T_phj – 0.5 1 ps f = 20 MHz, Integration bandwidth = 12 kHz to 20 MHz, All Vdds
The Smart Timing Choice
The Smart Timing Choice
SiT3808
1 MHz to 80 MHz High Performance MEMS VCXO
Rev. 1.01 Page 3 of 11 www.sitime.com
Table 2. Pin Description. 4-Pin Configuration
(For 2.5 x 2.0 mm and 3.2 x 2.5 mm packages)
Pin Symbol Functionality
1 VIN Input 0-Vdd: produces voltage dependent frequency change
2 GND Power Electrical ground
3 CLK Output Oscillator output
4 VDD Power Power supply voltage[7]
Note:
7. A capacitor value of 0.1 µF between VDD and GND is recommended.
Table 3. Pin Description. 6-Pin Configuration
(For 5.0 x 3.2 mm and 7.0 x 5.0 mm packages)
Pin Symbol Functionality
1 VIN Input 0-Vdd: produces voltage dependent frequency change
2 NC/OE/ ST
No
Connect
H or L or Open: No effect on output frequency or other device
functions
Output
Enable
H or Open[8]: specified frequency output
L: output is high
Standby H or Open[8]: specified frequency output
L: output is low (weak pull down)[9]. Oscillation stops
3 GND Power Electrical ground
4 CLK Output Oscillator output
5NC
No
Connect
H or L or Open: No effect on output frequency or other device
functions
6 VDD Power Power supply voltage[10]
Notes:
8. In OE or ST mode, a pull-up resistor of 10 kΩ or less is recommended if pin 2 in the 6-pin package is not externally driven. If pin 2 needs to be left floating, use
the NC option
9. Typical value of the weak pull-down impedance is 5 mΩ
10. A capacitor value of 0.1 µF between VDD and GND is recommended.
Table 4. Absolute Maximum Limits
Attempted operation outside the absolute maximum ratings may cause permanent damage to the part. Actual performance of
the IC is only guaranteed within the operational specifications, not at absolute maximum ratings.
Parameter Min. Max. Unit
Storage Temperature -65 150 °C
VDD -0.5 4 V
Electrostatic Discharge –2000V
Soldering Temperature (follow standard Pb free soldering guidelines) – 260 °C
Table 5. Thermal Consideration
Parameter
JA, 4 Layer Board
(°C/W)
JA, 2 Layer Board
(°C/W)
JC, Bottom
(°C/W)
7050 191 263 30
5032 97 199 24
3225 109 212 27
2520 117 222 26
Table 6. Environmental Compliance
Parameter Condition/Test Method
Mechanical Shock MIL-STD-883F, Method 2002
Mechanical Vibration MIL-STD-883F, Method 2007
Temperature Cycle JESD22, Method A104
Solderability MIL-STD-883F, Method 2003
Moisture Sensitivity Level MSL1 @ 260°C
1 6
VIN VDD
52 NC
43
GND CLK
NC/OE/ST
1 4
VIN VDD
32
GND CLK
Top View
Top View
Figure 2.
Figure 1.
The Smart Timing Choice
The Smart Timing Choice
SiT3808
1 MHz to 80 MHz High Performance MEMS VCXO
Rev. 1.01 Page 4 of 11 www.sitime.com
Note:
11. Duty Cycle is computed as Duty Cycle = TH/Period.
12. SiT3808 supports the configurable duty cycle feature. For custom duty cycle at any given frequency, contact SiTime.
Phase Noise Plot
Figure 3. Phase Noise, 10 MHz, 3.3V, LVCMOS Output
Test Circuit and Waveform
Figure 4. Test Circuit (4-Pin Device) Figure 5. Test Circuit (6-Pin Device)
Figure 6. Waveform
10
310
410
510
6
-170
-160
-150
-140
-130
-120
-110
-100
Frequency Offset (Hz)
Phase Noise (dBc/Hz)
Integrated random phase jitter (RMS, 12kHz-5MHz): 0.52ps
4
1
3
2
0.1µF
Power
Supply
OE/ST Function
Test
Point
15pF
(including probe
and fixture
capacitance)
Vdd Vout
Vc
6
1
4
3
0.1µF
Power
Supply
OE/ST Function
Test
Point
15pF
(including probe
and fixture
capacitance)
Vout
Vc
5
2
Vdd
90% Vdd
High Pulse
(TH)
50%
10% Vdd
Period
tftr
Low Pulse
(TL)
The Smart Timing Choice
The Smart Timing Choice
SiT3808
1 MHz to 80 MHz High Performance MEMS VCXO
Rev. 1.01 Page 5 of 11 www.sitime.com
Timing Diagram
Figure 7. Startup Timing (OE/ST Mode) Figure 8. Standby Resume Timing (ST Mode Only)
u
Figure 9. OE Enable Timing (OE Mode Only) Figure 10. OE Disable Timing (OE Mode Only)
Notes:
13. SiT3808 supports “no runt” pulses and “no glitch” output during startup or resume.
14. SiT3808 supports gated output which is accurate within rated frequency stability from the first cycle.
80% Vdd, 2.5/2.8/3.3V devices
80% Vdd, 1.8V devices Vdd
Pin 4 Voltage
CLK Output
T_start
T_start: Time to start from power-off
No Glitch
during start up
50% Vdd
Vdd
ST Voltage
CLK Output
T_resume
T_resume: Time to resume from ST
50% Vdd
Vdd
OE Voltage
CLK Output
T_oe: Time to put the output in High Z mode
HZ
T_oe
The Smart Timing Choice
The Smart Timing Choice
SiT3808
1 MHz to 80 MHz High Performance MEMS VCXO
Rev. 1.01 Page 6 of 11 www.sitime.com
Programmable Drive Strength
The SiT3808 includes a programmable drive strength feature
to provide a simple, flexible tool to optimize the clock rise/fall
time for specific applications. Benefits from the programmable
drive strength feature are:
• Improves system radiated electromagnetic interference
(EMI) by slowing down the clock rise/fall time.
• Improves the downstream clock receiver’s (RX) jitter by de-
creasing (speeding up) the clock rise/fall time.
• Ability to drive large capacitive loads while maintaining full
swing with sharp edge rates.
For more detailed information about rise/fall time control and
drive strength selection, see the SiTime Application Notes
section; http://www.sitime.com/support/application-notes.
EMI Reduction by Slowing Rise/Fall Time
Figure 11 shows the harmonic power reduction as the rise/fall
times are increased (slowed down). The rise/fall times are
expressed as a ratio of the clock period. For the ratio of 0.05,
the signal is very close to a square wave. For the ratio of 0.45,
the signal is very close to near-triangular waveform. These
results, for example, show that the 11th clock harmonic can be
reduced by 35 dB if the rise/fall edge is increased from 5% of
the period to 45% of the period.
Figure 11. Harmonic EMI reduction as a Function of
Slower Rise/Fall Time
Jitter Reduction with Faster Rise/Fall Time
Power supply noise can be a source of jitter for the
downstream chipset. One way to reduce this jitter is to
increase rise/fall time (edge rate) of the input clock. Some
chipsets would require faster rise/fall time in order to reduce
their sensitivity to this type of jitter. Refer to the Rise/Fall Time
Tables to determine the proper drive strength.
High Output Load Capability
The rise/fall time of the input clock varies as a function of the
actual capacitive load the clock drives. At any given drive
strength, the rise/fall time becomes slower as the output load
increases. As an example, for a 3.3V SiT3808 device with
default drive strength setting, the typical rise/fall time is
1.15 ns for 15 pF output load. The typical rise/fall time slows
down to 2.72 ns when the output load increases to 45 pF. One
can choose to speed up the rise/fall time to 1.41 ns by then
increasing the drive strength setting to “P” (reference to the
drive strength code in Table 10) on the SiT3808.
The SiT3808 can support up to 60 pF maximum capacitive
loads. Refer to the Rise/Tall Time Tables to determine the
proper drive strength for the desired combination of output
load vs. rise/fall time.
SiT3808 Drive Strength Selection
Tables 7 through 10 define the rise/fall times for a given capac-
itive load and supply voltage.
1. Select the table that matches the SiT3808 nominal supply
voltage (1.8V, 2.5V, 2.8V, 3.3V).
2. Select the capacitive load column that matches the appli-
cation requirement (5 pF to 60 pF)
3. Under the capacitive load column, select the desired
rise/fall times.
4. The left-most column represents the part number code for
the corresponding drive strength.
5. Add the drive strength code to the part number for ordering
purposes.
Calculating Maximum Frequency
Based on the rise and fall time data given in Tables 7 through
10, the maximum frequency the oscillator can operate with
guaranteed full swing of the output voltage over temperature
can be calculated as follows:
Where Trf_10/90 is the typical rise/fall time at 10% to 90% Vdd.
Example 1
Calculate fMAX for the following condition:
• Vdd = 3.3V (Table 10)
• Capacitive Load: 30 pF
• Typical Tr/f time = 1.66 ns (drive strength part number code
= G)
Part number for the above example:
SiT3808AIGG2-33EH-49.152000
Drive strength code is inserted here. Default setting is “-”
1357911
-80
-70
-60
-50
-40
-30
-20
-10
0
10
Harmonic number
Harmonic amplitude (dB)
trise=0.05
trise=0.1
trise=0.15
trise=0.2
trise=0.25
trise=0.3
trise=0.35
trise=0.4
trise=0.45
=1
6 x Trf_10/90
Max Frequency
The Smart Timing Choice
The Smart Timing Choice
SiT3808
1 MHz to 80 MHz High Performance MEMS VCXO
Rev. 1.01 Page 7 of 11 www.sitime.com
Rise/Fall Time (10% to 90%) vs CLOAD Tables
Table 7. Vdd = 1.8V Rise/Fall Times for Specific CLOAD Table 8. Vdd = 2.5V Rise/Fall Times for Specific CLOAD
Table 9. Vdd = 2.8V Rise/Fall Times for Specific CLOAD Table 10. Vdd = 3.3V Rise/Fall Times for Specific CLOAD
Drive Strength \ CLOAD 5 pF 15 pF 30 pF 45 pF 60 pF
L12.45 17.68 19.48 46.21 57.82
A6.50 10.27 16.21 23.92 30.73
R4.38 7.05 11.61 16.17 20.83
B3.27 5.30 8.89 12.18 15.75
S2.62 4.25 7.20 9.81 12.65
D2.19 3.52 6.00 8.31 10.59
T1.76 3.01 5.14 7.10 9.15
E1.59 2.59 4.49 6.25 7.98
U1.49 2.28 3.96 5.55 7.15
F1.22 2.10 3.57 5.00 6.46
W1.07 1.88 3.23 4.50 5.87
G1.01 1.64 2.95 4.12 5.40
X0.96 1.50 2.74 3.80 4.98
K0.92 1.41 2.56 3.52 4.64
Y0.88 1.34 2.39 3.25 4.32
Q0.86 1.29 2.24 3.04 4.06
Z or "-": Default 0.82 1.24 2.07 2.89 3.82
M0.77 1.20 1.94 2.72 3.61
N0.66 1.15 1.84 2.58 3.41
P0.51 1.09 1.76 2.45 3.24
Rise/Fall Time Typ (ns)
Drive Strength \ CLOAD 5 pF 15 pF 30 pF 45 pF 60 pF
L8.68 13.59 18.36 32.70 42.06
A4.42 7.18 11.93 16.60 21.38
R2.93 4.78 8.15 11.19 14.59
B2.21 3.57 6.19 8.55 11.04
S1.67 2.87 4.94 6.85 8.80
D1.50 2.33 4.11 5.68 7.33
T1.06 2.04 3.50 4.84 6.26
E0.98 1.69 3.03 4.20 5.51
U0.93 1.48 2.69 3.73 4.92
F0.90 1.37 2.44 3.34 4.42
W0.87 1.29 2.21 3.04 4.02
G or "-": Default 0.67 1.20 2.00 2.79 3.69
X0.44 1.10 1.86 2.56 3.43
K0.38 0.99 1.76 2.37 3.18
Y0.36 0.83 1.66 2.20 2.98
Q0.34 0.71 1.58 2.07 2.80
Z0.33 0.65 1.51 1.95 2.65
M0.32 0.62 1.44 1.85 2.50
N0.31 0.59 1.37 1.77 2.39
P0.30 0.57 1.29 1.70 2.28
Rise/Fall Time Typ (ns)
Drive Strength \ CLOAD 5 pF 15 pF 30 pF 45 pF 60 pF
L7.93 12.69 17.94 30.10 38.89
A4.06 6.66 11.04 15.31 19.80
R2.68 4.40 7.53 10.29 13.37
B2.00 3.25 5.66 7.84 10.11
S1.59 2.57 4.54 6.27 8.07
D1.19 2.14 3.76 5.21 6.72
T1.00 1.79 3.20 4.43 5.77
E0.94 1.51 2.78 3.84 5.06
U0.90 1.38 2.48 3.40 4.50
F0.87 1.29 2.21 3.03 4.05
W0.62 1.19 1.99 2.76 3.68
G or "-": Default 0.41 1.08 1.84 2.52 3.36
X0.37 0.96 1.72 2.33 3.15
K0.35 0.78 1.63 2.15 2.92
Y0.33 0.67 1.54 2.00 2.75
Q0.32 0.63 1.46 1.89 2.57
Z0.31 0.60 1.39 1.80 2.43
M0.30 0.57 1.31 1.72 2.30
N0.30 0.56 1.22 1.63 2.22
P0.29 0.54 1.13 1.55 2.13
Rise/Fall Time Typ (ns)
Drive Strength \ CLOAD 5 pF 15 pF 30 pF 45 pF 60 pF
L7.18 11.59 17.24 27.57 35.57
A3.61 6.02 10.19 13.98 18.10
R2.31 3.95 6.88 9.42 12.24
B1.65 2.92 5.12 7.10 9.17
S1.43 2.26 4.09 5.66 7.34
D1.01 1.91 3.38 4.69 6.14
T0.94 1.51 2.86 3.97 5.25
E0.90 1.36 2.50 3.46 4.58
U0.86 1.25 2.21 3.03 4.07
F or "-": Default 0.48 1.15 1.95 2.72 3.65
W0.38 1.04 1.77 2.47 3.31
G0.36 0.87 1.66 2.23 3.03
X0.34 0.70 1.56 2.04 2.80
K0.33 0.63 1.48 1.89 2.61
Y0.32 0.60 1.40 1.79 2.43
Q0.32 0.58 1.31 1.69 2.28
Z0.30 0.56 1.22 1.62 2.17
M0.30 0.55 1.12 1.54 2.07
N0.30 0.54 1.02 1.47 1.97
P0.29 0.52 0.95 1.41 1.90
Rise/Fall Time Typ (ns)
The Smart Timing Choice
The Smart Timing Choice
SiT3808
1 MHz to 80 MHz High Performance MEMS VCXO
Rev. 1.01 Page 8 of 11 www.sitime.com
Instant Samples with Time Machine and
Field Programmable Oscillators
SiTime supports a field programmable version of the SiT3808
low power oscillator for fast prototyping and real time custom-
ization of features. The field programmable devices (FP
devices) are available for all four standard SiT3808 package
sizes and can be configured to one’s exact specification using
the Time Machine II, an USB powered MEMS oscillator
programmer.
Customizable Features of the SiT3808 FP Devices Include
• Any frequency between 1 and 80 MHz
• Three frequency stability options: ±10 ppm, ±25 ppm,
±50 ppm
• Two operating temperatures: -20 to 70°C or -40 to 85°C
• Four supply voltage options: 1.8V, 2.5V, 2.8V, and 3.3V
• Eight pull range options: ±25 ppm, ±50 ppm, ±100 ppm,
±150 ppm, ±200 ppm, ±400 ppm, ±800 ppm, ±1600 ppm
For more information regarding SiTime’s field programmable
solutions, visit http://www.sitime.com/time-machine and
http://www.sitime.com/fp-devices.
SiT3808 is typically factory-programmed per customer
ordering codes for volume delivery.
The Smart Timing Choice
The Smart Timing Choice
SiT3808
1 MHz to 80 MHz High Performance MEMS VCXO
Rev. 1.01 Page 9 of 11 www.sitime.com
Note:
15.Top marking: Y denotes manufacturing origin and XXXX denotes manufacturing lot number. The value of “Y” will depend on the assembly location of the device.
Dimensions and Patterns
Package Size – Dimensions (Unit: mm)[15] Recommended Land Pattern (Unit: mm)
2.7 x 2.4 x 0.75 mm (100% compatible with 2.5 x 2. 0 mm footprint)
3.2 x 2.5 x 0.75 mm
5.0 x 3.2 x 0.75 mm
7.0 x 5.0x 0.90 mm
YXXXX
2.7 ± 0.05 1.00
0.75 ± 0.05
2.4 ± 0.05
0.85
1.25
0.50
1.9
1.1
1.5
1.0
3.2 ± 0.05
2.5 ± 0.05
2.1
0.9
0.7
0.9
0.75 ± 0.05
#1
#2
#4#3
#2
#1
#3#4
YXXXX
2.2
1.9
1. 4
1.2
0.75±0.05
YXXXX
1.20
#2
#5
#2
#5
#1#3
#4 #6
#1 #3
#4#6
5.0±0.10
1.40
1.10
5.08
7.0±0.10
2.60
#1 #3
#6 #4
#1#3
#6
#4
0.90 ±0.10
#2
#5
#2
#5
YXXXX
5.08
1.60
1.60
3.80
The Smart Timing Choice
The Smart Timing Choice
SiT3808
1 MHz to 80 MHz High Performance MEMS VCXO
Rev. 1.01 Page 10 of 11 www.sitime.com
Ordering Information
Note:
16. “–” indicates “not available.”
Table 12. APR Definition
Absolute pull range (APR) = Norminal pull range (PR) - frequency stability (F_stab) - Aging (F_aging)
Frequency Stability
Nominal Pull Range ± 10 ± 25 ± 50
APR (PPM)
± 25 ± 10 – –
± 50 ± 35 ± 20 –
± 100 ± 85 ± 70 ± 45
± 150 ± 135 ± 120 ± 95
± 200 ± 185 ± 170 ± 145
± 400 ± 385 ± 370 ± 345
± 800 ± 785 ± 770 ± 745
± 1600 ± 1585 ± 1570 ± 1545
Table 13. Ordering Codes for Supported Tape & Reel Packing Method[16]
Device Size 12 mm T&R (3ku) 12 mm T&R (1ku) 8 mm T&R (3ku) 8 mm T&R 1ku)
2.5 x 2.0 mm – – D E
3.2 x 2.5 mm – – D E
5.0 x 3.2 mm T Y – –
7.0 x 5.0 mm T Y – –
SiT3808AC -22-33EH-49.152000D
Frequency
1.000000 to 80.000000 MHz
Part Family
“SiT3808”
Revision Letter
“A” is the revision
Temperature Range
“I” Industrial, -40 to 85ºC
Supply Voltage
“18” for 1.8 V ±5%
“25” for 2.5 V ±10%
“28” for 2.8 V ±10%
“33” for 3.3 V ±10%
Pull Range Options
“C” Commercial, -20 to 70ºC
Frequency Stability
“F” for ±10 ppm
“2” for ±25 ppm
“3” for ±50 ppm
Package
“C” 6-pin, 5.0 x 3.2 mm x mm
“D” 6-pin, 7.0 x 5.0 mm x mm
“M” for ±25 ppm
“B” for ±50 ppm
“E” for ±100 ppm
“G” for ±150 ppm
“H” for ±200 ppm
“X” for ±400 ppm
“Y” for ±800 ppm
“Z” for ±1600 ppm
“2” 4-pin, 3.2 x 2.5 mm x mm
Feature Pin
“E” for Output Enable (6-pin only)
“S” for Standby (6-pin only)
“N” for No Connect in 6-pin devices,
Default value in 4-pin device
“G” 2.5 x 2.0 mm x mm
Packing Method
“T”: 12 mm Tape & Reel, 3ku reel
“Y”: 12 mm Tape & Reel, 1ku reel
“D”: 8 mm Tape & Reel, 3ku reel
“E”: 8 mm Tape & Reel, 1ku reel
Blank for Bulk
Output Drive Strength
“–” Default (datasheet limits)
See rise/fall tables on page 7
“L”
“A”
“R”
“B”
“S”
“D”
“T”
“E”
“U”
“F”
“W”
“G”
“X”
“K”
“Y”
“Q”
“Z”
“M”
“N”
“P”
Rev. 1.01 Page 11 of 11 www.sitime.com
© SiTime Corporation 2015. The information contained herein is subject to change at any time without notice. SiTime assumes no responsibility or liability for any loss, damage or defect of a
Product which is caused in whole or in part by (i) use of any circuitry other than circuitry embodied in a SiTime product, (ii) misuse or abuse including static discharge, neglect or accident, (iii)
unauthorized modification or repairs which have been soldered or altered during assembly and are not capable of being tested by SiTime under its normal test conditions, or (iv) improper
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The Smart Timing Choice
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1 MHz to 80 MHz High Performance MEMS VCXO
SiT3808
Table 14. Additional Information
Document Description Download Link
Manufacturing
Notes
Tape & Reel dimension,
reflow profile and other
manufacturing related info
http://www.sitime.com/component/docman/doc_download/85-manufaturing-notes-for-sitime-oscillators
Qualification
Reports
RoHS report, reliability reports,
composition reports
http://www.sitime.com/support/quality-and-reliability
Performance
Reports
Additional performance data
such as phase noise, current
consumption and jitter for
selected frequencies
http://www.sitime.com/support/performance-measurement-report
Termination
Techniques
Termination design
recommendations
http://www.sitime.com/support/application-notes
Layout Techniques Layout recommendations http://www.sitime.com/support/application-notes
VCXO
Specifications
Definition of key VCXO
specifications such as
APR and Kv
http://www.sitime.com/support2/documents/AN10020_VCXO_SpecDefinitions_rev1.pdf
VCXO in PLL
Design
Selection of VCXO parameters
and trade-offs in PLL designs
http://www.sitime.com/support2/documents/AN10021_VCXO_PLL_Design_Guidelines_1v0.pdf
Revision History
Table 15. Datasheet Version and Change Log
Version Release Date Change Summary
0.6 1/24/2013 Preliminary
1.0 3/7/14 • Preliminary removed from title
• Updated features and application
• Updated electrical specifications table
• Updated figure 4,
• Added new 6-pin device for figure 5
• Updated timing diagrams
• Updated programmable drive strength section
• Updated ordering information drawing
• Updated APR table
• Updated ordering codes for tape and reel table
• Reformatted additional information table columns
1.01 1/8/15 • Corrected CLK and VDD functionality description in Table 2
• Revised VIN functionality description in Table 3
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SiTime Corporation 990 Almanor Avenue, Sunnyvale, CA 94085 (408) 328-4400 www.sitime.com
Supplemental Information
The Supplemental Information section is not part of the datasheet and is for informational purposes only.
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SiTime Corporation 990 Almanor Avenue, Sunnyvale, CA 94085 (408) 328-4400 www.sitime.com
Silicon MEMS Outperforms Quartz Rev. 1.1 Revised October 5, 2013
Silicon MEMS Outperforms Quartz
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Silicon MEMS Outperforms Quartz
Silicon MEMS Outperforms Quartz Rev. 1.1 www.sitime.com
Best Reliability
Silicon is inherently more reliable than quartz. Unlike quartz
suppliers, SiTime has in-house MEMS and analog CMOS
expertise, which allows SiTime to develop the most reliable
products. Figure 1 shows a comparison with quartz
technology.
Why is SiTime Best in Class:
• SiTime’s MEMS resonators are vacuum sealed using an
advanced EpiSeal™ process, which eliminates foreign par-
ticles and improves long term aging and reliability
• World-class MEMS and CMOS design expertise
Figure 1. Reliability Comparison[1]
Best Aging
Unlike quartz, MEMS oscillators have excellent long term
aging performance which is why every new SiTime product
specifies 10-year aging. A comparison is shown in Figure 2.
Why is SiTime Best in Class:
• SiTime’s MEMS resonators are vacuum sealed using an
advanced EpiSeal process, which eliminates foreign parti-
cles and improves long term aging and reliability
• Inherently better immunity of electrostatically driven
MEMS resonator
Figure 2. Aging Comparison[2]
Best Electro Magnetic Susceptibility (EMS)
SiTime’s oscillators in plastic packages are up to 54 times
more immune to external electromagnetic fields than quartz
oscillators as shown in Figure 3.
Why is SiTime Best in Class:
• Internal differential architecture for best common mode
noise rejection
• Electrostatically driven MEMS resonator is more immune
to EMS
Figure 3. Electro Magnetic Susceptibility (EMS)[3]
Best Power Supply Noise Rejection
SiTime’s MEMS oscillators are more resilient against noise on
the power supply. A comparison is shown in Figure 4.
Why is SiTime Best in Class:
• On-chip regulators and internal differential architecture for
common mode noise rejection
• Best analog CMOS design expertise
Figure 4. Power Supply Noise Rejection[4]
Mean Time Between Failure (Million Hours)
14
16
28
38
500
0200 400 600
Pericom
TXC
Epson
IDT (Fox)
SiTime
SiTime
20X Better
1.5
3.5
3.0
8.0
0
2
4
6
8
10
1-Year 10-Year
SiTime MEMS vs. Quartz Aging
SiTime MEMS Oscillator Quartz Oscillator
Aging (±PPM)
SiTime
2X Better
- 39 - 40 - 42 - 43 - 45
- 73
- 90
- 80
- 70
- 60
- 50
- 40
- 30
Kyocera Epson TXC CW SiLabs SiTime
SiTime vs Quartz
Electro Magnetic Susceptibility (EMS)
Average Spurs (dB)
SiTime
54X Better
0.0
1.0
2.0
3.0
4.0
5.0
10 100 1,000 10,000
Additive Integrated Phase Jitter per mVp-p
Injected Noise (ps/mv)
Power Supply Noise Frequency (kHz)
Power Supply Noise Rejection
SiTIme NDK Epson Kyocera
SiTime
SiTime
3X Better
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Silicon MEMS Outperforms Quartz
Silicon MEMS Outperforms Quartz Rev. 1.1 www.sitime.com
Best Vibration Robustness
High-vibration environments are all around us. All electronics,
from handheld devices to enterprise servers and storage
systems are subject to vibration. Figure 5 shows a comparison
of vibration robustness.
Why is SiTime Best in Class:
• The moving mass of SiTime’s MEMS resonators is up to
3000 times smaller than quartz
• Center-anchored MEMS resonator is the most robust
design
Figure 5. Vibration Robustness[5]
Best Shock Robustness
SiTime’s oscillators can withstand at least 50,000 g shock.
They all maintain their electrical performance in operation
during shock events. A comparison with quartz devices is
shown in Figure 6.
Why is SiTime Best in Class:
• The moving mass of SiTime’s MEMS resonators is up to
3000 times smaller than quartz
• Center-anchored MEMS resonator is the most robust
design
Figure 6. Shock Robustness[6]
Vibration Sensitivity (ppb/g)
0.10
1.00
10.00
100.00
10 100 1000
Vibration Frequency (Hz)
Vibration Sensitivity vs. Frequency
SiTime TXC Epson Connor Winfield Kyocera SiLabs
SiTime
Up to 30x
Better
14.3
12.6
3.9
2.9 2.5
0.6
0
2
4
6
8
10
12
14
16
K
y
ocer
a
E
p
son TXC CW SiLab
s
SiTime
Differential XO Shock Robustness - 500 g
SiTime
Up to 25x
Better
Peak Frequency Deviation (PPM)
Notes:
1. Data Source: Reliability documents of named companies.
2. Data source: SiTime and quartz oscillator devices datasheets.
3. Test conditions for Electro Magnetic Susceptibility (EMS):
• According to IEC EN61000-4.3 (Electromagnetic compatibility standard)
• Field strength: 3V/m
• Radiated signal modulation: AM 1 kHz at 80% depth
• Carrier frequency scan: 80 MHz – 1 GHz in 1% steps
• Antenna polarization: Vertical
• DUT position: Center aligned to antenna
Devices used in this test:
SiTime, SiT9120AC-1D2-33E156.250000 - MEMS based - 156.25 MHz
Epson, EG-2102CA 156.2500M-PHPAL3 - SAW based - 156.25 MHz
TXC, BB-156.250MBE-T - 3rd Overtone quartz based - 156.25 MHz
Kyocera, KC7050T156.250P30E00 - SAW based - 156.25 MHz
Connor Winfield (CW), P123-156.25M - 3rd overtone quartz based - 156.25 MHz
SiLabs, Si590AB-BDG - 3rd overtone quartz based - 156.25 MHz
4. 50 mV pk-pk Sinusoidal voltage.
Devices used in this test:
SiTime, SiT8208AI-33-33E-25.000000, MEMS based - 25 MHz
NDK, NZ2523SB-25.6M - quartz based - 25.6 MHz
Kyocera, KC2016B25M0C1GE00 - quartz based - 25 MHz
Epson, SG-310SCF-25M0-MB3 - quartz based - 25 MHz
5. Devices used in this test: same as EMS test stated in Note 3.
6. Test conditions for shock test:
• MIL-STD-883F Method 2002
• Condition A: half sine wave shock pulse, 500-g, 1ms
• Continuous frequency measurement in 100 μs gate time for 10 seconds
Devices used in this test: same as EMS test stated in Note 3
7. Additional data, including setup and detailed results, is available upon request to qualified customers. Please contact productsupport@sitime.com.
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Document Feedback Form
Feedback Form Rev. 1.0 www.sitime.com
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below to productsupport@sitime.com.
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EMI Termination recommendations Shock and vibration performance Other
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