Ordering Information .................................................................................................................................................................... 2
User Programming Interface ..................................................................................................................................... 18
Start-up output frequency and signaling types ........................................................................................................... 18
Any-frequency function ............................................................................................................................................. 19
C/SPI Control Registers...................................................................................................................................................... 28
9 I
Register Address: 0x00. DCO Frequency Control Least Significant Word (LSW) .................................................... 28
Register Address: 0x01. OE Control, DCO Frequency Control Most Significant Word (MSW) ................................. 29
Register Address: 0x02. DCO PULL RANGE CONTROL ........................................................................................ 29
Register Address: 0x03. Frac-N PLL Feedback Divider Integer Value and Frac-N PLL Feedback Divider Fraction
Value MSW ............................................................................................................................................................... 30
Register Address: 0x05. Forward Divider, Driver Control ......................................................................................... 30
Register Address: 0x06. Driver Divider, Driver Control ............................................................................................. 31
2
C Operation ........................................................................................................................................................................ 32
10 I
I
2
C protocol ............................................................................................................................................................... 32
I
2
C Timing Specification ............................................................................................................................................ 35
I
2
C Device Address Modes ....................................................................................................................................... 36
Dimensions and Patterns ........................................................................................................................................................... 43
Additional Information ................................................................................................................................................................ 44
Revision History ......................................................................................................................................................................... 45
Rev 1.01
Page 3 of 45
www.sitime.com
SiT3521
1 to 340 MHz Elite Platform I2C/SPI Programmable Oscillator
1 Electrical Characteristics
All Min and Max limits in the Electrical Characteristics tables are specified over temperature and rated operating voltage with
standard output terminations shown in the termination diagrams. Typical values are at 25°C and nominal supply voltage.
Table 1. Electrical Characteristics – Common to LVPECL, LVDS and HCSL
Parameter
Output Frequency Range
Symbol
f
Min.
1
Typ.
–
–
–
–
–
±1
–
–
–
Max.
340
Unit
MHz
Condition
Factory or user programmable, accurate to 6 decimal places
Frequency Range
Frequency Stability
Frequency Stability
F_stab
-10
-20
-25
-50
First Year Aging
F_1y
–
+10
+20
+25
+50
–
ppm
ppm
ppm
ppm
ppm
°C
°C
°C
1
st
-year aging at 25°C
Inclusive of initial tolerance, operating temperature, rated
power supply voltage and load variations.
Temperature Range
Operating Temperature Range
T_use
-20
-40
-40
+70
+85
+105
Supply Voltage
Supply Voltage
Vdd
2.97
2.7
2.52
2.25
3.3
3.0
2.8
2.5
–
–
100
–
–
–
3.63
3.3
3.08
2.75
–
30%
–
V
V
V
V
Extended Commercial
Industrial
Extended Industrial. Available only for I
2
C operation, not SPI.
Input Characteristics – OE Pin
Input Voltage High
Input Voltage Low
Input Pull-up Impedance
VIH
VIL
Z_in
70%
–
–
Vdd
Vdd
kΩ
OE pin
OE pin
OE pin, logic high or logic low
Output Characteristics
Duty Cycle
DC
45
–
–
55
%
Startup and Output Enable/Disable Timing
Start-up Time
Output Enable/Disable Time –
Hardware control via OE pin
Output Enable/Disable Time –
Software control via I
2
C/SPI
T_start
T_oe_hw
3.0
3.8
ms
µs
Measured from the time Vdd reaches its rated minimum value
Measured from the time OE pin reaches rated VIH and VIL to
the time clock pins reach 90% of swing and high-Z.
See
Figure 9
and
Figure 10
Measured from the time the last byte of command is
transmitted via I
2
C/SPI (reg1) to the time clock pins reach 90%
of swing and high-Z. See
Figure 30
and
Figure 31
T_oe_sw
–
–
6.5
µs
Rev 1.01
Page 4 of 45
www.sitime.com
SiT3521
1 to 340 MHz Elite Platform I2C/SPI Programmable Oscillator
Table 2. Electrical Characteristics – LVPECL Specific
Parameter
Symbol
Min.
Typ.
Max.
Unit
Condition
Current Consumption
Current Consumption
OE Disable Supply Current
Output Disable Leakage Current
Maximum Output Current
Idd
I_OE
I_leak
I_driver
–
–
–
–
–
–
0.15
–
89
58
–
32
mA
mA
A
mA
Excluding Load Termination Current, Vdd = 3.3 V or 2.5 V
OE = Low
OE = Low
Maximum average current drawn from OUT+ or OUT-
Output Characteristics
Output High Voltage
Output Low Voltage
Output Differential Voltage Swing
Rise/Fall Time
VOH
VOL
V_Swing
Tr, Tf
Vdd - 1.1V
Vdd - 1.9V
1.2
–
–
–
1.6
225
Vdd - 0.7V
Vdd - 1.5V
2.0
290
Jitter
RMS Phase Jitter (random) –
DCO Mode Only
T_phj
–
–
RMS Phase Jitter (random) –
Any-frequency Mode Only
T_phj
–
–
RMS Period Jitter
[3]
Note:
3. Measured according to JESD65B.
T_jitt
–
0.225
0.1
0.225
0.11
1
0.340
0.14
0.340
0.15
1.6
ps
ps
ps
ps
ps
f = 156.25 MHz, Integration bandwidth = 12 kHz to 20 MHz,
all Vdd levels
f = 156.25, IEEE802.3-2005 10 GbE jitter mask integration
bandwidth = 1.875 MHz to 20 MHz, all Vdd levels
f = 156.25 MHz, Integration bandwidth = 12 kHz to 20 MHz,
all Vdd levels
f = 156.25, IEEE802.3-2005 10 GbE jitter mask integration
bandwidth = 1.875 MHz to 20 MHz, all Vdd levels
f = 100, 156.25 or 212.5 MHz, Vdd = 3.3 V or 2.5 V
V
V
V
ps
See
Figure 5
See
Figure 5
See
Figure 6
20% to 80%, see
Figure 6
Table 3. Electrical Characteristics – LVDS Specific
Parameter
Symbol
Min.
Typ.
Max.
Unit
Condition
Current Consumption
Current Consumption
OE Disable Supply Current
Output Disable Leakage Current
Idd
I_OE
I_leak
–
–
–
–
–
0.15
80
61
–
mA
mA
A
Excluding Load Termination Current, Vdd = 3.3 V or 2.5 V
OE = Low
OE = Low
Output Characteristics
Differential Output Voltage
Delta VOD
Offset Voltage
Delta VOS
Rise/Fall Time
VOD
ΔVOD
VOS
ΔVOS
Tr, Tf
250
–
1.125
–
–
–
–
–
–
400
455
50
1.375
50
470
Jitter
RMS Phase Jitter (random) –
DCO Mode Only
T_phj
–
–
RMS Phase Jitter (random) –
Any-frequency Mode Only
T_phj
–
–
RMS Period Jitter
[4]
Note:
4. Measured according to JESD65B.
T_jitt
–
0.21
0.1
0.21
0.1
1
0.275
0.12
0.367
0.12
1.6
ps
ps
ps
ps
ps
f = 156.25 MHz, Integration bandwidth = 12 kHz to 20 MHz,
all Vdd levels
f = 156.25, IEEE802.3-2005 10 GbE jitter mask integration
bandwidth = 1.875 MHz to 20 MHz, all Vdd levels
f = 156.25 MHz, Integration bandwidth = 12 kHz to 20 MHz,
all Vdd levels
f = 156.25, IEEE802.3-2005 10 GbE jitter mask integration
bandwidth = 1.875 MHz to 20 MHz, all Vdd levels
f = 100, 156.25 or 212.5 MHz, Vdd = 3.3 V or 2.5 V
mV
mV
V
mV
ps
f = 156.25MHz See
Figure 7
See
Figure 7
See
Figure 7
See
Figure 7
Measured with 2 pF capacitive loading to GND, 20% to 80%,
[i=s] This post was last edited by learntest on 2019-4-15 12:25 [/i]Where does he get this 26mV? ? 26mV should be the voltage of VE, right? Because re=26mV/ie, but why is ve 1.2v? 81*(26mv/ie)=50 ohms...
For those who love boards, it is a happy thing to see a good board for free evaluation. Now, I want to tell you that there are many good board evaluation activities online in the forum recently. Will ...
Hello, everyone: Today I shared the introductory material on electrical engineering that I learned, "OHM-Illustrated Introduction to Electrical Engineering" by OHM of Japan. This book explains the bas...
Operational amplifiers are widely used in sensing and measurement applications. MSP430 microcontrollers (MCUs) provide a full-signal chain implementation to replace external operational amplifiers by ...
[size=4]The development of Bluetooth 4.0 protocol stack is actually to modify the protocol stack made by TI. It is not too difficult and there is a lot of information now. [/size] [size=4]Let's build ...
Previously, there was the CATL's "lithium mine rebate" promotion order, and now there is BYD's "negative electrode profit sharing" operation. Both "Ning Wang" and "Di Wang" have stirred up the pric...[Details]
1. Introduction:
In today's society, with the continuous progress of science and technology, more and more modern medical electronic equipment has been rapidly developed, especially electr...[Details]
OFweek Cup · OFweek 2023 China
Robot
Industry Annual Selection (abbreviated as OFweek Robot Awards 2023) is jointly organized by OFweek, China's high-tech industry portal, and its authorita...[Details]
sbit DQ=P3^7; //DS18B20 data transmission line connects to the corresponding pin of the microcontroller void delaymm(uint z) { uint x,y; for(x=z;x 0;x--) for(y=110;y 0;y--); } //R...[Details]
The ultra-low power electronic thermometer designed in this paper can measure and display the temperature of the measured point through the temperature sensor, and can be extended and controlle...[Details]
Battery calibration reminder Sina Digital News reported on the morning of April 1 that the iOS 14.5 beta version (beta6) released early this morning introduced a new feature for recalibrating the...[Details]
Information from the State Intellectual Property Office shows that on March 15, Beijing Xiaomi Mobile Software Co., Ltd. was granted the "AR glasses" patent. The patent abstract shows that the AR...[Details]
One of the biggest advantages of LED technology is the ability to generate pure color light with an extremely narrow spectrum in the form of electromagnetic radiation, with high efficiency an...[Details]
On October 8, 2019, the reporter learned from the morning adjustment meeting of State Grid Ningxia Electric Power Co., Ltd. that during the National Day holiday, the Ningxia power grid operated sta...[Details]
According to news on June 15, Tianyancha App showed that Qingchun Semiconductor (Ningbo) Co., Ltd. has recently undergone industrial and commercial changes, and the shareholder has added Hefei NIO In...[Details]
According to foreign media 91 Mobiles, Indian e-commerce portal Flipkart released a promotional poster for the realme 5 series. The poster shows that the realme 5 series will be released in India on ...[Details]
With Apple launching new MacBook Pro, MacBook Air, and Mac mini models with M1 chips this week, it also marks the beginning of Apple's official transition away from Intel processors, and these three ...[Details]
According to MSPoweruser, there are more and more leaks about Samsung Galaxy Note 20 series mobile phones, and recently the battery information about Galaxy Note 20+ has also been exposed. ...[Details]
According to recent data released by the China Energy Storage Alliance (CNESA), the capacity of operational solar energy storage projects in China increased by nearly 70% from 2018 to 2...[Details]
1 Background
The asphalt workshop of the third refining department of Cangzhou Refinery currently has a set of road asphalt equipment with an annual output of 100,000 tons. The workshop is...[Details]