Ordering Information .................................................................................................................................................................... 2
7.1. User Programming Interface ..................................................................................................................................... 19
7.2. Start-up output frequency and signaling types .......................................................................................................... 19
8.1. Any-frequency function ............................................................................................................................................. 20
9 I C/SPI Control Registers...................................................................................................................................................... 29
9.1. Register Address: 0x00. DCO Frequency Control Least Significant Word (LSW) .................................................... 29
9.2. Register Address: 0x01. OE Control, DCO Frequency Control Most Significant Word (MSW) ................................. 30
9.3. Register Address: 0x02. DCO PULL RANGE CONTROL ........................................................................................ 31
9.4. Register Address: 0x03. Flac-N PLL Integer Value and Flac-N PLL Fraction MSW ................................................. 32
9.6. Register Address: 0x05. PostDiv, Driver Control ...................................................................................................... 33
9.7. Register Address: 0x06. mDriver, Driver Control ...................................................................................................... 34
2
10 I C Operation ........................................................................................................................................................................ 35
2
10.1. I C protocol ............................................................................................................................................................... 35
2
10.2. I C Timing Specification ............................................................................................................................................ 37
2
10.3. I C Device Address Modes ....................................................................................................................................... 38
Dimensions and Patterns ........................................................................................................................................................... 45
Additional Information ................................................................................................................................................................ 46
Revision History ......................................................................................................................................................................... 47
Rev 0.991
Page 3 of 47
www.sitime.com
SiT3521
1 to 340 MHz Elite™ I
2
C/SPI Programmable Oscillator
1 Electrical Characteristics
PRELIMINARY
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
Frequency Stability
Symbol
f
F_stab
Min.
1
-10
-20
-25
-50
First Year Aging
Operating Temperature Range
F_1y
T_use
–
-20
-40
-40
Supply Voltage
Vdd
2.97
2.7
2.52
2.25
Input Voltage High
Input Voltage Low
Input Pull-up Impedance
Duty Cycle
Start-up Time
Output Enable/Disable Time –
Hardware control via OE pin
Output Enable/Disable Time –
Software control via I
2
C/SPI
VIH
VIL
Z_in
DC
T_start
T_oe_hw
70%
–
–
45
–
–
Typ.
–
–
–
–
–
±1
–
–
–
3.3
3.0
2.8
2.5
–
–
100
–
–
–
Max.
340
+10
+20
+25
+50
–
+70
+85
+105
Supply Voltage
3.63
3.3
3.08
2.75
–
30%
–
55
3.0
3.8
V
V
V
V
Vdd
Vdd
kΩ
%
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
OE pin
OE pin
OE pin, logic high or logic low
Unit
MHz
ppm
ppm
ppm
ppm
ppm
°C
°C
°C
1 -year aging at 25°C
Extended Commercial
Industrial
Extended Industrial. Available only for I C operation, not SPI.
2
st
Condition
Factory or user programmable, accurate to 6 decimal places
Inclusive of initial tolerance, operating temperature, rated
power supply voltage and load variations.
Frequency Range
Frequency Stability
Temperature Range
Input Characteristics – OE Pin
Output Characteristics
Startup and Output Enable/Disable Timing
T_oe_sw
–
–
6.5
µs
Rev 0.991
Page 4 of 47
www.sitime.com
SiT3521
1 to 340 MHz Elite™ I
2
C/SPI Programmable Oscillator
Table 2. Electrical Characteristics – LVPECL Specific
Parameter
Symbol
Min.
Typ.
Max.
Unit
PRELIMINARY
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 = 3.3V or 2.5V
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 = 3.3V or 2.5V
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 = 3.3V or 2.5V
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 = 3.3V or 2.5V
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 experimented with the CRC16 routine of NXP810 and found that LPC_CRC->WR_DATA_WORD = 0x3534; if (LPC_CRC->SUM != 0xD7D6) { /* §°LED */ while (1) { LPC_GPIO_PORT->PIN0 &= ~LED; /* LED */ myDelay(100)...
Hello, thank you for reading this post. This position is located in Shanghai, in a company with a very promising future in the field of LED drivers. The company is now developing rapidly and has a lar...
I use stc12c5a60s2, the camera can send back hexadecimal data, but the crystal oscillator I use is 12M, and the SD card is sector storage. Will the camera overwrite the buffer data before the custom b...
Foreign-funded company, work location: Chengdu - a city you don't want to leave once you come here. Hardware Engineer (10 people): Job Description: 1. Design, development and debugging of digital and ...
The product I bought two days ago arrived. There is nothing useful in it. Only the box can be used. I suggest a summary of the entire POS machine to avoid detours [url]https://item.taobao.com/item.htm...
About the problem of notifying the application through events after SSDT is HOOKed. There should be no problem in HOOKing SSDT. The HOOKed information can be displayed in your own function through Dbg...
The most significant feature of IPS panels is that both electrodes are located on the same surface, unlike other LCD panels, which have electrodes arranged on top and bottom surfaces in a three-dim...[Details]
Multi-touch mobile phone
Multi-touch is a system that can respond to multiple touches on the screen at the same time. Multi-touch phones are divided into capacitive and resistive types. Capaci...[Details]
Today's security industry has entered the era of massive networking. Many enterprises, especially financial institutions, have established multi-level video surveillance networking platforms. Lever...[Details]
According to foreign media reports, researchers at the University of Surrey have developed an artificial intelligence system that can accurately locate the location of equipment in densely populate...[Details]
The automotive industry in 2025 is undergoing a thorough intelligent reshuffle.
Geely wants to make changes in the field of AI cockpits: in the future, there will be no traditional smart...[Details]
1 Source of creativity
With the further development of electronic technology, electronic pets have gradually entered people's family life. At present, there are two main categories of relative...[Details]
Have you ever heard stories about "crazy appliances"? Think of microwaves that turn on automatically or ovens that preheat without any human input? With radios and electromagnetic interfaces ubiqui...[Details]
With the development of science, the use of variable frequency technology is becoming more and more widespread, and it is used in both industrial equipment and household appliances. Inverter air co...[Details]
Reflow soldering is one of the most commonly used methods in electronics manufacturing, allowing for the soldering of large numbers of components in a relatively short time. However, any experience...[Details]
HTTP is the abbreviation of Hypertext Transfer Protocol. It is an application protocol based on TCP/IP communication protocol used to transmit HTML and image files. It is an application-level objec...[Details]
MQTT Ethernet I/O modules primarily collect I/O port information and transmit data over the network. In addition to being a TCP server, Ethernet I/O modules can also function as TCP clients. Furthe...[Details]
The driving mode is not unfamiliar to vehicles. According to the driving mode of the vehicle, there are front-wheel drive, rear-wheel drive and even four-wheel drive. Four-wheel drive is a major se...[Details]
Shanghai, China, August 21, 2025 –
Toshiba Electronic Devices & Storage Corporation (“Toshiba”) today announced the launch of the TLX9161T
, an automotive photorelay in a compact SO12L-T pa...[Details]
"I want to ask why there are so many manufacturers making mobile phone CPUs, but only Intel and AMD make computer CPUs?"
The progress of domestic PC CPU production has disappointed many ...[Details]
introduction
With the development of the information superhighway and the internet, broadcast television has become increasingly widespread worldwide. Television information has emerged in var...[Details]
NXP MCU
京公网安备 11010802033920号
EEWORLD
