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%,
How to get started with embedded systems? I just happened to see this article, so I turned to it here, hoping to solve some of the questions of novices. -----------------------------------------------...
Abstract: When there are many Chinese characters to be displayed, the Chinese character encoding in the single-chip microcomputer system is very cumbersome. This paper introduces a method of directly ...
The data is sent to USART1->DR, but the output of USART1->DR is all 0? ? I don’t have an experimental board, and I want to simulate USART1 reception and output. [/size][/font][/b][/align][align=left][...
[size=4]1. Note: Try not to put the file in a directory containing Chinese characters, otherwise it may fail. [/size] [size=4]2. IAR has two modes, one is virtual, that is, simulation debugging, and t...
Regarding the routines provided by TI, there are two paragraphs of CODE, but I don’t quite understand the first paragraph--------------------------- -------------------------------------------------- ...
Dual-mode inverters can operate both in conjunction with the grid and independently. These inverters can inject excess energy from renewable energy and storage devices into the grid, and withdraw p...[Details]
1. Equipment Overview
Shell-and-tube heat exchangers are a common heat exchange device used in chemical evaporation and heating equipment. Currently, the tubesheets of shell-and-tube heat exch...[Details]
summary
There are multiple approaches to making industrial systems more intelligent, including applying artificial intelligence (AI) technology at the edge and in the cloud to sensor...[Details]
1 Introduction
In the mid-1960s, American scientist Maas conducted extensive experimental research on the charging process of open-cell batteries and proposed an acceptable charging curve for ...[Details]
Since its invention in the mid-1940s, the microwave oven has evolved from a humble beginning to commercial use, entering homes in the 1960s and rapidly gaining popularity. Its basic functionality a...[Details]
introduction
According to the China Fire Statistics Yearbook, electrical fires accounted for more than 30% of fire accidents in the past decade, and the trend is increasing year by year. They ...[Details]
1. Multi-channel DAC technology bottleneck
Currently,
the development of multi-channel DAC technology focuses on two core challenges.
First, industrial applications urgently ...[Details]
1. Fault phenomenon and cause analysis
1. During the operation of the equipment, the expansion sleeve is subjected to a large torque, and the mating surfaces of the shaft and the sleeve move...[Details]
In the field of communications power supplies, AC/DC rectifier power supplies are called primary power supplies or basic power supplies, while DC/DC converters are called secondary power supplies. ...[Details]
Shenzhen Baowei Power Supply high frequency pure sine wave power, communication inverter power supply has two communication interfaces, RS232 and R485 interfaces, their functions and characteristic...[Details]
A pure sine wave inverter has a good output waveform with very low distortion, and its output waveform is essentially the same as the AC waveform of the mains power grid. In fact, the AC power prov...[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]
With growing environmental awareness, the continuous improvement of three-electric technology and the increasing deployment of infrastructure such as charging stations, the electrification of new e...[Details]
Smartphones can be incredibly unintelligent. For example, consider an office full of people, each absorbed in their work. Suddenly, the silence is broken by a burst of loud pop music. A colleague's...[Details]