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%,
Can the active crystal oscillator be divided? The crystal oscillator of the clock chip DS1302 needs to be connected to 32768HZ! There are none for sale!! I have to divide the frequency!...
Chapter 1 Overview
Section 1 Introduction to the Hardware Development Process
§ 1.1.1 Basic process of hardware development
The basic process of hardware development:
1. Clarify the overall hardware r...
Choose VHDL or Verilog HDL? Before you choose, it is necessary to briefly introduce their general names: Hardware Description Language HDL (Hardware Describe Language) HDL Overview With the developmen...
The manual says that the sampling frequency of 430F149 can be up to 200K. Is it configured by setting SHTO and SHT1? In addition, the pulse sampling mode is triggered by TIMEA-OUT1? I want to achieve ...
The PRU includes two independent real-time RISC cores (only about 40 instructions, for logic, arithmetic and flow control, etc.), which can be software-programmed to implement peripherals, access GPIO...
Inspired by zhaojun_xf's article,
LPCXpresso -- Don't you feel anything about it? (A comprehensive and in-depth experience) https://bbs.eeworld.com.cn/thread-108322-1-1.html
I just attended NXP's Beij...
introduction
With the continuous optimization of surface mount technology (SMT) and the rapid development of chip component manufacturing technology, the application of chip mounters in the el...[Details]
1. Introduction
Automobile pollution is one of the most important issues that people are most concerned about and need to solve urgently. As an important method for detecting automobile exhau...[Details]
No matter which processor you are learning, the first thing you need to understand is the registers and working mode of the processor.
ARM has 37 registers, including 31 general registers and ...[Details]
The Mobile Industry Processor Interface (MIPI) Alliance is an organization responsible for promoting the standardization of software and hardware in mobile devices. It has released the D-PHY specif...[Details]
This paper establishes a fuel cell engine test platform based on the NI integrated hardware and software environment. This platform can realize the test and control of fuel cell engines and their a...[Details]
1 Introduction
Ultrasonic waves have strong directivity, slow energy consumption, and can propagate over long distances in a medium, so they are used for distance measurement. Ultrasonic detec...[Details]
1. What is temperature?
Heat is a type of molecular motion. The hotter an object is, the faster its molecules move. Absolute zero is defined as the temperature at which all molecular motion ...[Details]
1 Introduction
In recent years, there have been many major advances in the production technology and processes of automotive headlights, which have greatly improved the performance of automoti...[Details]
1 Introduction
There have been many studies on the detection and protection of power grid short circuit and line fault. The short circuit, overload and overvoltage protectors on the market have ...[Details]
Different initialization between C8051F and 80C51 series microcontrollers
In the past 30 years, major electronic component manufacturers in the world have launched their own unique single-chip...[Details]
Single-chip microcomputers are widely used because of their small size, powerful functions and low price. This article introduces the method of designing a micro electronic piano using the AT89C51 sin...[Details]
Since AC mains power may experience power outages, voltage sags and surges, continuous undervoltage and overvoltage, and frequency fluctuations during supply, these factors will affect the continuous ...[Details]
1. Overview
At present, an information revolution is in the ascendant around the world, led by microelectronics, computers and communication technologies, and centered on information technolog...[Details]
1 Introduction
With the improvement of people's quality of life, lamps are no longer just basic indoor lighting tools, but also a kind of practical art for architectural decoration. When ther...[Details]