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%,
Let me tell you about the history of Android, review the style of the first generation of Android and compare it with the latest version 8.1. Find the interesting features and problems of Android, and...
I recently did a project that required me to extract the DC component from the collected analog signal. I tried a low-pass filter, but the effect was not ideal. There were still a lot of AC components...
Recalling the early spring of 41 years ago, as the first batch of college students after the ten-year catastrophe, I entered the university. After ten years of silence, the school from top to bottom a...
With the rapid development of wireless sensor networks, Zigbee technology, as a recently developed short-range wireless communication technology, is considered by the industry to be the most likely wi...
MOS tubes can be used for isolation, and diodes can also prevent backflow. So what is the difference between using MOS tubes for isolation and diodes for isolation, or can both be used?...
C1 and C2 are both constants. Just follow the arrows to replace the left-hand equation with the right-hand equation, which is the RX and RY solution formula, except that RX and RY are both known const...
1 Introduction
Precision time interval measurement is a key technology in industrial, national defense and power applications. Pulse counting is the most basic method in time interval measurem...[Details]
ELEXCON, hosted by UBM Creative, will be grandly opened at Shenzhen International Convention and Exhibition Center (Bao'an) from September 1 to 3, 2021! With nearly 30 years of experience in the elec...[Details]
1 Introduction When the vehicle is driving, the DYC (yaw torque) circuit is in working state. In case of emergency, the brakes need to be stepped on for control. At this time, the DYC circuit stops...[Details]
0 Introduction
With the development of power conversion technology, power MOSFET has been widely used in switching converters. For this reason, Silicon General Semiconductor Company of the Unit...[Details]
I have been in contact with STM32 for a while, and I have a simple introduction to it. However, due to some reasons, I am only writing this entry-level key-related program today, which is divided int...[Details]
The LTC4126 is a full-featured 7.5 mA wireless lithium-ion (Li-Ion) battery charger with a 1.2 V inductorless DC-DC converter designed for hearing aids, wireless headsets, and other space-constrained...[Details]
The MAX16008/MAX16009 are adjustable quad-window voltage monitors in a thin QFN package. These devices improve system reliability by monitoring multiple supply voltages and generating fault signals wh...[Details]
With the expansion of social electricity consumption, it is urgent to develop electricity detection and distribution in the direction of high precision, multi-function and intelligence by timely ...[Details]
Introduction: This article mainly introduces the PIC microcontroller software simulator PICSIM and its use to help you learn more about PIC microcontrollers. We know that microcontroller developmen...[Details]
In his report to the 19th National Congress of the Communist Party of China, General Secretary Xi Jinping pointed out that development is the foundation and key to solving all problems in my countr...[Details]
Test points are very important and familiar to testers. The accuracy of the test is closely related to the location of the test points. Incorrect test points will lead to incorrect test results, thus ...[Details]
TrendForce's Topology Research Institute pointed out today that as global consumer market demand gradually picks up, global automobile shipments are expected to reach 83.5 million units in 2021. In t...[Details]
Four-channel PWM 8 10-bit ADCs, 8 single-ended channels, 2 differential channels with programmable gain (1x, 10x, or 200x) Port A (PA7..PA0) Port A is used as the analog input of the A/D conv...[Details]
Previously, foreign media reported that the Delhi High Court in India ruled that ASUS had infringed the "Zen" trademark, so ASUS could not use the "ZenFone" name in India. The ruling will take ...[Details]
DC resistance tester is also called DC resistance measuring instrument, DC resistance meter, transformer DC resistance tester, DC resistance detector, DC digital bridge, etc. DC resistance test is ...[Details]