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
C/SPI Control Registers...................................................................................................................................................... 30
9.1. Register Address: 0x00. DCO Frequency Control Least Significant Word (LSW) .................................................... 30
9.2. Register Address: 0x01. OE Control, DCO Frequency Control Most Significant Word (MSW) ................................. 31
9.3. Register Address: 0x02. DCO PULL RANGE CONTROL ........................................................................................ 32
9.4. Register Address: 0x03. Frac-N PLL Integer Value and Frac-N PLL Fraction MSW ................................................ 33
9.6. Register Address: 0x05. PostDiv, Driver Control ...................................................................................................... 34
9.7. Register Address: 0x06. mDriver, Driver Control ...................................................................................................... 35
10 I
2
C Operation ........................................................................................................................................................................ 36
10.1. I
2
C protocol ............................................................................................................................................................... 36
10.2. I
2
C Timing Specification ............................................................................................................................................ 39
10.3. I
2
C Device Address Modes ....................................................................................................................................... 40
Dimensions and Patterns ........................................................................................................................................................... 47
Additional Information ................................................................................................................................................................ 48
Revision History ......................................................................................................................................................................... 49
Rev 1.00
Page 3 of 49
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SiT3542
340 to 725 MHz Endura™ Series I
2
C/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.
340.000001
340.000001
Typ.
–
–
Max.
725.000000
500.000000
Unit
MHz
MHz
Condition
LVDS and LVPECL output driver, factory or user
programmable, accurate to 6 decimal places
HCSL output driver, 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
Frequency Stability
F_stab
-20
-20
-25
-50
First Year Aging
F_1y
–
–
–
–
–
±1
–
–
–
+20
+20
+25
+50
–
ppm
ppm
ppm
ppm
ppm
1
st
-year aging at 25°C
Temperature Range
Operating Temperature Range
T_use
-20
-40
-40
+70
+85
+105
°C
°C
°C
Extended Commercial
Industrial
Extended Industrial. Available only for I
2
C operation, not SPI.
Rugged Characteristics
Acceleration (g) sensitivity,
Gamma Vector
Supply Voltage
F_g
–
–
0.1
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
ppb/g
Low sensitivity grade; total gamma over 3 axes; 15 Hz to
2 kHz; MIL-PRF-55310, computed per section 4.8.18.3.1
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
9.1
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
–
–
11.8
µs
Rev 1.00
Page 4 of 49
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SiT3542
340 to 725 MHz Endura™ Series I
2
C/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
–
–
–
–
–
–
0.10
–
94
63
–
30
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
–
0.22
0.075
0.23
0.09
1
0.260
0.085
0.325
0.095
1.6
ps
ps
ps
ps
ps
f = 622.08 MHz, Integration bandwidth = 12 kHz to 20 MHz,
all Vdd levels
f = 622.08, IEEE802.3-2005 10 GbE jitter mask integration
bandwidth = 1.875 MHz to 20 MHz, all Vdd levels
f = 622.08 MHz, Integration bandwidth = 12 kHz to 20 MHz,
all Vdd levels
f = 622.08, IEEE802.3-2005 10 GbE jitter mask integration
bandwidth = 1.875 MHz to 20 MHz, all Vdd levels
f = 622.08 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
89
67
–
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
–
–
–
–
–
–
340
530
50
1.375
50
460
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
0.060
0.21
0.070
1
0.255
0.070
0.320
0.80
1.6
ps
ps
ps
ps
ps
f = 622.08 MHz, Integration bandwidth = 12 kHz to 20 MHz,
all Vdd levels
f = 622.08 MHz, IEEE802.3-2005 10 GbE jitter mask
integration bandwidth = 1.875 MHz to 20 MHz, all Vdd levels
f = 622.08 MHz, Integration bandwidth = 12 kHz to 20 MHz,
all Vdd levels
f = 622.08 MHz, IEEE802.3-2005 10 GbE jitter mask
integration bandwidth = 1.875 MHz to 20 MHz, all Vdd levels
f = 622.08 MHz, Vdd = 3.3V or 2.5V
mV
mV
V
mV
ps
f = 622.08 MHz. See
Figure 7
See
Figure 7
See
Figure 7
See
Figure 7
Measured with 2 pF capacitive loading to GND, 20% to 80%,
利用OC门虽然可以实现线与的功能,但外接电阻R p 的选择要受到一定的限制而不能取得太小,因此影响了工作速度。同时它省去了有源负载,使得带负载能力下降。为保持推拉式输出级的优点,还能作线与联接,人们又开发了一种三态与非门,它的输出除了具有一般与非门的两种状态,即输出电阻较小的高、低电平状态外,还具有高输出电阻的第三状态,称为高阻态,又称为禁止态。 一个简单的TSL门的电路如上图所示。其中C...[详细]