Programmable FemtoClock
®
NG LVPECL/LVDS
Clock Generator with 6-Outputs
IDT8T49N006I
DATASHEET
General Description
The IDT8T49N006I is a six output Clock Generator with selectable
LVDS or LVPECL outputs. The IDT8T49N006I can generate any one
of four frequencies from a single crystal or reference clock. The four
frequencies are selected from the Frequency Selection Table (Table
3A) and are programmed via I
2
C interface. The four predefined
frequencies are selected in the user application by two frequency
selection pins. Note the desired programmed frequencies must be
used with the corresponding crystal or clock frequency as indicated
in Table 3A.
Excellent phase noise performance is maintained with IDT’s Fourth
Generation FemtoClock
®
NG PLL technology, which delivers
sub-400fs RMS phase jitter.
Features
•
•
•
•
•
•
•
•
•
•
•
Fourth Generation FemtoClock NG PLL technology
Six selectable LVPECL or LVDS outputs via I
2
C
CLK, nCLK input pair can accept the following differential input
levels: LVPECL, LVDS, HCSL
FemtoClock NG VCO Range: 1.91GHz - 2.5GHz
RMS phase jitter at 156.25MHz (12kHz - 20MHz): 228fs (typical)
RMS phase jitter at 156.25MHz (10kHz - 1MHz): 175fs (typical)
Full 2.5V or 3.3V power supply
I
2
C programming interface
PCI Express (2.5 Gb/S), Gen 2 (5 Gb/s) and Gen 3 (8 Gb/s) jitter
compliant
-40°C to 85°C ambient operating temperature
Lead-free (RoHS 6) packaging
Pin Assignment
V
CCO
nQ3
nQ4
nQ5
Q3
30 29 28 27 26 25 24 23 22 21
20
19
18
17
16
15
14
13
12
11
1 2
3 4
5 6 7
8
9 10
V
EE
SCLK
SDATA
V
EE
V
CCA
LOCK
V
EE
V
CC
CLK_SEL
V
EE
31
32
33
34
35
36
37
38
39
40
Q4
nc
nc
V
EE
Q5
FSEL1
V
CC
V
EE
ADDR_SEL
FSEL0
nCLK
CLK
V
EE
XTAL_OUT
XTAL_IN
nQ0
Q0
nc
nc
V
CCO
nQ1
IDT8T49N006I
40-Lead VFQFN
6mm x 6mm x 0.95mm package body
4.65mm x 4.65mm E-Pad
NL Package
Top View
IDT8T49N006A-dddNLGI REVISION A OCTOBER 22, 2013
1
©2014 Integrated Device Technology, Inc.
nQ2
V
EE
Q1
Q2
IDT8T49N006I Data Sheet
PROGRAMMABLE FEMTOCLOCK
®
NG LVPECL/LVDS CLOCK GENERATOR WITH 6-OUTPUTS
Block Diagram
LOCK
Q0
nQ0
Pulldown
CLK SEL
Q1
nQ1
XTAL_IN
XTAL_OUT
CLK
nCLK
PU/PD
Xtal
Osc
Pulldown
1
0
PS
÷P[1:0]
1
Phase
Detector
+
Charge
Pump
÷N[6:0]
FemtoClock
®
NG
VCO
0
Q2
nQ2
Q3
nQ3
Q4
nQ4
÷M [8:1]
Q5
VPP/FSEL
0
PROG_CLK/FSEL
1
SCLK
SDATA
ADDR_SEL
Pulldown
Pulldown
Pullup
Pullup
Pulldown
Divider,
Output Type
&
Output
Enable
Selection
nQ5
OUTPUT ENABLE
OUTPUT STYLE
6
6
IDT8T49N006A-dddNLGI REVISION A OCTOBER 22, 2013
2
©2014 Integrated Device Technology, Inc.
IDT8T49N006I Data Sheet
PROGRAMMABLE FEMTOCLOCK
®
NG LVPECL/LVDS CLOCK GENERATOR WITH 6-OUTPUTS
Table 1. Pin Descriptions
Number
1, 2, 29, 30
3, 4
5, 26
6, 7
8, 9
10, 13, 18,
21, 31, 34,
37, 40
11,
12
14
15
Name
nc
Q0, nQ0
V
CCO
Q1, nQ1
Q2, nQ2
V
EE
XTAL_IN
XTAL_OUT
CLK
nCLK
Unused
Output
Power
Output
Output
Power
Type
Description
Not connected
Differential output pair. LVPECL or LVDS interface levels.
Output supply pins.
Differential output pair. LVPECL or LVDS interface levels.
Differential output pair. LVPECL or LVDS interface levels.
Negative supply pins.
Crystal oscillator interface. XTAL_IN is the input, XTAL_OUT is the output.
Crystal frequency is selected from Table 3A.
Pulldown
Pullup/
Pulldown
Non-inverting differential clock input.
Inverting differential clock input. Internal resistor bias to V
CC
/2.
Frequency and configuration. Selects between one of four factory
programmable power-up default configurations. The four configurations can
have different PLL states, output frequencies, output styles and output
states. These default configurations can be overwritten after power-up via
I
2
C.LVCMOS/LVTTL interface levels.
00 = Configuration 0 (default)
01 = Configuration 1
10 = Configuration 2
11 = Configuration 3
I
2
C Address select pin. LVCMOS/LVTTL interface levels.
Core supply pins.
Differential output pair. LVPECL or LVDS interface levels.
Differential output pair. LVPECL or LVDS interface levels.
Differential output pair. LVPECL or LVDS interface levels.
Pullup
Pullup
I
2
C Clock Input. LVCMOS/LVTTL interface levels.
I
2
C Data Input. Input: LVCMOS/LVTTL interface levels. Output: Open
Drain.
Analog supply pin.
PLL Lock Indicator.
Pulldown
Input source select pin. LVCMOS/LVTTL interface levels.
0 = XTAL (default)
1 = CLK, nCLK
Input
Input
Input
16, 20
FSEL0,
FSEL1
Input
Pulldown
17
19, 38
22, 23
24, 25
27, 28
32
33
35
36
39
ADDR_SEL
V
CC
nQ5, Q5
nQ4, Q4
nQ3, Q3
SCLK
SDATA
V
CCA
LOCK
CLK_SEL
Input
Power
Output
Output
Output
Input
Input/Output
Power
Output
Input
Pulldown
NOTE:
Pullup
and
Pulldown
refer to internal input resistors. See Table 2,
Pin Characteristics,
for typical values.
Table 2. Pin Characteristics
Symbol
C
IN
R
PULLDOWN
R
PULLUP
Parameter
Input Capacitance
Input Pulldown Resistor
Input Pullup Resistor
Test Conditions
Minimum
Typical
3.5
51
51
Maximum
Units
pF
k
k
IDT8T49N006A-dddNLGI REVISION A OCTOBER 22, 2013
3
©2014 Integrated Device Technology, Inc.
IDT8T49N006I Data Sheet
PROGRAMMABLE FEMTOCLOCK
®
NG LVPECL/LVDS CLOCK GENERATOR WITH 6-OUTPUTS
Frequency Configuration
Table 3A. Frequency Configuration Examples
Output Frequencies
(MHz)
30.72
61.44
62.5
76.8
78.125
100
106.25
122.8
125
133.33
148.5
150
153.6
155.52
156.25
159.375
160
166.66
184.32
187.5
200
212.5
250
300
311.04
Input Frequency or
Crystal Frequency
(MHz)
30.72
30.72
25
30.72
25
25
26.5625
30.72
25
25
27
25
30.72
19.44
25
100
125
26.5625
20
25
30.72
61.44
25
25
26.5625
25
25
19.44
77.76
155.52
25
125
156.25
26.5625
25.78125
25
25
26.5625
30.72
30.72
122.88
153.6
19.44
25
30.72
Input Clock
Divider
P
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
5
1
1
1
1
1
1
1
1
1
1
1
1
2
1
2
5
1
2
1
1
1
1
1
2
5
1
1
1
Input Clock
Prescaler
PS
x2
x2
x2
x2
x2
x2
x2
x2
x2
x2
x2
x2
x2
x2
x2
x1
x2
x2
x2
x2
x2
x1
x1
x2
x2
x2
x2
x2
x1
x1
x2
x1
x2
x2
x1
x1
x2
x2
x2
x2
x1
x2
x2
x2
x2
Feedback
Divider
M
32
32
40
40
50
40
40
32
40
48
44
42
40
64
50
50
50
36
48
40
36
36
90
40
40
40
48
64
32
32
50
40
40
36
150
90
40
40
32
40
40
40
64
50
40
Output
Divider
N
64
32
32
32
32
20
20
16
16
18
16
14
16
16
16
16
16
12
12
12
12
12
12
10
10
8
8
8
8
8
8
8
8
6
6
6
5
5
4
4
4
4
4
4
2
VCO Frequency
(MHz)
1966.08
1966.08
2000
2457.6
2500
2000
2125
1966.08
2000
2400
2376
2100
2457.6
2488.32
2500
2500
2500
1912.5
1920
2000
2211.84
2211.84
2250
2000
2125
2000
2400
2488.32
2488.32
2488.32
2500
2500
2500
1912.5
1933.59375
2250
2000
2125
1966.08
2457.6
2457.6
2457.6
2488.32
2500
2457.6
312.5
318.75
322.265625
375
400
425
491.52
614.4
622.08
625
1228.88
NOTE: Each device supports 4 output frequencies (with related input or crystal value) as selected from this table Register Settings.
NOTE: XTAL operation: f
OUT
= f
REF
* PS * M / N; CLK, nCLK input operation: f
OUT
= (f
REF
/ P) * PS * M / N.
IDT8T49N006A-dddNLGI REVISION A OCTOBER 22, 2013
4
©2014 Integrated Device Technology, Inc.
IDT8T49N006I Data Sheet
PROGRAMMABLE FEMTOCLOCK
®
NG LVPECL/LVDS CLOCK GENERATOR WITH 6-OUTPUTS
Table 3B. I
2
C Register Map
Binary
Register
Address
00000
00001
00010
00011
00100
00101
00110
00111
01000
01001
01010
01011
01100
01101
01110
01111
10000
10001
10010
10011
10100
10101
10110
10111
Register Bit
D7
M0[8]
M1[8]
M2[8]
M3[8]
unused
unused
unused
unused
unused
unused
unused
unused
Register
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
D6
M0[7]
M1[7]
M2[7]
M3[7]
N0[6]
N1[6]
N2[6]
N3[6]
BYPASS0
BYPASS1
BYPASS2
BYPASS3
D5
M0[6]
M1[6]
M2[6]
M3[6]
N0[5]
N1[5]
N2[5]
N3[5]
PS0[1]
PS1[1]
PS2[1]
PS3[1]
D4
M0[5]
M1[5]
M2[5]
M3[5]
N0[4]
N1[4]
N2[4]
N3[4]
PS0[0]
PS1[0]
PS2[0]
PS3[0]
D3
M0[4]
M1[4]
M2[4]
M3[4]
N0[3]
N1[3]
N2[3]
N3[3]
P0[1]
P1[1]
P2[1]
P3[1]
D2
M0[3]
M1[3]
M2[3]
M3[3]
N0[2]
N1[2]
N2[2]
N3[2]
P0[0]
P1[0]
P2[0]
P3[0]
D1
M0[2]
M1[2]
M2[2]
M3[2]
N0[1]
N1[1]
N2[1]
N3[1]
CP0[1]
CP1[1]
CP2[1]
CP3[1]
D0
M0[1]
M1[1]
M2[1]
M3[1]
N0[0]
N1[0]
N2[0]
N3[0]
CP0[0]
CP1[0]
CP2[0]
CP3[0]
LVDS_SEL0[Q5] LVDS_SEL0[Q4] LVDS_SEL0[Q3] reserved LVDS_SEL0[Q2] LVDS_SEL0[Q1] LVDS_SEL0[Q0] reserved
LVDS_SEL1[Q5] LVDS_SEL1[Q4] LVDS_SEL1[Q3] reserved LVDS_SEL1[Q2] LVDS_SEL1[Q1] LVDS_SEL1[Q0] reserved
LVDS_SEL2[Q5] LVDS_SEL2[Q4] LVDS_SEL2[Q3] reserved LVDS_SEL2[Q2] LVDS_SEL2[Q1] LVDS_SEL2[Q0] reserved
LVDS_SEL3[Q5] LVDS_SEL3[Q4] LVDS_SEL3[Q3] reserved LVDS_SEL3[Q2] LVDS_SEL3[Q1] LVDS_SEL3[Q0] reserved
OE0[Q5]
OE1[Q5]
OE2[Q5]
OE3[Q5]
reserved
unused
unused
unused
OE0[Q4]
OE1[Q4]
OE2[Q4]
OE3[Q4]
reserved
unused
unused
unused
OE0[Q3]
OE1[Q3]
OE2[Q3]
OE3[Q3]
reserved
unused
unused
unused
reserved
reserved
reserved
reserved
reserved
unused
unused
unused
OE0[Q2]
OE1[Q2]
OE2[Q2]
OE3[Q2]
reserved
unused
unused
unused
OE0[Q1]
OE1[Q1]
OE2[Q1]
OE3[Q1]
reserved
unused
unused
unused
OE0[Q0]
OE1[Q0]
OE2[Q0]
OE3[Q0]
unused
unused
unused
unused
reserved
reserved
reserved
reserved
unused
unused
unused
unused
IDT8T49N006A-dddNLGI REVISION A OCTOBER 22, 2013
5
©2014 Integrated Device Technology, Inc.
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