PI6LC4840

PI6LC4840
Crystal to LVDS/LVCMOS Frequency Synthesizer
Features
Description
ÎÎ3.3V supply voltage ± 5%
The PI6LC4840 is an LC VCO based low phase noise design intended for the most demanding Ethernet applications. Common
Ethernet frequencies of 25MHz and 125MHz are supported,
with the 125Mhz having both LVDS and LVCMOS outputs for
maximum flexibility. One 25Mhz LVCMOS non-PLL output is
also available.
ÎÎThree banks of outputs:
àà Bank A: 3 25/50MHz pin selectable LVCMOS outputs
àà Bank B: 3 125MHz LVCMOS outputs
àà Bank C: 3 125MHz LVDS outputs
ÎÎ1 25MHz LVCMOS reference clock output (no PLL)
ÎÎ25MHz crystal input (SaRonix-eCera P/N FL2500029)
ÎÎLow 1ps max 12k-20MHz integrated phase noise design (for
125MHz CMOS and LVDS outputs)
ÎÎIndustrial temperature -40°C to 85°C
ÎÎPackage (Pb-free & Green)
àà 32-contact 5x5mm TQFN (ZH)
Block Diagram
Mode_1 = Pull-up
Mode_0,2 = Pull-down
3
Mode [2:0]
Control
Logic
LVCMOS
- 25MHz or 50MHz
÷20
or ÷10
SaRonix-eCera FL2500029
QA1
25MHz
X1
OSC
X2
Phase
Detector
VDDO_QA
QA0
QA2
VCO
CMOS - 125MHz
÷4
VDDO_QB
QB0
QB1
\M
QB2
LVDS 125MHz
QC1+
QC1-
÷4
MR
QC2+
QC2-
Pull-down
LVCMOS - 25MHz
10-0249
VDDO_QC
QC0+
QC0-
1
REF_Out
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PS9076
01/03/11
PI6LC4840
Crystal to LVDS/LVCMOS Frequency Synthesizer
GND
X2
X1
Mode_2
Mode_1
Mode_0
VDDA
GND
32
31
30
29
28
27
26
25
Pin Configuration (32-contact TQFN)
QC1-
QA0
5
20
QC1+
QA1
6
19
QC0-
QA2
7
18
QC0+
VDDO_QA
8
17
VDDO_QC
VDDO_QB
16
21
GND
4
15
GND
VDD
QC2+
14
22
MR
3
13
GND
GND
QC2-
12
23
QB2
2
11
REF_Out
QB1
VDDO_QC
10
24
QB0
1
9
VDDO_REF
Pinout Table
Pin Number
Pin Name
I/O Type
Description
1
VDDO_REF
Power
Reference Clock Output Buffer VDD
2
REF_Out
Output
25MHz LVCMOS output from fundamental oscillator core
3
GND
Power
Ground
4
GND
Power
Ground
5
QA0
Output
25 or 50MHz selectable LVCMOS output (see table 1)
6
QA1
Output
25 or 50MHz selectable LVCMOS output (see table 1)
7
QA2
Output
25 or 50MHz selectable LVCMOS output (see table 1)
8
VDDO_QA
Power
VDD Buffer Power for Bank A
9
VDDO_QB
Power
VDD Buffer Power for Bank B
10
QB0
Output
125MHz LVCMOS output
11
QB1
Output
125MHz LVCMOS output
12
QB2
Output
125MHz LVCMOS output
13
GND
Power
Ground
(Continued)
10-0249
2
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PS9076
01/03/11
PI6LC4840
Crystal to LVDS/LVCMOS Frequency Synthesizer
Pin Number
Pin Name
I/O Type
Description
14
MR
Input
Master Reset Pin. During Reset, LVCMOS outputs are pulled low, QCx+
outputs are pulled low, QCx- outputs are pulled high.
15
VDD
Power
VDD for core
16
GND
Power
Ground
17
VDDO_QC
Power
VDD Buffer Power for Bank C
18
QC0+
Output
125MHz LVDS Output
19
QC0-
Output
125MHz LVDS Output
20
QC1+
Output
125MHz LVDS Output
21
QC1-
Output
125MHz LVDS Output
22
QC2+
Output
125MHz LVDS Output
23
QC2-
Output
125MHz LVDS Output
24
VDDO_QC
Power
VDD Buffer Power for Bank C
25
GND
Power
GND
26
VDDA
Power
VDD for analog core
27
Mode_0
Input
Combination of output enable and frequency select functionality, see
Table 1. Internal pull-down.
28
Mode_1
Input
Combination of output enable and frequency select functionality, see
Table 1. Internal pull-up.
29
Mode_2
Input
Combination of output enable and frequency select functionality, see
Table 1. Internal pull-down.
30
X1
Input
Crystal Input
31
X2
Output
Crystal Output
32
GND
Power
GND
10-0249
3
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PS9076
01/03/11
PI6LC4840
Crystal to LVDS/LVCMOS Frequency Synthesizer
Function Table (Mode Pin)
Output Frequency (MHz)
Inputs
Bank A
Bank B
Bank C
Mode_2
Mode_1
Mode_0
QA0
QA1
QA2
QB0
QB1
QB2
QC0
QC1
QC2
0
0
0
25
-
-
-
-
-
125
-
-
0
0
1
25
-
-
125
-
-
125
-
-
0*
1*
0*
25
25
-
-
-
-
125
125
-
0
1
1
25
25
25
125
125
125
125
125
125
1
0
0
50
-
-
-
-
-
125
-
-
1
0
1
25
25
-
125
125
-
125
125
-
1
1
0
50
50
-
-
-
-
125
125
-
1
1
1
-
-
-
-
-
-
-
-
-
Notes:
- Outputs left in high impedance mode
* Default state
10-0249
4
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PS9076
01/03/11
PI6LC4840
Crystal to LVDS/LVCMOS Frequency Synthesizer
Maximum Ratings (Above which the useful life may be impaired. For user guidelines, not tested)
Note:
Stresses greater than those listed under MAXIMUM
RATINGS may cause permanent damage to the device. This
is a stress rating only and functional operation of the device
at these or any other conditions above those indicated in
the operational sections of this specification is not implied.
Exposure to absolute maximum rating conditions for
extended periods may affect reliability.
Storage temperature............................................... -65ºC to +155ºC
3.3V Analog Supply Voltage...................................... -0.5 to +4.6V
ESD Protection (HBM).......................................................... 2000V
Operating Conditions (VDD = VDDO_QA = VDDO_QB = VDDO_QC = VDDO_REF = 3.3V ±5%, TA = -40°C to 85°C)
Symbol
Parameters
VDD
VDDA
Conditions
Min.
Max.
3.3V Core Supply Voltage
3.135
3.465
3.3V for Analog
VDD - 0.5
VDD
3.135
3.465
–40
85
VDDO_REF, VDDO_QA,
Output Supply Voltage
VDDO_QC, VDDO_QB
TA
Ambient Temperature
IDD TOTAL
Sum of all IDD currents flowing into IC
100
IDD
Power Supply Current for VDD pin 15
15
IDDA
Analog Supply Current
50
IDDO_QA
Bank A LVCMOS Output Supply Current
IDDO_QB
Bank B LVCMOS Output Supply Current
IDDO_QC
LVDS Output Supply Current
25
IDDO_REF
Reference Supply Current
1
PDISS
Power Dissipation
0.35
10-0249
5
Outputs are unloaded
5
Units
V
°C
mA
10
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PS9076
W
01/03/11
PI6LC4840
Crystal to LVDS/LVCMOS Frequency Synthesizer
LVCMOS DC Electrical Characteristics (VDD = VDDO_QA = VDDO_QB = VDDO_QC = VDDO_REF = 3.3V ±5%, TA = -40°C
to 85°C)
Symbol
Parameters
VIH
Input High Voltage
2
VDD + 0.3
VIL
Input Low Voltage
-0.3
0.8
VOH
Output High Voltage
IOH = -12mA
VOL
Output Low Voltage
IOL = 12mA
0.5
Mode_1, VIN = VDD = 3.465V(1)
10
Input High Current
IIH
Conditions
Min.
Typ.
MR, Mode_2, Mode_0,
MR, Mode_2, Mode_0,
Input Low Current
VDD = 3.465V
Mode_1, VDD = 3.465V(1)
Units
V
2.6
150
VIN = VDD = 3.465V
IIL
Max.
µA
-5
-150
µA
IOZ
Tri-State output current
Rpu
Internal pull up resistance
55
kΩ
Rdn
Internal pull down resistance
55
kΩ
ZO
Output Impedance
38
Ω
CIN
Input Capacitance
COUT
Output Capacitance
1. With condition in Fig 2.
10
X1
5.5
X2
1.5
µA
pF
LVCMOS AC Characteristics (VDD = VDDO_QA = VDDO_QB = VDDO_QC = VDDO_REF = 3.3V ±5%, TA = -40°C to 85°C)
Symbol
Parameter
Tr/Tf
Output Rise/Fall time
TDC
Output Duty Cycle
Jphase
Integrated Phase Jitter
tSK(0)
Output-output skew
tj
Output period jitter
10-0249
Conditions
Min.
Typ.
Max.
20% to 80%, CL = 15pF
2
50W load
1.15
tDC = tH/tCY, tH = High Pulse Width,
tCY = Output Cycle Time, @ VDD/2
48
Units
ns
52
%
12kHz - 20MHz @125MHz
0.35
1
ps
12kHz - 1MHz @25MHz
0.30
1
ps
637kHz - 62.5MHz @125MHz
0.50
1
ps
Within a bank at the same supply and
with equal load
45
ps
Output Freq = 25MHz AND 50MHz
30
Output Freq = 125MHz
70
6
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PS9076
ps
01/03/11
PI6LC4840
Crystal to LVDS/LVCMOS Frequency Synthesizer
LVDS Output Characteristics (VDD = VDDO_QA = VDDO_QB = VDDO_QC = VDDO_REF = 3.3V ±5%, TA = -40°C to 85°C)
Symbol
Parameters
Condition
Min.
Trise / Tfall
Rise and Fall Time
20% to 80%, single-ended
TDC
Duty Cycle
Differential
Jphase
Integrated phase jitter
Tsk(o)
Output to Output skew
IOZ
Typ.
Max.
Units
145
360
ps
48
52
%
12KHz-20MHz @ 125MHz
637kHz - 62.5MHz @125MHz
(2)
0.45
1
0.45
1
Within a bank at the same supply
and with equal load
ps
35
ps
Tri-state Output Current
10
µA
TDIS
Output Disable Time
50
TEN
Output Enable Time
50
VOD
Differential Output Voltage
300
575
mV
VOS
Offset Voltage
1.325
1.575
V
PSRR
Power Supply Rejection Ratio
Modulation Power = -30dBm from
10k to 15M modulation freq.
ns
-50
dBc
2. Does not include 25MHz reference spur.
25MHz Crystal Characteristics (VDD = VDDO_QA = VDDO_QB = VDDO_QC = VDDO_REF = 3.3V ±5%, TA = -40°C to
85°C)
Parameters
Description
FREQ
Frequency
ESR
Equivalent Series Resistance
Cload
Load Capacitance
Cshunt
Shunt Capacitance
7
DRIVE
Drive Level
0.65
10-0249
Min
Typ
Max.
25
MHz
50
18
7
Units
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Ω
pF
mW
PS9076
01/03/11
PI6LC4840
Crystal to LVDS/LVCMOS Frequency Synthesizer
3.3V ±5%
3.3V ±5%
Power Supply
+ Float GND -
Z = 50Ω
VDD
VDDO_QC
VDDA
3.3V ±5%
Qx
SCOPE
VDD
50Ω
LVDS
nQx
VDDO_QA
VDDO_QC
50Ω
10Ω
VDDA
LVCMOS
15pF
GND
Figure 1. LVDS Output Load AC Test Circuit
Figure 2. LVCMOS Output Load AC Test Circuit
VDD
VDD
out
DC Input
LVDS
100Ω
out
VOD/∆ VOD
DC Input
50Ω
LVDS
50Ω
out
out
Figure 3. Differential Output Voltage Setup (VOD)
VOS/∆ VOS
Figure 4. OffsetVoltage Setup (VOS)
LVDS Buffer
Z o = 50-Ohm
0.1µF
Z o = 50-Ohm
0.1µF
Agilent E5052A/
Wavecrest
DTS-2079
Agilent 4402B
50Ω
Figure 5. LVDS Test Circuit for Phase Noise, Period Jitter, and PSRR
10-0249
8
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PS9076
01/03/11
PI6LC4840
Crystal to LVDS/LVCMOS Frequency Synthesizer
Application Notes
Crystal circuit connection
The following diagram shows PI6LC4840 crystal circuit connection with a parallel crystal. For the CL=18pF
crystal, it is suggested to use C1=27pF, C2=27pF. C1 and C2 can be adjusted to fine tune to the target ppm of
crystal oscillator according to different board layouts.
Crystal Oscillator Circuit
XTAL_IN
C1
27pF
SaRonix-eCera
GC250076B
Crystal�(CL�=�18pF)
XTAL_OUT
C2
27pF
10-0249
9
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PS9076
01/03/11
PI6LC4840
Crystal to LVDS/LVCMOS Frequency Synthesizer
Packaging Mechanical: 32-Contact TQFN (ZH)
1
DATE: 03/19/09
DESCRIPTION: 32-contact, Thin Fine Pitch Quad Flat No-lead (TQFN)
PACKAGE CODE: ZH (ZH32)
REVISION: A
DOCUMENT CONTROL #: PD-2070
09-0170
For latest package info, please check: http://www.pericom.com/products/packaging/mechanicals.php
Ordering Information
Ordering Code
Package Code
Package Type
PI6LC4840ZHE
ZH
Pb-free & Green, (TQFN)
1. Thermal characteristics can be found on the company web site at www.pericom.com/packaging/
2. E = Pb-free and Green
3. Adding an X suffix = Tape/Reel
Pericom Semiconductor Corporation • 1-800-435-2336
10-0249
10
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PS9076
01/03/11