EMI Reduction Spread Spectrum Clock Oscillators
3HM572 Series Group “R”
The most efficient way to reduce EMI (Electromagnetic Interference) is to reduce it from its
principle source – the clock oscillator. Mercury 3HM572, an integrated clock module
composed of a spread spectrum clock and a quartz crystal, reduces EMI by 9 dB or more
while providing the clock speed needed for the system. It is a drop-in replacement for
standard 5x7 mm non-SSC clocks, no need to change the board or the solder pad layout.
The 3HM572 series (1.4 mm height) replaces the 3HM57 series (1.8 mm height). They are
identical products, with the only difference being the package heights. The 3HM57 is obsolete.
Please refer to Mercury
PCN-111004 “Change HM57 to HM572” .
MERCURY
Since 1973
Applications:
◘
Printers; Multiple function printers (MPCs)
◘
Digital copiers; PDAs
◘
Networking; LAN / WAN; Routers
◘
Storage systems
(CD-ROM,
VCD, DVD & HDD)
◘
Scanner; Modems; Projectors
◘
Hand-held ID Readers
◘
Embedded systems; Electrical Musical Instrument
◘
Automotive; GPS Car Navigation Systems
◘
LCD PC Monitors / LCD TVs
◘
ADSL; PCMCIA
◘
Still Digital Cameras (SDCs)
◘
Medical Devices
Spread Spectrum Clock (SSC):
Unlike the conventional clock, the mode
energy of a spread spectrum clock is
spread (distributed) over a wider
bandwidth between two pre-defined
frequency boundaries by the
frequency
modulation
technique. The modulation
carrier frequency is in the KHz range
which makes the modulation process
transparent to the oscillator frequency.
This controlled modulation process can
be on all of one side of the nominal
frequency (down
spread),
which is
preferred if system over-clocking is a
concern, or 50% up and 50% down
(center
spread).
Modulation Types
DOWN or CENTER spread
Down spread “D”.
“D1” as an example
Center spread “C”.
“C0.5” as an example
Output amplitude (dB) vs frequency span (MHz)
dB
EMI reduction
Conventional
Clock
dB
EMI reduction
Conventional
Clock
Spread
spectrum
clock
dB
fo - (fo*1%)
fc
Frequency
dB
fo - (fo*0.5%)
fo=fc
fo + (fo*0.5%)
32.768 MHz non-SSC vs SSC at Center Spread 1.5%:
No modulation
-9.9 dB
Center spread
1.5% (C1.5)
-23.0 dB
13.1 dB
reduction
Taiwan: TEL (886)-2-2406-2779, FAX (886)-2-2496-0769, e-mail:
sales-tw@mercury-crystal.com
U.S.A.: TEL (1)-909-466-0427, FAX (1)-909-466-0762, e-mail:
sales-us@mercury-crystal.com
MERCURY
Page 1 of 5
Oct. 18, 2011 Rev. 0
MERCURY
www.mercury-crystal.com
EMI Reduction Spread Spectrum Clock Oscillators
3HM572 Series Group “R”
General Specifications:
at Ta=+25°C, C
L
=15 pF
Mercury Model
Frequency Range
Spread Type
Spread Percentage
(tolerance : ±2% of the total %)
EMI Reduction
(EMI reduction is applied to the
entire spectrum)
Modulation Carrier Frequency
(Dither rate)
Output Logic
Input Voltage (V
DD
)
Frequency Stability
(exclude modulation)
Output Voltage “High”; “1”
Output Voltage “Low”; “0”
Rise Time / Fall Time
Load
Start-up Time
Stabilization Time
Current Consumption
Duty Cycle
Cycle-to-cycle Jitter
Output Impedance
Static Discharge Voltage
Aging
Packaging
Pin 1 Function
3HM572
Group “R”
5.0 ~160.0 MHz
Total %
Down Spread
(D)
Center Spread
(C)
1%
-1%
(D1)
±0.5
(C0.5)
3%
-3%
(D3)
±1.5
(C1.5)
-9 dB min. 100 MHz at C0.5
-15 dB min. 100 MHz at C1.5
With respect to the dB level when no modulation.
6.9 KHz min.; 55.5 KHz max.;
Frequency dependent. Call for details.
CMOS Square Wave
V
DD
= +3.3 V D.C. ±5%
Commercial
(-10°C to +70°C):
“A”: ±25 ppm ; “B’: ±50 ppm; “C”:±100 ppm
Industrial
(-40°C to +85°C):
“D”: ±25 ppm ; “E’: ±50 ppm; “F”:±100 ppm
2.0 V min.; 3.2 V typical (at 90%
V
DD
)
MERCURY
Since 1973
V
DD
)
4 n sec. max. (10%
V
DD
↔
90%
V
DD
)
0.8 V max. ; 0.2 V typical (at 10%
15 pF
2 ms typical; 5 ms max.
2 ms max.
10.0 MHz: 7 mA; 32.768 MHz: 8 mA
75.0 MHz: 17 mA; 125 MHz: 18 mA
50%±5%. ( C
L
=15 pF
;
at 50%
V
DD
)
±250 ps typical; ±300 ps max.
40 ohms typical
>2000 V (per MIL-STD-883, method 3015)
±5 ppm per year max.; Ta=+25°C
16 mm tape and reel. 1000 pcs per reel
Output is high impedance when taken low.
Output enable /disable time: 100 ns max.
Environmental Performance Specifications
RoHS Status
Moisture Sensitivity Level
Second Level Interconnect
Storage temp. range
Humidity
Fine Leak / Gross Leak
Solderability
Reflow
Vibration
Shock
Resistance to Solvent
Temperature Cycling
ESD Rating
Pad Surface Finish
Weight of the Device
RoHS compliant, Pb (lead) free in accordance with EU Directive 2002/95/EC
6/6 (2002/95/EC) and WEEE (2002/96/EC)
Level 1 (infinite) according to IPC/JEDEC J-STD-020D.1
e4
-55 to +125°C
85% RH, 85°C, 48 hours
MIL-Std-883, method 1014, condition A / MIL-Std-883, method 1014, condition C
MIL-STD-202F method 208E
260°C for 10 sec. 2X.
MIL-STD-202F method 204, 35G, 50 to 2000 Hz
MIL-STD-202F method 213B, test condi. E, 1000GG ½ sine wave
MIL-STD-202, method 215
MIL-STD-883, method 1010
>2000 V (per MIL-STD-883, method 3015)
Gold (0.3 um min.) over nickel (1.27 um to 8.89 um)
155 mg per unit typical
MERCURY
Page 2 of 5
Oct. 18. 2011
Rev. 0
EMI Reduction Spread Spectrum Clock Oscillators
3HM572 Series Group “R”
Part Number Format and Example:
}:
User to specify.
Format: 3HM572-{
stability code}
T-{
nominal frequency}
R-{
spread type
}{
spread
%}
Example: 3HM572-BT-32.768R-C0.5
Stability Code
“A”
Commercial
“B”
(-10°C ~+70°C)
“C”
“D”
Industrial
“E”
(-40°C ~+85°C)
“F”
Spread Type and Percentage
“D1”
Down Spread
“D3”
“C0.5”
Center Spread
“C1.5”
MERCURY
Since 1973
{
Option on pin 1
“T”
Tri-state. Default
“ “ (blank) No connection
±25 ppm
±50 ppm
±100 ppm
±25 ppm
±50 ppm
±100 ppm
-1%
-3%
±0.5%
±1.5%
Description of the example:
+3.3V HM572 series 5x7 mm spread spectrum clock, frequency stability is ±50 ppm
over -10°C to +70°C, Tri-state on pin 1, 32.768 MHz, center spread ±0.5%
HM572 Package Dimensions and Recommended Solder Pad Layout
7.00±0.15
Pin 1
(Rounded)
Pin 2
Pin 3
Pin 4:
2.2[0.086]
5.00±0.15
Tri-state
Ground
Output
Supply Voltage
2.0[0.079]
0.6
1.4
Group R is also available in these packages:
HM53:
5x3.2x1.2 mm 4 pad ceramic SMDs
HM43:
9.6x11.4x3.0 mm FR4 base leadless SMDs
0.1
5.08[0.200]
5.08[0.200]
Recommended Solder Reflow Profile
(from
IPC/JEDEC J-STD-020D.1)
MERCURY
Page 3 of 5
1.8[0.071]
1.25
R0
.7
R0
.2
Oct. 18. 2011
Rev. 0
EMI Reduction Spread Spectrum Clock Oscillators
3HM572 Series Group “R”
Profile Feature
Sn-Pb Eutectic Assembly
Preheat/Soak
- Temperature min. (Ts min.)
100⁰C
- Temperature max. (Ts max.)
150⁰C
- Time (ts) (Ts min. to Ts max.)
60 to 120 seconds
Ramp-up rate (T
L
to Tp)
3⁰C / sec. max.
Liquidous temperature (T
L
)
183⁰C
Time (t
L
) maintained above T
L
60 to 150 seconds
Peak package body temperature (Tp)
235⁰C
Time (Tp) within 5⁰C of the classification temperature Tc 10 to 30 seconds
Ramp-down rate (Tp to T
L
)
6⁰C / second max.
6 minutes max.
Time 25⁰C to peak temperature
All temperatures refer to topside of the package, measured on the package body surface.
Pb-free Assembly
150⁰C
200⁰C
60 to 180 seconds
3⁰C / sec. max.
217⁰C
60 to 150 seconds
260⁰C
20 to 40 seconds
6⁰C / second max.
8 minutes max.
MERCURY
Since 1973
Block Diagram
OE
Oscillator
VDD
VSS
PLL
SSC Clock
÷
Spread Spectrum
Modulator (KHz)
Product Marking
Frequency stability code: “A”~”F”
“3” for +3.3V V
DD
“HM572” product prefix
Frequency in MHz
Example: 100.000
Pin #1 indicator
“T”:Tri-state on pin 1
Group “R
Spread type and percentage. Example: C1.5
Week number of the month. “1”~”5”
Month.“A”: Jan.~”L”: Dec.
Year. “1”: 2011, “2”: 2012, etc
3HM572 xT-R
xxx.xxx xx.x
MEC x x x
Product Support and Related Document
Technical note:
TN-020 “Low EMI Spread Spectrum Clock Oscillators”
Product Change Notice:
PCN-111004 “Change HM57 to HM572”
MERCURY
Page 4 of 5
Oct. 18. 2011
Rev. 0
EMI Reduction Spread Spectrum Clock Oscillators
3HM572 Series Group “R”
MERCURY
Since 1973
EMI Reduction of 3HM572 100 MHz at C0.25, C0.5 and C1.5. The Main Mode and the Modulated Spectra.
TS305B Spectrum analyzer Waveform @SSC=OFF
0
-10
-20
-30
[dBm]
No modulation
C0.25 (center spread ±0.25%)
TS305B Spectrum analyzer Waveform @SSC=+/-0.25%
0
-10
-20
-30
[dBm]
Modulation carrier
frequency is 34.87 KHz
C0.25 is for information only.
Not an orderable option.
-3.33dBm
-11.19dBm
-40
-50
-60
-70
-80
-90
-100
96
97
98
99
100
101
102
103
104
Frequency[MHz]
-40
-50
-60
-70
-80
-90
-100
96
97
98
99
100
101
102
103
104
Frequency[MHz]
-3.33dBm
-11.19dBm
7.86 dB reduction
TS305B Spectrum analyzer Waveform @SSC=+/-0.5%
C0.5 (center spread ±0.5%)
0
-10
-20
-30
[dBm]
TS305B
C1.5
Spectrum analyzer Waveform @SSC=+/-1.5%
(center spread ±1.5%)
0
-12.98dBm
-10
-20
-30
[dBm]
-18.54dBm
-40
-50
-60
-70
-80
-90
-100
96
97
98
99
100
101
102
103
104
Frequency[MHz]
-40
-50
-60
-70
-80
-90
-100
96
97
98
99
100
101
102
103
104
Frequency[MHz]
-12.98dBm
9.68 dB reduction
-18.54dBm
15.21 dB reduction
TS305B Spectrum Analyzer Waveform @SSC=OFF
0
-10
-20
-30
[dBm]
No modulation
-10.04
-20.15
TS305B Spectrum Analyzer Waveform @SSC=+/-0.25%
C0.25 (center spread ±0.25%)
0
-10
-11.21
-20.19
-33.37
-37.72
-38.87
-48.97
-3.21
-24.25
-25.40
-35.04
-20
-30
[dBm]
-40
-50
-60
-70
-80
-90
-100
0
100 200 300 400 500 600 700 800 900 1000 1100 1200
Frequency[MHz]
-40
-50
-60
-70
-80
-90
-100
0
100 200 300 400 500 600 700 800 900 1000 1100 1200
Frequency[MHz]
TS305B Spectrum Analyzer Waveform @SSC=+/-0.5%
C0.5 (center spread ±0.5%)
0
-10
-20
-30
[dBm]
[dBm]
TS305B Spectrum Analyzer Waveform @SSC=+/-1.5%
0
C1.5 (center spread ±1.5%)
-12.80
-24.45
-36.75
-41.23
-10
-20
-30
-42.47
-51.40
-19.46
-29.09
-41.22
-46.35
-48.47
-58.77
-40
-50
-60
-70
-80
-90
-100
0
-40
-50
-60
-70
-80
-90
-100
100 200 300 400 500 600 700 800 900 1000 1100 1200
Frequency[MHz]
0
100 200 300 400 500 600 700 800 900 1000 1100 1200
Frequency[MHz]
MERCURY
Page 5 of 5
Oct. 18. 2011
Rev. 0
Microchip MCU
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