EURO
QUARTZ
FEATURES
Provides up to -12dB reduction in system EMI
‘Drop-in’ replacement for standard clocks
No need to re-design printed circuit boards
Operates with 1.8 Volts supply voltage
Choice of modulation rate and spread
Miniature package: 7.0 mm x 5.0 mm x 1.4mm
18EQHM572 Low EMI Oscillator
Page 1 of 2
7 x 5 x 1.4mm SMD - Group 'F' (1.8 Volts)
SPECIFICATION
Model No:
Frequency Range:
EMI Reduction and Spread Types:
Modulation Carrier Frequency:
Output Logic:
Input Voltage:
Frequency Stability
Commercial (0~70°C):
OUTLINE & DIMENSIONS
18EQHM572
12.5MHz to 42.0MHz
CMOS
Vdd = +1.8 ±0.15VDC
±25ppm (Spec. code = ‘A’)
±50ppm (Spec. code = ‘B’)
±100ppm (Spec. code = ‘C’)
Industrial (-40~+85°C): ±25ppm (Spec. code = ‘D’)
±50ppm (Spec. code = ‘E’)
±100ppm (Spec. code = ‘F’)
Output Voltage HIGH ‘1’:
1.6V min., 1.85V max.
Output Voltage LOW ‘0’:
0.0V max., 0.2V max.
Rise/Fall Times:
2.5ns max.
Load:
15pF
Start-up Time:
2ms typical, 5ms max.
Stabilization Time:
40ms max.
Output Impedance:
30W typical
Output Slew Rate:
0.4 V/ns min.; 3.0V/ns max.
Current Consumption:
13MHz:
16MHz:
25MHz:
42MHz:
Duty Cycle:
Cyle to Cycle Jitter:
Ageing:
Pad 1 Option:
Packaging:
2.0mA typical
2.8mA typical
3.5mA typical
5.0mA typical
50%±10% (CL=15pF, 50%Vdd)
±100ps max.
±5ppm /year max at Ta=25°C
Output Enable/Disable. Output is
high impedance when taken low
Output enable time 100ms max.
EIA 16mm tape and reel, 1k per.
ENVIRONMENTAL SPECIFICATION
RoHS Compliance:
Moisture Sensitivity Level:
Second Level Interconnect:
Storage Temperature Range:
Humidity:
Fine Leak / Gross Leak:
Hermetic Seal:
Solderability:
Reflow:
Vibration:
Shock:
Resistance to Solvents:
Temperature Cycling:
ESD Rating:
RoHS compliant and Pb (lead) free
Level 1 (Infinite)
e4
-55° to +125°C
85% RH, 85°C for 48 hours
MIL-STD-883, meth. 1014, cond. A
MIL-STD-883, meth. 1014, cond. C
Leak Rate 2x10
-8
ATM-cm
3
/s max.
MIL-STD-2002F method 208E
260° for 10 seconds x2
MIL-STD-202F method 204, 35g,
50Hz to 2000Hz
MIL-STD-202F method 213B, test
condition: E, 1000g ½ sine wave
MIL-STD-202, Method 215
MIL-STD-883, Method 1010
>2000V (per MIL-STD-883,
method 3015)
Gold (0.3um min.) over nickel
(1.27um to 8.89um)
0.17 grams.
SPREAD TYPE & PERCENTAGE AND EMI REDUCTION RATES
Total %
Down
Spread (D)
-0.5% (D0.5)
-1% (D1)
-2% (D2)
Centre
Spread (C)
±0.25% (C0.25)
±0.5% (C0.5)
±1% (C1.0)
EMI
Reduction
Rate
-12dB (typ.)
-16dB (typ.)
-18dB (typ.)
0.5%
1%
2%
ABSOLUTE MAXIMUM RATINGS
Power Supply Voltage
Input Voltage
Output Voltage
Operation Junction Temp.
Output Current
-0.5V min., +2.5V max.
Vss-0.5V min., V
DD
+0.5V max.
Vss-0.5V min., V
DD
+0.5V max.
-40°C min., +125°C max.
-13mA min., +13mA max.
Pad Surface Finish:
Weight of the Device:
EUROQUARTZ LIMITED Blacknell Lane CREWKERNE Somerset UK TA18 7HE
Tel: +44 (0)1460 230000 Fax: +44 (0)1460 230001 info@euroquartz.co.uk www.euroquartz.co.uk
EURO
QUARTZ
18EQHM572 Low EMI Oscillator
Page 2 of 2
7 x 5 x 1.4mm SMD - Group 'F' (1.8 Volts)
PART NUMBER CONFIGURATION
‘T’ for Tristate
Series designation
Group ‘F’ Characteristics
SPREAD TYPE & PERCENTAGE
"D0.5"
-0.5%
Down Spread
-1%
-2%
±0.25%
Centre Spread
±0.5%
±0.1%
18EQHM57-BT-20.000F-C0.5
Frequency (MHz)
Frequency Stability Code
‘A’ to ‘F’. See specification
"D1"
"D2"
"C0.25"
"C0.5"
"C1.0
MODULATION TYPES - EXAMPLES
DESCRIPTION
18EQHM572 series low EMI oscillators can reduce system EMI by
-15dB. The oscillators are a ‘drop-in’ replacement for standard
oscillators. EMI reduction is achieved by the use of Spread Spectrum
Technology whereby the mode energy is spread over a wider
bandwidth. The modulation carrier frequency, operating in the kHz
region, makes the process transparent to the oscillator frequency.
There is a choice of modulation rates and spread to suit application
requirements.
INTRODUCTION
In electrical systems the principal cause of electro-magnetic
interference (EMI) is the system clock oscillator. Traditional methods of
'patching-up' systems with too high a level of EMI is to use ferrite
beads, filters, ground planes, metal shielding and similar costly
methods, However, the most efficient and economic method to reduce
EMI is to reduce it at source: replace the system clock ocillator with a
low EMI clock oscillator.
Compared with conventional clock oscillators, Spread Spectrum
(Dithered) Oscillators can reduce EMI by as much as -15dB. The part
is a 'drop-in' replacement for standard clock oscillators hence there is
no requirement to re-design existing PCBs.
SPREAD SPECTRUM TECHNOLOGY
Unlike a conventional clock oscillator, in a Spread Spectrum Clock
Oscillator the mode energy is spread over a wider bandwidth. This is
achieved by the frequency modulation technique. The controlled
modulation process may be applied to the 'down' side of the nominal
frequency (known as
DOWN SPREAD,)
or spread equally either side
of nominal (CENTRE
SPREAD).
Down Spread is preferred if over-
clocking would cause a problem to the system.
EUROQUARTZ LIMITED Blacknell Lane CREWKERNE Somerset UK TA18 7HE
Tel: +44 (0)1460 230000 Fax: +44 (0)1460 230001 info@euroquartz.co.uk www.euroquartz.co.uk
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