3EQHM57 Group ‘R’ Low EMI Oscillators 7 x 5 x 1.8mm SMD Spread Spectrum Clock Ocillator Page 1 of 2 Provides up to 15dB reduction in system EMI ‘Drop-in’ replacement for standard clocks Choice of modulation rate and spread Miniature package: 7.0 mm x 5.0 mm x 1.8mm In electrical systems the principal cause of electromagnetic 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 a standard clock oscillator hence there is no requirement to re-design existing PCBs. APPLICATIONS Printers, Multiple Function Printers (MPCs) Digital Copiers; PDAs Networking: LAN/WAN; Routers Storage Systems (CD-ROM, VCD, DVD, HDD) Scanners; Modems; Projectors Embedded Systems Musical Instruments Automotive: GPS car navigation systems LCD PC Monitors; LSD TVs ADSL; PCMCIA Still Digital Cameras (SDCs) DESCRIPTION EQHM57 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. 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 overclocking would cause a problem to the system. MODULATION TYPES - EXAMPLES Output amplitude (dB) vs. frequency span (MHz) EUROQUARTZ LIMITED Blacknell Lane CREWKERNE Somerset UK TA18 7HE Tel: +44 (0)1460 230000 Fax: +44 (0)1460 230001 [email protected] www.euroquartz.co.uk 3EQHM57 Group ‘R’ Low EMI Oscillators 7 x 5 x 1.8mm SMD Spread Spectrum Clock Ocillator Page 2 of 2 SPECIFICATION Model No: Frequency Range: Spread Types: EMI Reduction*: Modulation Carrier Frequency: Output Logic: Input Voltage: Frequency Stability*** Commercial (0~70°C): 3EQHM57 (Group ‘R’) 3.5MHz to 165.0MHz See table below -7dBc min. 100MHz at C0.25** -9dBc min. 100MHz at C0.5** -15dBc min. 100MHz at C1.5** With reference to dB level at no modulation. 6.9kHz min, 55.5kHz max. Frequency dependent Call for details CMOS Vdd = +3.3VDC ±5% OUTLINE & DIMENSIONS ±25ppm (Spec. code = ‘A’) ±50ppm (Spec. code = ‘B’) ±100ppm (Spec. code = ‘C’) Industrial (-40~+85°C): Output Voltage HIGH ‘1’: Output Voltage LOW ‘0’: Rise/fall Times: Load: Start-up Time: Storage Temperature: Current Consumption: 10 ~ 50MHz: 50 ~ 125MHz: Duty Cycle: Cyle to Cycle Jitter: Output Impedance: Static Discharge Voltage: Ageing: Packaging: Pad 1 Option: ±25ppm (Spec. code = ‘D’) ±50ppm (Spec. code = ‘E’) ±100ppm (Spec. code = ‘F’) 2.0V min., 3.2V typ. (90%Vdd) 0.8V max., 0.2V typ. (10%Vdd) 4ns max, (frequency dependant) 15pF 2ms typical, 5ms max. -65° to +150°C 10mA typical 18mA typical 50%±5% (CL=15pF, 50%Vdd) ±250ps typ. ±300ps max. 40 Ohms typical >2000V (per MIL STD 833) ±5ppm /year max at Ta=25°C EIA 16mm tape and reel, 1k per. Output Enable/Disable. Output is high impedance when taken low Output enable time 100ms max. Notes: * EMI reduction is applied to the entire frequency spectrum ** dBc: with respect to no modulation. Frequency and total % spread dependant. *** Frequency Stability parameter excludes modulation. ENVIRONMENTAL SPECIFICATION RoHS Compliance: Storage Temperature Range: Humidity: Hermetic Seal: Solderability: Reflow: Vibration: Shock: RoHS compliant and Pb (lead) free -55° to +125°C 85% RH, 85°C for 48 hours Leak Rate 2x10-8 ATM-cm3/s max. MIL-STD-2002F method 208E 260° for 10 seconds MIL-STD-202F method 204, 35g 50Hz to 2000Hz MIL-STD-202F method 213B, test condition: E, 1000g ½ sine wave AVAILABILITY OF SPREAD TYPES AND MODULATION RATES SPREAD TYPES and % MODULATION PART NUMBER CONFIGURATION DOWN SPREAD ‘T’ for Tristate Group ‘R’ Series designation 3EQHM57-BT-32.768R-C0.5 Frequency (MHz) D1.0 -1% D3.0 -3% CENTRE SPREAD C0.5 ±0.5% C1.5 ±1.5% Frequency Stability Code ‘A’ to ‘F’. See specification above EUROQUARTZ LIMITED Blacknell Lane CREWKERNE Somerset UK TA18 7HE Tel: +44 (0)1460 230000 Fax: +44 (0)1460 230001 [email protected] www.euroquartz.co.uk