SST Oscillators Also Help Suppress EMI May 2003 Issue Published Date: May 01, 2003
In addition to their timing capabilities, the EQ-HM series of spread spectrum technology (SST) oscillators is also said to provide a low-cost means of reducing EMI radiation in electronic systems. The oscillators can deliver between 10 and 16 dB of EMI suppression at source and are drop-in replacements for standard clock oscillators spanning an 8 MHz to 165 MHz frequency range. Typical of the SST oscillators is the EQ-HM42 series. The new timing devices meet both FCC and European EMC Directive EMI requirements and come in 5V and 3.3V versions with CMOS logic output. Other specs include "high" output voltage of 4.5V and 2.4V minimum, respectively, "low" output voltage of 0.4V maximum, and output load of 10 LSTTL gates or 15 pF. The oscillators deliver a 45/55 duty cycle, 5 ns (max.) rise/fall times, and current consumption of 15 mA to 45 mA. Both commercial and industrial temperature range devices are available. The EQ-HM42 oscillators come housed in a standard, 2.5-mm high, four-pad SMT package.
