J Series Clock Oscillators Pletronics Inc. J Series Clock Oscillators are quartz crystal-controlled precision square wave generators. These clock oscillators provide low jitter and improved phase noise performance. The J series oscillators come with the Enable/Disable function on pad 1 and the Disable function, which includes low standby power mode. These clock oscillators employ fundamental and 3rd overtone crystals. The Pletronics HC77J oscillators offer HCSL output, while the LV44J, LV55J, and LV77J oscillators offer LVDS output. The PE77J oscillators provide PECL output.