Vishay Intertechnology announces a pair of clock oscillators featuring a 3.3 VDC input and a 1 to 70 MHz frequency range. The XO 543 and XO 523 feature TTL and HCMOS compatibility, and a tri-state feature that allows the output to be placed into a high-impedance state. The devices are designed to provide clock signal sources for digital ICs and microprocessors in low-power applications such as telecommunications equipment and portable peripherals. Typical input currents for the devices range from 10 to 30 mA with rise and fall times of 10 ns max. A ñ100 ppm frequency stability is standard, with ñ25 ppm and ñ50 ppm optional.