Dallas ships all-silicon frequency synthesizer

The DS1085 is touted by Dallas Semiconductor Corp. as the industry's first frequency synthesizer IC that can accurately generate dual synchronous output frequencies over the full 8kHz to 133MHz range, without the use of external crystals, resistors, or other discrete components.

Positioned as a low-cost alternative to crystal-based clock synthesizers, the device can be used as a processor peripheral device through a 2-wire interface for dynamic frequency changes, or it can be preprogrammed to be used as a fixed-frequency oscillator.

The internal master clock is programmable over the full scale of 66MHz to 133MHz. This, in combination with two programmable 3-bit prescalers and a 1-to-1,025 divider, is claimed to allow more than 10 million possible output frequencies.

Dual control pins may be set to act as power-down or output-enable controls, depending on the application.

All synthesizer settings are stored in EEPROM, providing default conditions during power-up. The DS1085 has >1 percent absolute frequency accuracy. A 5V (DS1085) and 3V (DS1085L) version are both available in an 8-pin SOP casing.