As mentioned, the SG-9101 is a programmable oscillator with spread spectrum. What is a programmable oscillator (P-SPXO)? The blank oscillators can be programmed to the customer’s desired frequency which helps to reduce lead times for a timing product. How does it work? The basic principle of the Epson P-SPXO is using the Fractional-N PLL technology to synthesize any frequency from 0.67MHz to 170MHz with 1ppm resolution and features no frequency holes, unlike previous generation devices, which used an integer based PLL. The basic building blocks of the P-SPXO are as follows: Crystal oscillator (SPXO), Fractional-N PLL (Phase Lock Loop), Divider and Output buffer (typically CMOS output), and PLL Feedback Control block to set the desired frequency. For the SG-9101 series, a spread spectrum function block is added. For more details on the P-SPXO, please see “Part 1” of this series.