The LTC490IS8 can handle clock frequencies up to 100MHz, but it's recommended to limit it to 50MHz for optimal performance and to avoid potential issues with clock skew and jitter.
To ensure proper termination of the differential clock inputs, use a 100Ω differential termination resistor between the clock inputs (CLK+ and CLK-) and a 0.01μF capacitor to ground on each clock input. This will help to reduce reflections and improve signal integrity.
For optimal performance, it's recommended to follow a star topology for the power supply connections, keep the analog and digital grounds separate, and use a solid ground plane to reduce noise and EMI. Also, keep the clock traces short and away from other signal traces to minimize clock skew and jitter.
To ensure proper power-up, it's recommended to sequence the power supplies in the following order: VCC, AVCC, and then DVCC. Also, make sure to power up the clock signal after the power supplies have stabilized.
The LTC490IS8 can drive up to 20mA of output current per channel, but it's recommended to limit the output current to 10mA per channel to ensure optimal performance and to avoid overheating.
LTC490IS8 datasheet
by Linear Technology
