SNLS401C February 2012 – September 2018 DS90C187
PRODUCTION DATA.
The DS90C187 has several power supply pins at 1.8 V. It is important that these pins all be connected and properly bypassed. Bypassing should consist of at least one 0.1μF capacitor placed on each pin, with an additional 4.7 μF - 22 μF capacitor placed on the PLL supply pin (VDDP). 0.01 μF capacitors are typically recommended for each pin. Additional filtering including ferrite beads may be necessary for noisy systems. It is recommended to place a 0 ohm resistor at the bypass capacitors that connect to each power pin to allow for additional filtering if needed. A large bulk capacitor is recommended at the point of power entry. This is typically in the 50 μF — 100 μF range.