SLUSDQ4 April 2019 BQ79606A-Q1
PRODUCTION DATA.
While not required for cable lengths less than 2m and BCI performance of less than 200mA, longer cable lengths, or abnormally noisy applications may require the use of a common-mode choke filter. Capacitive isolation plus choke has better noise immunity than capacitor only. For 1.7m cable and according to ISO 11452-4 BCI spec, the capacitor only isolation can pass up to 200mA BCI noise and if a choke is added, a 300mA BCI noise can be handled. For these applications, use an automotive grade from 100uH to 500 μH common-mode filter minimum for proper operation. To achieve the best performance in noisy environments, use dual common-mode filters (470 μH). The recommended impedance of the choke is at least 1KΩ from 1MHz to 100MHz and above 300Ω for higher frequencies