JAJSR37A August 2023 – September 2023 UCC14340-Q1
PRODUCTION DATA
RLIM1 value is chosen by
∆ICOM_SOURCE=ICOM-VEE-IVDD-COM, when ICOM-VEE>IVDD-COM. Otherwise, ∆ICOM_SOURCE=0A
When the calculated RLIM1 value is higher than 3kΩ, we suggest to use a 3kΩ resistor for RLIM1. The reason is that the extra power loss saving with a >3kΩ resistor is very limited, and a maximum 3kΩ resistor is recommended to reserve enough sourcing capability through RLIM1 for transient event.
RLIM2 value is chosen by
where RLIM_MAX_L is the smallest value between RLIM_MAX_L1 and RLIM_MAX_L2 in the Single RLIM Resistor Selection Section, and 0.5V represents the diode forward voltage drop of DLIM.
When the calculated RLIM1 and RLIM2 values have large enough difference, the RDR improvement on efficiency will be significant. If RLIM1 and RLIM2 values are close, then single RLIM resistor can be considered to reduce the external components.
The power loss of RLIM1 can be derived as
where
The power loss of RLIM2 can be approximated as