MB39A214APFT-G-JNERE1 Datasheet, PDF (30/56 Pages) Fujitsu Component Limited. – 2ch DC/DC converter IC with PFM/ PWM synchronous rectification

MB39A214A
The over current limit value is affected by ILIM pin source current and over current detection offset voltage
in the IC except for the on resistance of the low-side FET and the inductor value. The variation of dropped
over current limit value caused by IC characteristics is calculated by the following formula.
ΔI_LIM =
2 ¯10^-7¯ R_LIM + 0.03
R_{ON_Sync}
ΔI_LIM
R_LIM
R_{ON_Sync}
: The variation of dropped over current limit value [A]
: Over current limitation value setting resistor [Ω]
: ON resistance of low-side FET [Ω]
Inductor current
Over current limit value ILIM
Dropped over current limit value due to _ILIM’
IC's characteristics
IO
ΔILIM
0
Time
The over current detection value needs to set a sufficient margin against the maximum load current.
30
DS405-00007-1v0-E