MB39A132QN-G-ERE1 Datasheet, PDF (20/56 Pages) Fujitsu Component Limited. – ASSP For Power Management Applications (Rechargeable Battery) Synchronous Rectification DC/DC Converter IC for Charging Li-ion Battery

MB39A132
(4) Overcurrent detection block (Over Current Det.)
When this block detects that the potential difference between the +INC2 pin (pin 12) and the -INC2 pin (pin
13) exceeds 0.2 V (Typ), and excessive current flows in the charging direction due to a sudden change of
load, this block will determine that overcurrent occurs, and sets the CS pin (pin 19) to "L" level and the ON
duty to 0%. Afterward, when the overcurrent ceases to exist, the soft-start operation is started.
0.2(V)
Overcurrent detection value : Ioc det(A) =
RS(Ω)
Charge current and overcurrent detection value by RS value (example)
RS
ADJ2
Io
OCDet
20 mΩ 0.5 V to 4.4 V 0.85 A to 8.65 A
10 A
15 mΩ 0.5 V to 4.4 V 1.13 A to 11.5 A
13 A
(5) Overtemperature detection
The circuit protects an IC from heat destruction. If the temperature at the joint reaches +150 °C, the circuit
set OUT1 (pin 30) and OUT2 (pin 27) pins to "L", and stops voltage output.
In addition, if the temperature at the joint drops to +125 °C, the voltage output restarts again.
When designing a DC/DC power supply system, do not exceed the absolute maximum ratings of this IC in
order to prevent overtemperature protection from being activated.
20
DS04–27265–3E