bq24030, bq24031, bq24032,
bq24032A, bq24035, bq24038, bq24039
www.ti.com
SLUS618C–AUGUST 2004–REVISED JUNE 2005
This short-circuit disable feature was implemented mainly for power up when inserting a battery. Because the
BAT input voltage rises much faster than the OUT voltage (Vout<Vbat-200 mV), with most any capacitive load on
the output, the part can get stuck in short-circuit mode. Placing a capacitor between the DPPM pin and ground
slows the VDPPM rise time, during power up, and delays the short-circuit protection. Too large a capacitance on
this pin (too much of a delay) could allow too-high currents if the output was shorted to ground. The
recommended capacitance is 1 nF to 10 nF. The VDPPM rise time is a function of the 100-µA DPPM current
source, the DPPM resistor, and the capacitor added.
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