SLVSCL5A June 2014 – November 2020 TPS2559
PRODUCTION DATA
Some applications require that an overcurrent condition disables the part momentarily during a fault condition and re-enables after a pre-set time. This auto-retry functionality can be implemented with an external resistor and capacitor. During a fault condition, FAULT pulls low EN. The part is disabled when EN is pulled below the turn-off threshold, and FAULT goes high impedance allowing C(RETRY) to begin charging. The part re-enables when the voltage on EN reaches the turn-on threshold. The part will continue to cycle in this manner until the fault condition is removed. The auto-retry cycling time is determined by the resistor/capacitor time constant, TPS2559 turn on time and FAULT deglitch time (see Figure 9-13).
Some applications require auto-retry functionality and the ability to enable/disable with an external logic signal. Figure 9-4 shows how an external logic signal can drive EN through R( FAULT) and maintain auto-retry functionality. The resistor, capacitor time constant determines the auto-retry time-out period.