SLDS272 September 2024 DRV81620-Q1
ADVANCE INFORMATION
Sometimes one or more of the outputs of the device need to drive capacitive loads such as lamps or electronic loads. In such scenarios, after the switch is turned ON, the inrush current can reach the overload current threshold, thereby latching the channel OFF. In normal operation the device waits until the microcontroller sends an SPI command to clear the latches (CLRx bits) allowing the channel to turn ON again. Usually this delay is too long to start up the capacitive load.
If the corresponding bit BIMx is set to 1b, in case the channel reaches the overload current threshold or the overtemperature threshold and latches OFF, it restarts automatically after a time tINRUSH, allowing the load to go out of the inrush phase. A time diagram is shown in Figure 7-10. As shown, the counter starts when the channel is switched ON. Every channel switch OFF (independently from the entity controlling the channel) resets the bit BIMx to 0b.
While BIMx bits are set to 1b, ERRx bits may be also set to 1b but this doesn’t latch the channel OFF.
An internal timer sets the BIMx bits back to 0b after 40 ms (parameter tBIM) to prevent an excessive thermal stress to the channel, especially in case of short circuit at the output.
The device allows a per-channel selection of Bulb Inrush Mode (BIM) in order to be flexible without any reliability risk.