JAJSHN5B june 2019 – february 2023 TPS1HB35-Q1
PRODUCTION DATA
When IOUT reaches the current limit threshold, ICL, the channel will switch off immediately. The ICL value will vary with slew rate and a fast current increase that occurs during a powered-on short circuit can temporarily go above the specified ICL value. In the case that the device remains enabled and limits IOUT, the thermal shutdown protection feature can be triggered due to the high amount of power dissipation in the device. When the switch is in the FAULT state, it will output an output current ISNSFH on the SNS pin . In addition, fault indication will occur when the switch is actively limiting current (applicable to version C).
During a short-circuit event, the device will hit the ICL value that is listed in the Electrical Characteristics table (for the given device version and RILIM) and then turn the output off or regulate the output current to protect the device. The device will register a short-circuit event when the output current exceeds ICL, however, the measured maximum current can exceed the ICL value due to the TPS1HB35-Q1 deglitch filter and turn-off time. This deglitch time is defined at 3 µs, so use the test setup described in the AEC-Q100-012 Short Circuit Reliability section, and take 3 µs before the peak value as the ICL. The device is assured to protect itself during a short-circuit event over the nominal supple voltage range (as defined in the Electrical Characteristics table) at 125°C.
The current threshold is defined for version C is different than version A or B. For version C, the current through the device continues to flow until the device hits relative thermal shutdown (TREL). For different VBBs the slope of the current will change. Therefore, the intersection point of where each of the slopes for the different VBB values is determined as the current threshold, ILIM, as shown in Figure 9-2. This behavior allows for the TPS1HB35C-Q1 to be able to charge up a 270-µF capacitor without shutting off due to hitting the current limit as versions A and B would.