The TPS92633-Q1 can support a single-LED-short detection by monitoring the output voltage when the output current is enabled and the DIAGEN input signal is high. The scale down output voltage V_(OUTx) of each channel is internally compared with a programmable reference voltage V_{(SLS_th_falling)} set by R_{(SLS_REF)} on the SLS_REF pin to detect a SLS fault. When the V_(OUTx) falls below V_{(SLS_th_falling)} longer than the deglitch time, the device asserts the fault and pulls low the FAULT pin. Combined with Figure 2-1, the V_{(SLS_th_falling)} can be calculated by Equation 5.

where:

• V_(IREF) = 1.235(Typical)
• R_(IREF) = 12.3kΩ recommended
• R_{(SLS_REF)} is in kΩ unit
• N_(OUT) = 4 (typical)
• N_(OUT) = 1 (typical)

More information is referred to the detailed description in theTPS92633-Q1 Three-Channel Automotive High-Side LED Driver with Thermal Sharing and Off-Board Binning.

The TPS92633-Q1 can support the maximum output current of 450mA when all channels are tied together, the V_{(SLS_th_falling)} is adjusted according to the number of LED and the total output current. Generally, to achieve the single-LED-short detection, the V_{(SLS_th_rising)} needs to be kept within the bounds following relationship from Equation 6.

where:

• N is the number of LED in the LED string.
• V_{F_max} is the maximum forward voltage of the LED used at the given current.
• V_{F_min} is the minimum forward voltage of the LED used at the given current.