SNVSCW4A May 2025 – September 2025 TPS37100
PRODMIX
SENSE time delay (tCTS) is the minimum length of time required to count a fault on the SENSE pin as a valid fault and assert OUT A and OUT B. The time delay (tCTS) can be programmed by connecting a capacitor between CTS pin and GND.
The relationship between external capacitor CCTS_EXT (typ) and the time delay tCTS (typ) is given by Equation 8.
RCTS (typ) = is in kilo ohms (kΩ)
CCTS_EXT (typ) = is given in microfarads (μF)
tCTS (typ) = is given in milliseconds (ms)
The sense delay varies according to three variables: the external capacitor (CCTS_EXT), CTS pin internal resistance (RCTS) provided in Section 6.5, and the constant ( tCTS (CTS = Open)) provided in Section 6.5. The minimum and maximum variance due to the constant is show in Equation 9 and Equation 10:
The recommended maximum sense delay capacitor for the TPS3710x is 10μF as this makes sure there is enough time for the capacitor to fully discharge when a voltage fault occurs. Also, having a too large of a capacitor value can cause very slow charge up (rise times) and system noise can cause the internal circuit to trip unpredictably. This leads to a variation in time delay where the delay accuracy can be worse in the presence of system noise.
* Leakages on the capacitor can affect accuracy of sense time delay.