SNVSBI5A July 2019 – September 2019 TPS3870-Q1
PRODUCTION DATA.
The TPS3870-Q1 features three options for setting the reset delay (tD): connecting a capacitor to the CT pin, connecting a pull-up resistor to VDD, and leaving the CT pin unconnected. Figure 21 shows a schematic drawing of all three options. To determine which option is connected to the CT pin, an internal state machine controls the internal pulldown device and measures the pin voltage. This sequence of events takes 450 μs to determine which timing option is used. Every time the voltage on the SENSE line enters the valid window (VSENSE < VIT+(OV) -VHYS, the state machine determines the CT option.