SNVSCM3 June 2024 LM5171
PRODUCTION DATA
The DT/SD pin also serves as an emergency latched shutdown pin. During the operation the DT/SD pin is monitored by an internal circuit. The pin is normally regulated at 1.2V with a sourcing current limit of 300μA. Once the pin is externally pulled down below 0.5V for more than 2.5µs, the LM5171 shuts down and the state is latched until the UVLO is pulled below 1.25V to unlatch. Figure 6-19 shows an example of implementing the emergency latched shutdown function
When the LM5171 sets for adaptive dead time scheme, DT/SD pin needs to be pulled up to VDD. In order to implement the emergency latched shutdown control in this case, a 20kΩ limiting resistor must be placed across the VDD and DT/SD pin, as shown in Figure 6-20.