7.3.9 Under Voltage Lockout (UVLO)

The LMZ36002 device has an internal UVLO circuit which prevents the device from operating until the PV_IN voltage exceeds the UVLO threshold, (3.2 V (typ)). The device will begin switching and the output voltage will begin to rise once PV_IN exceeds the threshold, however PV_IN must be greater than (V_OUT/0.75) in order to for V_OUT to regulate at the set-point voltage.

Applications may require a higher UVLO threshold to prevent early turn-on, for sequencing requirements, or to prevent input current draw at lower input voltages. An external resistor divider can be added to the INH/UVLO pin to adjust the UVLO threshold higher. The external resistor divider can be configured as shown in Figure 31. Table 10 lists standard values for R_UVLO1 and R_UVLO2 to adjust the UVLO voltage higher.

Figure 31. Adjustable PVIN UVLO