ZHCSN39A February 2020 – November 2021 LM61480 , LM61495 , LM62460
PRODUCTION DATA
The LM6x4xx uses VCC as its internal power supply. VCC is, in turn, powered from VIN or BIAS. Once the LM6x4xx is active, power comes from VIN if BIAS is less than approximately 3.1 V. Power comes from BIAS if BIAS is more than 3.1 V. VCC is typically 3 V to 3.3 V under most conditions, but can be lower if VIN is very low. To prevent unsafe operation, VCC has a UVLO that prevents switching if the internal voltage is too low. See VCC_UVLO and VCC_UVLO_HYST in Section 7.5. During start-up, VCC momentarily exceeds its normal operating voltage until VCC_UVLO is exceeded, then drops to its normal operating voltage. These UVLO values, when combined with the dropout of the LDO when only powering the LM6x4xx, are used to derive minimum VIN_OPERATE and VIN_OP_H.