ZHCSCD8C April 2014 – April 2019 LM46002
PRODUCTION DATA.
The undervoltage lockout (UVLO) is adjusted using the external voltage divider network of RENT and RENB. RENT is connected between the VIN pin and the EN pin of the LM46002. RENB is connected between the EN pin and the GND pin. The UVLO has two thresholds, one for power up when the input voltage is rising and one for power down or brown outs when the input voltage is falling. The following equation can be used to determine the VIN UVLO level.
The EN rising threshold (VENH) for LM46002 is set to be 2.1 V (typical). Choose the value of RENB to be 1 MΩ to minimize input current from the supply. If the desired VIN UVLO level is at 5 V, then the value of RENT can be calculated using Equation 25:
Equation 25 yields a value of 1.38 MΩ. The resulting falling UVLO threshold, equals 4.3 V, can be calculated by below equation, where EN falling threshold (VENL) is 1.8 V (typical).