ZHCSIW6L October 2000 – October 2018 LM4040-N , LM4040-N-Q1
PRODUCTION DATA.
The resistor RS must be selected such that current IR will remain in the operational region of the part for the entire VIN range and load current range. The two extremes to consider are VIN at its minimum, and the load at its maximum, where RS must be small enough for IR to remain above IRMIN. The other extreme is VIN at its maximum, and the load at its minimum, where RS must be large enough to maintain IR < IRMAX. For most designs, 0.1 mA ≤ IR ≤ 1 mA is a good starting point.
Use Equation 2 and Equation 3 to set RS between RS_MIN and RS_MAX.