The LT3081 complements the LT308x family of current-source reference LDOs. Compared to the LT3080, the LT3081 features single-supply operation, has a higher nominal reference current of 50µA, making it less sensitive to board leakage and possible V_OUT degradation. Also, for a given V_OUT, the SET resistor value is smaller, resulting in a lower impedance node and making it more difficult to couple stray signals in V_SET. Further, the LT3081 has higher output current, more extensive protection including reverse protection, wider SOA, programmable current limit, no C_IN or C_OUT requirement, plus it has an output current monitor and temperature monitor. Comparing the LT3081’s architecture against the popular 1.5A LT1963A, both use a PNP power transistor. However, the LT3081’s current reference uses one resistor to set V_OUT whereas the LT1963A uses a traditional voltage reference requiring two resistors to set V_OUT. In terms of advantages over LT1963A, the LT3081 has wider SOA, no C_OUT required, output operation below 1.2V and down to 0V, lower minimum input voltage, can be directly paralleled without an op amp, and has lower output voltage noise. Alternatively, the LT1963A has low dropout capability and shutdown.