The LM2940-N and LM2940C positive voltage regulators feature the ability to source 1 A of
output current with a dropout voltage of typically 0.5 V and a maximum of 1 V over the entire
temperature range. Furthermore, a quiescent current reduction circuit has been included which
reduces the ground current when the differential between the input voltage and the output voltage
exceeds approximately 3 V. The quiescent current with 1 A of output current and an input-output
differential of 5 V is therefore only 30 mA. Higher quiescent currents only exist when the
regulator is in the dropout mode (VIN − VOUT ≤ 3
V).
Designed also for vehicular applications, the LM2940-N and LM2940C and all regulated
circuitry are protected from reverse battery installations or 2-battery jumps. During line
transients, such as load dump when the input voltage can momentarily exceed the specified maximum
operating voltage, the regulator will automatically shut down to protect both the internal circuits
and the load. The LM2940-N and LM2940C cannot be harmed by temporary mirror-image insertion.
Familiar regulator features such as short circuit and thermal overload protection are also
provided.
