L9407F car voltage regulator circuit

The L9407F is a monolithic multifunction alternator voltage regulator intended for use in automotive application.
It includes the control section, the field power stage, fault diagnostic circuit which drives a warning lamp, and the protection against short circuits.
As you can see in this schematic circuit you’ll don’t need any external components to use this regulator in your car .

The alternator voltage is compared with a reference voltage in an amplifier, whose output determines the switching frequency of output power MOS whose current excites the coil of the alternator; as the regulators are a self-oscillating type this frequency depends on the whole system parameter set including the alternator characteristics.

Main features of this car voltage regulator are : Low side field driver, Thermal protection , Field short circuit protection , Protected diagnostic lamp driver, Protected high side relay driver , Complex diagnostics , Load response control , DFM output .