LM3578A Datasheet | National Semiconductor

Description The LM1578A is a switching regulator which can easily be set up for such DC-to-DC voltage conversion circuits as the buck, boost, and inverting configurations. The LM1578A features a unique parator input stage which not only has separate pins for both the inverting and non-inverting inputs, but also provides an internal 1.0V reference to each input, thereby simplifying circuit design and p.c. board layout. The output can switch up to 750 m A and has output pins for its collector and emitter to promote design flexibility. An external current limit terminal may be referenced to either the ground or the Vin terminal, depending upon the application. In addition, the LM1578A has an on board oscillator, which sets the switching frequency with a single external capacitor from < 1 Hz to 100 k Hz (typical). The LM1578A is an improved version of the LM1578, offering higher maximum ratings for the total supply voltage and output transistor emitter and collector voltages. Features n n n n n n Inverting and non-inverting feedback inputs 1.0V reference at inputs Operates from supply voltages of 2V to 40V Output current up to 750 m A, saturation less than 0.9V Current limit and thermal shut down Duty cycle up to 90% Applications n Switching regulators in buck, boost, inverting, and single-ended transformer configurations n Motor speed control n Lamp flasher Functional Diagram DS008711-1 © 1998 National Semiconductor Corporation DS008711 .national. Absolute Maximum Ratings (Note 1) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Total Supply Voltage Collector Output to Ground Emitter Output to Ground (Note 2) Power Dissipation (Note 3) Output Current Storage Temperature Lead Temperature (soldering, 10 seconds) Maximum Junction Temperature 50V - 0.3V to +50V - 1V to +50V Internally limited 750 m A - 65˚C to +150˚C 260˚C 150˚C ESD Tolerance (Note 4) 2 k...