LT1910 is a very popular high side driver that allows the use of low cost N-channel power MOSFETs for high side switching applications. It contains a 750kHz charge pump to fully enhance an N-channel MOSFET switch with no external components. The LT1910 has been specifically designed for harsh operating environments like those found in industrial, avionics and automotive. The ability of the driver to stay on indefinite period of time (independently of the load) makes this device ideal for automotive applications. It often employs this diver as load switch and positive rail disconnect for motors, electronic modules and dashboard equipment.
The circuit presenter here demonstrates functionality of LT1910 as low frequency PWM. This type of application is used in DC and step motor control. Voltage source, Vpmw, generates input pulses and the LT1910 correspondingly turns on and off the load, Rload. To demonstrate short circuit protection capability of this driver a Short Circuit Block has been included. This block turns on switch S1 for period 0.2 sec during which the voltage source, Vin, stays disconnected from the load to, reducing stress on the supply lines.
LT1910 datasheet describes in details multiple applications of this high side driver for capacitive and inductive loads and latch-off configuration. LT1161 is a quad version of this device.
Tools & Simulations
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.