MC33091A

The MC33091A is a HighSide TMOS Driver designed for use in harsh automotive switching applications requiring the capability of handling high voltages attributed to load and field dump transients, as well as reverse and double battery conditions. Few external components are required to drive a wide variety of NChannel TMOS devices. The MC33091A, driving an appropriate TMOS device, offers economical system solutions for highside switching large currents. The MC33091A has CMOS compatible input control, charge pump to drive the TMOS power transistor, basic fault detection circuit, VDS monitoring circuit used to detect a shorted TMOS load, and overcurrent protection timer with associated current squaring circuitry.

Short circuit protection is made possible by having a unique VDS voltage to current converter drive an externally programmable integrator circuit. MC33091A affords fast detection of a shorted load while allowing difficult loads, such as lamps having high inrush currents, additional time to turn on.

The Fault output of MC33091A is comprised of an open collector NPN transistor requiring a single pullup resistor for operation. A fault is reported whenever the MOSFET oncurrent exceeds an externally programmed set level.

The MC33091A is available in the plastic 8Pin DIP package as well as the plastic 8Pin surface mount package.
• Designed for Automotive HighSide Driver Applications
• Works with a Wide Variety of NChannel Power MOSFETs
• Drives Inductive Loads with No External Clamp Circuitry Required
• CMOS Logic Compatible Input Control
• OnBoard Charge Pump with No External Components Required
• Shorted Load Detection and Protection
• Forward Overvoltage and Reverse Battery Protection
• Load and Field Dump Protection
• Extended Operating Temperature Range
• Fault Output to Report a MOSFET Overcurrent Condition