SLUAAN7 april   2023 TPS1211-Q1 , TPS4811-Q1


  1.   Abstract
  2.   Trademarks
  3. 1TPS1211-Q1 High Side Switch Controller Overview
  4. 2System Design Examples with Reverse Battery Protection
    1. 2.1 Design 1: Power Distribution Box
    2. 2.2 Design 2: Body Motors Load driving
    3. 2.3 Design 3: Heater Load Driving
      1. 2.3.1 Reverse Battery Protection with MOSFET OFF
      2. 2.3.2 Reverse Battery Protection with MOSFET ON
  5. 3Summary
  6. 4References


With evolving zonal architectures in automotive power distribution system, there is an increase in demand for High side switch controllers to drive most of the primary and secondary high current loads with external MOSFETs. These system designs include power distribution box and loads such as PTC heaters, body motors, and so on.

One of the key system requirement from car OEMs in 12-V automotive systems is to protect the DUT against the reverse battery connection. During maintenance of car battery or jump start of the vehicle, the battery can be connected in reverse polarity during reinstallation and this can cause damage to the connected subsystems, circuits, and components. Appropriate protection circuits need to be designed to make sure the DUT is protected and withstand the reverse battery condition. Based on the load type, the reverse battery protection can be implemented either with a back to back power switch or with a forward load switch topology.

This application note highlights how the TPS1211-Q1 high side switch controller can be used to achieve reverse battery protection for various high current body loads with various circuit configurations.