SLVAE51A November   2018  – October 2020 LM7310 , TPS2100 , TPS2101 , TPS2102 , TPS2103 , TPS2104 , TPS2105 , TPS2110 , TPS2111 , TPS2111A , TPS2112 , TPS2112A , TPS2113 , TPS2113A , TPS2114 , TPS2114A , TPS2115 , TPS2115A , TPS2120 , TPS2121 , TPS25947

 

  1.   Trademarks
  2. 1What is a Priority Power MUX?
  3. 2Control Method
    1. 2.1 Manual
    2. 2.2 Automatic
    3. 2.3 Both - Automatic + Manual Override
  4. 3Power MUX Topologies
    1. 3.1 Discrete
    2. 3.2 Semi-Integrated
    3. 3.3 Fully Integrated
  5. 4Switchover Method
    1. 4.1 Break-Before-Make vs. Diode Mode
    2. 4.2 What is Seamless Switchover?
    3. 4.3 Output Voltage Drop
    4. 4.4 Inrush Current
  6. 5Additional Protection
    1. 5.1 Overvoltage Protection
    2. 5.2 Overcurrent Protection
  7. 6Summary
  8. 7References
  9. 8Revision History

4.2 What is Seamless Switchover?

When switching between one supply to another, there are two possible outcomes:

  1. The output voltage drops below operating range, causing the loads to experience a systematic reset.
  2. The output voltage remains within operating range, causing uninterrupted operation. We will classify this type of outcome as seamless switchover.

If using a break-before-make power MUX, then switchover time is one key factor which will determine whether a seamless switchover will or will not occur. Faster switchover time will help achieve seamless switchover, at the expense of higher inrush current. This balance should be considered and power MUX solutions are available with a range of switchover times.

If using a diode-mode or make-before-break power MUX, then seamless switchover is often possible since worst-case output voltage drop will be approximately 0.4 V to 0.7 V (depending on the diode used).