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

4.3 Output Voltage Drop

With a break-before-make power mux, there will be a period of time (tSW, switchover time) where the input supply is not providing power to the output. This will cause the output voltage to decay based on the following equations:

GUID-734AC24E-C670-44EE-A184-21E729AD27A8-low.jpgFigure 4-1 Voltage Dip on Output During Switchover Time
Equation 1. VOUT,MIN = VSW - VDIP
Equation 2. VDIP = tSW × (IOUT / COUT)

Therefore a faster switchover time, tSW will result in a smaller voltage dip on the output, VDIP.