SLVAFO4 august   2023 TPS61299

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Overview
  5. 2Load Connected to Input Voltage
    1. 2.1 Body Diode Pass (TPS61288)
    2. 2.2 Force Pass Through (TPS61253)
    3. 2.3 Bypass (TPS61291)
    4. 2.4 Summary
  6. 3Load Disconnected to Input Voltage
    1. 3.1 Synchronous HSD FET With Switchable Body Diode (TPS61299)
    2. 3.2 Extra ISO FET to Cut-Off Leakage Path
  7. 4Summary
  8. 5References

Abstract

In conventional non-synchronous boost converters, the load is connected to the input voltage through the inductor and rectifier diode during shutdown. In some always-on systems in which the load needs to be powered by the input voltage when boost is disabled, some strategies like pass through and bypass are proposed to reduce voltage drop and power loss in the diode.

In some occasions, the load does not need to be powered by the boost converter and the system is sensitive to power loss during shutdown. True disconnection function is proposed to satisfy such a demand.

This application note introduces different control strategies and topologies to implement the features of pass through, bypass, and true load disconnection during shutdown.