ZHCSTC5B October 2023 – June 2024 LM51772
PRODUCTION DATA
The LM51772 buck-boost control algorithm ensure a seamless transition between the different operating modes, fixed frequency operation, and power stage protection features. The internal state machine controls the current flow using three active switching states:
State I: Transistors Q1 and Q3 are conducting. Q2 and Q4 are not conducting (boost mode magnetization state).
State II: Transistors Q1 and Q4 are conducting. Q2 and Q3 are not conducting (boost demagnetization or buck magnetization state).
State III: Transistors Q2 and Q4 are conducting. Q1 and Q3 are not conducting (buck demagnetization state).
Switch | State I | State II | State III |
---|---|---|---|
Q1 | ON | ON | OFF |
Q2 | OFF | OFF | ON |
Q3 | ON | OFF | OFF |
Q4 | OFF | ON | ON |