This is a implementation for buck boost configuration. This circuit is control by LM2575. This is the figure of the circuit.
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In some applications it is desirable to keep the regulator off until the input voltage reaches a certain threshold. These circuits keep the regulator off until the input voltage reaches a predetermined level.
VTH ≈ VZ1 + 2VBE (Q1)
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In some applications it is desirable to keep the regulator off until the input voltage reaches a certain threshold. These circuits keep the regulator off until the input voltage reaches a predetermined level.
VTH ≈ VZ1 + 2VBE (Q1)