| 摘要 |
A DC-DC converter comprises a primary converter circuit (P) with primary switches (Q1, Q2), a primary switch conduction control unit (SCP) controlling the primary switches (Q1, Q2), a secondary converter circuit (S) with rectifying switches (Q3, Q4), a secondary switch conduction control unit (SCS) controlling the rectifying switches (Q3, Q4), and a signal transformer (TR2) that isolates the secondary control unit (SCS) from the primary control unit (SCP). The signal transformer (TR2) is connected via first rectifying diodes (D1, D2) to supply voltage input terminals of the secondary control unit (SCS) to provide supply voltage to the same, and via second rectifying diodes (D3, D4) to a pulse detecting circuit that is adapted to remove the supply voltage from the secondary control unit (SCS) when control pulses to the secondary control unit (SCS) vanish. |
