摘要 |
<p>A switching regulator includes a DC voltage source having a pair of DC output terminals, a switching transformer having a magnetic core, first and second primary windings and a secondary winding, a first switching transistor connected in series between the pair of DC output terminals through the first primary winding, a second switching transistor connected in series between the pair of DC output terminals through the first and second primary windings, and a rectifier circuit connected across the secondary winding. A pulse width modulator is provided to produce a PWM(pulse width modulated) control signal the duty of which is proportional to the voltage of the rectifier circuit, and the PWM. control signal is selectively supplied to one of the first and second switching transistors in response to the low or high circumstance of a load connected to the rectifier circuit. Further, a control circuit is provided so as not to excessively drive one of the first and second switching transistors during the switching operation thereof.</p> |