Power supply circuit with a self-oscillating blocking oscillator
AssigneeSiemens Aktiengesellschaft
InventorRoman Haas
Life of this patent
Estimating the term…
Abstract
A power supply circuit is disclosed with a self-oscillating blocking oscillator. A switching transistor and a transformer connecting to a supply voltage produce a DC output voltage which can be obtained from the transformer via a rectifier arrangement. A regulating circuit in a control circuit of the switching transistor is provided which controls the switching transistor as a function of a comparison voltage which is drawn from a primary circuit of the transformer. An integration member connected parallel to the supply voltage produces a periodic, sawtooth-shaped signal which corresponds to the current in the primary circuit and with which the regulating circuit is driven so as to trigger the switching transistor.
Claims4
A self-sustaining blocking oscillator power supply circuit, comprising:
- a primary circuit formed of a DC supply voltage connected to a switching transistor through a primary of a transformer;
- rectifying means connected to a secondary of the transformer for producing a DC output voltage;
- regulating circuit means connecting to a control input of the switching transistor for controlling the switching transistor as a function of a comparison voltage derived from the primary circuit;
- an integration means connected parallel to the DC supply voltage for producing a periodic, approximately sawtooth-shaped signal which substantially corresponds to a current flowing in the primary circuit at the primary of the transformer, the sawtooth-shaped signal driving the regulating circuit means for triggering of the switching transistor;
- and the integration means comprising an RC member connected to be discharged via a switch means for synchronous operation with the switching transistor.
A self-sustaining blocking oscillator power supply circuit, comprising:
- a primary circuit formed of a DC voltage connected to a switching transistor through a primary of a transformer;
- rectifying means connected to a secondary of the transformer for producing a DC output voltage;
- regulating circuit means connecting to a control input of the switching transistor for controlling the switching transistor as a function of a comparison voltage derived from the primary circuit;
- an integration means connected parallel to the DC supply voltage for producing a periodic, approximately sawtooth-shaped signal which substantially corresponds to a current flowing in the primary circuit at the primary of the transformer, the sawtooth-shaped signal driving the regulating circuit means for triggering of the switching transistor;
- and a control means coupled to the switching transistor for converting said periodic sawtooth-shaped signal into a proportional current, an output current of said control amplifier means driving the switching transistor during its on time.
A self-sustaining blocking oscillator power supply circuit, comprising:
- a primary circuit formed of a DC supply voltage connected to a switching transistor through a primary of a transformer;
- rectifying means connected to a secondary of the transformer for producing a DC output voltage;
- regulating circuit means connecting to a control input of the switching transistor for controlling the switching transistor as a function of a comparison voltage derived from the primary circuit;
- an integration means connected parallel to the DC supply voltage for producing a periodic, approximately sawtooth-shaped signal which substantially corresponds to a current flowing in the primary circuit at the primary of the transformer, the sawtooth-shaped signal driving the regulating circuit means for triggering of the switching transistor;
- the transformer having a feedback winding for production of a feedback means signal proportional to a signal in the primary winding;
- and a limiter amplifier means driven by the feedback signal for the production of a signal with two predetermined levels which correspond in each case to zero passages of the feedback signal which go positive or negative.
Dependencies are inferred from the claim text.