Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
225 words
A regulated step-down switching circuit for a DC-to-DC converter of a power supply, said DC-to-DC circuit including a pulse width modulator (PWM) with a switching transistor for receiving a first supply potential and supplying a control signal, said switching circuit comprising: a MOS-FET receiving said first supply potential at a first source/drain and supplying said first supply potential at a second source/drain in response to said control signal applied to a control gate of said MOS-FET; a first diode and a first capacitor connected in series to form a first series circuit, said first series circuit connected between said first and second source/drains of said MOS-FET for supplying a second supply potential at the common junction of said first diode and first capacitor; a second diode and a resistor connected in series to from a second series circuit, said second series circuit having a first terminal connected to said junction of said first diode and first capacitor for receiving said second supply potential and a second terminal connected to said PWM switching transistor for supplying said second supply potential thereto; and a parallel combination of a zener diode, a second capacitor and a third diode, a first node of said parallel combination receiving said first supply potential and a second node supplying said first supply potential to said PWM switching transistor through said parallel combination.
Claim 2
Dependent Claim
225 words
A regulated step-down switching circuit for a DC-to-DC converter of a power supply, said DC-to-DC circuit including a pulse width modulator (PWM) with a switching transistor for receiving a first supply potential and supplying a control signal, said switching circuit comprising: a MOS-FET receiving said first supply potential at a first source/drain and supplying said first supply potential at a second source/drain in response to said control signal applied to a control gate of said MOS-FET; a first diode and a first capacitor connected in series to form a first series circuit, said first series circuit connected between said first and second source/drains of said MOS-FET for supplying a second supply potential at the common junction of said first diode and first capacitor; a second diode and a resistor connected in series to from a second series circuit, said second series circuit having a first terminal connected to said junction of said first diode and first capacitor for receiving said second supply potential and a second terminal connected to said PWM switching transistor for supplying said second supply potential thereto; and a parallel combination of a zener diode, a second capacitor and a third diode, a first node of said parallel combination receiving said first supply potential and a second node supplying said first supply potential to said PWM switching transistor through said parallel combination.
Claim 3
Dependent Claim
32 words
The switching circuit according to claim 1, further comprising a pi network receiving said first supply potential from said MOS-FET second source/drain and supplying said first supply potential at an output terminal.
Claim 4
Dependent Claim
65 words
The switching circuit according to claim 2, wherein said pi network comprises an input node receiving said first supply potential from said MOS-FET second source/drain, a fourth diode connected from said input node to a source of ground potential, an inductor connected from said input node to an output node, and a third capacitor connected from said output node to said source of ground potential.
Claim 5
Dependent Claim
199 words
A regulated step-down circuit for use with a pulse width modulator (PWM) having a first transistor connected to an intermediate node for receiving a first potential, said regulated step-down circuit comprising: an input node for receiving a power supply second potential; a MOS-FET having a first source/drain connected to said input node for receiving said second potential, a control gate receiving a control signal from said first transistor, and a second source/drain connected to an output node for supplying an output potential; a first diode and a first capacitor connected in series forming a common node, said first diode connected in common to said input node and said MOS-FET first source/drain and said first capacitor connected to said MOS-FET second source/drain; a second diode and a resistor connected in series between said common node and said intermediate node; a parallel combination of a zener diode, third diode and second capacitor connected between said input node and said intermediate node for supplying said first potential to said first transistor; and a fourth diode having a first terminal connected in common with said MOS-FET second source/drain and said output node and a second terminal connected to a source of ground potential.
Claim 6
Dependent Claim
199 words
A regulated step-down circuit for use with a pulse width modulator (PWM) having a first transistor connected to an intermediate node for receiving a first potential, said regulated step-down circuit comprising: an input node for receiving a power supply second potential; a MOS-FET having a first source/drain connected to said input node for receiving said second potential, a control gate receiving a control signal from said first transistor, and a second source/drain connected to an output node for supplying an output potential; a first diode and a first capacitor connected in series forming a common node, said first diode connected in common to said input node and said MOS-FET first source/drain and said first capacitor connected to said MOS-FET second source/drain; a second diode and a resistor connected in series between said common node and said intermediate node; a parallel combination of a zener diode, third diode and second capacitor connected between said input node and said intermediate node for supplying said first potential to said first transistor; and a fourth diode having a first terminal connected in common with said MOS-FET second source/drain and said output node and a second terminal connected to a source of ground potential.
Claim 7
Dependent Claim
48 words
The circuit of claim 4, further comprising: an inductor connected between (i) the common connection of said MOS-FET second source/drain and said first terminal of said fourth diode and (ii) said output node; and a third capacitor connected between said output node and said source of ground potential.