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AssigneeLinear Technology Corporation
InventorsCarl T. Nelson, Robert Essaff
Estimating the term…
Circuits and methods are provided for increasing the turn-off switching speed of a high-speed integrated circuit, bipolar switching regulator. The regulator The circuit runs at megahertz frequencies, yet is efficient as previously available bipolar integrated circuit switching regulators operating at much lower frequencies. The increased speed switch turn-off circuitry prevents the switch from spending too much time in a high power state (which would slow the switch down), increases the stability of the switch as compared with previously known designs. In a preferred embodiment, the circuitry includes a PNP transistor and a diode-connected transistor with their base-emitter circuits coupled to form a loop with the base-emitter circuit of a NPN transistor and the base-collector circuit of the switch to limit the on state voltage of the switch and control its depth of saturation. A capacitor is connected across the diode-connected transistor to reduce instabilities due to ringing caused by delays in the feedback loop.
A circuit for controlling the speed at which a switch transistor turns off by limiting the depth of saturation of the switch transistor, the switch transistor having a base, an emitter, a collector, and a collector-emitter voltage, the circuit comprising:
A circuit for controlling the speed at which a switch transistor turns off by limiting the depth of saturation of the switch transistor, the switch transistor having a base, an emitter, a collector, and a collector-emitter voltage, the circuit comprising:
A method for reducing ringing in a circuit which limits the depth of saturation of a switch transistor in a regulator circuit, the switching transistor having a base an emitter, a collector, and a collector-emitter voltage, the method comprising the steps of:
Dependencies are inferred from the claim text.