| 摘要 |
<p>A slew-rate controlled switching circuit comprises a transistor having a source coupled to a power supply; a pull-up resistor having a first terminal coupled to the source of the transistor; a gate resistor having a first terminal coupled to the gate of the transistor and a second terminal coupled to a second terminal of the pull-up resistor; and a feedback capacitor having a first terminal coupled to the gate resistor and a second terminal coupled to the drain of the transistor. The second terminal of the gate resistor forms a circuit input. The feedback capacitor is enhanced by the Miller effect. The gate resistor limits the rate at which charge states of the capacitances present at the gate of the transistor can change. When the circuit input is switched from a high value to a low value, the drain voltage increases smoothly and nearly linearly from a low value to a high value at a rate proportional to the product of the value of the gate resistor and the value of a capacitance present between the gate and the drain. The time required for the drain voltage to switch from its low value to its high value is sufficient to enable a power supply to respond to changing current demand.</p> |
