| 摘要 |
<p>A current-sensing and correction circuit having programmable temperature compensation circuitry that is incorporated into a pulse width modulation controller of a buck mode DC-DC converter. The front end of the controller contains a sense amplifier, having an input coupled via a current feedback resistor to a common output node of the converter. The impedance of a MOSFET, the current through which is sampled by a sample and hold circuit is controlled by the sense amplifier unit. A sensed current correction circuit is coupled between the sample and hold circuit and the controller, and is operative to supply to the controller a correction current having a deterministic temperature-compensating relationship to the sensed current. The ratio of correction current to sensed current equals a value of one at a predetermined temperature, and has other values at temperatures other than at that temperature.</p> |
