| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a power supply, along with a lighting device and power measurement system, capable of simplifying a circuit for input power measurement. <P>SOLUTION: The step-up chopper power supply includes: an integrator 2 that outputs detection voltage Vcd in proportional to voltage obtained by integrating voltage obtained by half-wave-rectifying both end voltages across an inductor L1 by an amount equivalent to at least one period of turn-on/off of a switching element Q1; and a computation unit 3 that computes input power based on the detection voltage Vcd output by the integrator 2. The detection voltage Vcd output by the integrator 2 is proportional to the product of input voltage Vin from a power supply and the duration of the on-state of the switching element Q1. Accordingly, the circuit can be simplified as compared with cases where the duration of the on-state of the switching element Q1 is counted. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
