Current-sensing circuit and air-conditioning device provided therewith
US8861232B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 18, 2010 |
| Grant date | Oct 14, 2014 |
| Priority date | — |
| Expiry date | Apr 2, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R19/0092
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The current-sensing circuit (1) includes a shunt resistor (R1) connected in series with a path of current from an inverter (106), an operational amplifier (12) amplifying voltage across both ends of this shunt resistor (R1) with a predetermined gain, a low-pass filter (18) averaging output voltage of this operational amplifier (12), and an arithmetic unit (50) calculating the current flowing through the path based on output voltage of the low-pass filter (18). The supply voltage of the operational amplifier (12) is set higher than the supply voltage of the arithmetic unit (50). The output voltage of the operational amplifier (12) is averaged at the low-pass filter (18) to a lower value than the supply voltage of the arithmetic unit (50).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.