Title :
A delta-sigma true RMS-to-DC converter using an indirect-charge-transfer filter
Author :
Wei-Shinn Wey ; Yu-Chung Huang
Author_Institution :
Inst. of Electron., Nat. Chiao Tung Univ., Hsinchu, Taiwan
Abstract :
An indirect charge transfer (IDCT) technique is applied to a delta-sigma (/spl Delta//spl Sigma/) true RMS-to-DC converter. This technique makes the converter gain depend only on the capacitors´ ratio. It reduces the gain drift and the absolute gain error. The RMS-to-DC converter is fabricated in a 0.8 /spl mu/m double-poly double-metal (DPDM) CMOS process. Measured results show that, with no trimming and calibration required, this converter achieves an absolute error /spl plusmn/0.8% of reading, even with input RMS levels up to 800 mV.
Keywords :
CMOS integrated circuits; delta-sigma modulation; digital instrumentation; switched capacitor filters; 0.8 micron; 800 mV; absolute gain error; delta-sigma converter; double-poly double-metal CMOS process; gain drift; indirect-charge-transfer filter; multiplying DAC; true RMS-to-DC converter; CMOS process; Calibration; Capacitance; Capacitors; Charge transfer; Circuits; Filters; Frequency conversion; Operational amplifiers; Very large scale integration;
Conference_Titel :
VLSI Circuits, 1999. Digest of Technical Papers. 1999 Symposium on
Conference_Location :
Kyoto, Japan
Print_ISBN :
4-930813-95-6
DOI :
10.1109/VLSIC.1999.797247
