Band-gap reference circuit with chopping circuit
US10114400B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 2016 |
| Grant date | Oct 30, 2018 |
| Priority date | — |
| Expiry date | Jan 26, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/6872
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A BGR circuit for sub-1V ICs utilizes a voltage chopping circuit and/or a current chopping circuit and a low-frequency filter to stabilize the output reference voltage that is generated by an op-amp, a current mirror circuit, a CTAT stage, a PTAT stage, and an output stage. The voltage chopping circuit reduces input offset and 1/f noise by periodically alternating (time-averaging) the negative temperature dependent and positive temperature dependent voltages supplied by the CTAT and PTAT stages to the op-amp's input terminals. The current chopping circuit minimizes current variations caused by process-related differences in the current mirror devices by periodically alternating (time-averaging) three balanced currents generated by the current mirror circuit such that each current is transmitted equally to each of the CTAT, PTAT and output stages. The filter serves to maintain loop stability and remove the low frequency noise generated by the applied voltage and/or current chopping operations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.