Digital-to-analog converter circuit and method
US7724172B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 2008 |
| Grant date | May 25, 2010 |
| Priority date | — |
| Expiry date | Mar 5, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01K7/015
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A digital-to-analog converter, in response to a digital signal, selectively taps a resistor string to generate an analog output and selectively shunts around resistors in the string to voltage shift the analog output. If two supply voltage sets are present, two strings are provided. A mutually exclusively selection of outputs is made to select a source of the analog output. An integrated circuit temperature sensor uses the converter and includes a sensing circuit that determines exposure to one of a relatively low or high temperature. A measured voltage across the base-emitter of a bipolar transistor is selected in low temperature exposure and compared against a first reference for a too cold temperature condition. Alternatively, a measured delta voltage across the base-emitter is selected in high temperature exposure and compared against a second reference voltage for a too hot temperature condition. Through the comparisons, a temperature exposure detection is made.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.