Analog to digital converter using complementary differential emitter pairs
US5550492A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 1, 1994 |
| Grant date | Aug 27, 1996 |
| Priority date | — |
| Expiry date | Dec 1, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45612
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A differential amplifier operating as a magnitude amplifier may be used in a serial-type A/D converter. The differential amplifier uses complementary differential emitter pairs for folding and aligning a differential input signal. The differential input signal has a first signal and a second signal each of which is fed to one of two input circuits. One input circuit includes a bipolar npn transistor and a current sink and the other includes a bipolar pnp transistor and a current source. The outputs of the input npn transistors feed a differential pair of output pnp transistors. The emitters of the output pnp transistors are coupled, with the signal on the emitters following the lower of the differential input signals. The outputs of the input pnp transistors feed a differential pair of output npn transistors. The emitters of the output npn transistors also are coupled, with the signal on the emitters following the inputs in a predetermined manner. The results are folded signals at the outputs of the output transistors that are aligned by offset circuits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.