Low power method and interface for generating analog waveforms
US7057543B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 2004 |
| Grant date | Jun 6, 2006 |
| Priority date | — |
| Expiry date | Apr 29, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/10
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A low power analog output circuit is disclosed that utilizes a low pass filter driven by a bit stream to render a waveshaped output signal based upon a raw digital data signal. The analog output circuit includes sequential bit pattern selection logic that receives as an input, the raw digital data signal. The analog output circuit also includes a bit pattern storage that specifies bit stream sequences that are selected in accordance with control signals generated by the state machine based upon its current state and the current raw digital data signal. The analog output circuit includes an output stage driven by a digital input signal corresponding to values provided by a bit stream sequence selected from the bit pattern storage. The output stage comprises a low pass filter circuit having an effective time constant that is greater than a hold period associated with a single bit of the bit stream sequence that drives the digital input signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.