Communication line driver, LSI for interface including such a circuit and communication terminal apparatus
US5539771A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jan 6, 1994 |
| Grant date | Jul 23, 1996 |
| Priority date | — |
| Expiry date | Jan 6, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/0272
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A communication line driver for a communication interface includes on one chip, a trimming circuit for adjusting a reference voltage generated by a reference voltage generating circuit, a driving device for transmitting a signal to a communication line; a buffer for applying a constant voltage to the driving device by a constant voltage control based on an output of the trimming circuit, and a bias circuit for deciding an internal operating current of the buffer on the basis of the output of the trimming circuit. The buffer further includes an MOS transistor which operates as a current limiter and functions to limit the current in case of an overload. Thus, a resistor for the current control is unnecessary. An electric power consumption can be reduced by the current limitation at the time of overload.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.