Low side line driver
US5717557A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 1994 |
| Grant date | Feb 10, 1998 |
| Priority date | — |
| Expiry date | Sep 12, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/0016
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A low side line driver (10) includes a slew rate limiter (12) providing current to a pre-charge reference circuit (16). The pre-charge reference circuit (16) generates a constant voltage at the input of a pre-drive circuit (18). Upon a transition to the active state, the pre-charge reference circuit (16) is disabled and current from the slew rate limiter (12) flows to pre-drive circuit (18) which becomes enabled without undue propagation delay or high instantaneous slew rate due to the pre-charge voltage generated by the pre-charge reference circuit (16) before turn on. The pre-drive circuit (18) provides base current to an output driver (22) from a negative voltage created in a charge pump (28). At turn off, an active turn off circuit (26) produces a short output pulse causing rapid discharge of base capacitance of the output driver (22) in order to minimize turn off propagation delay.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.