Patent · US Expired

Driver circuit device

US5959472A · kind A · utility

31Cited by
4References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 28, 1997
Grant dateSep 28, 1999
Priority date
Expiry dateJan 28, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02D10/00
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

In the constant current drive type driver used for an LVDS (low voltage differential signal) interface, the parasitic capacitance of the package pins is charged and discharged sufficiently at a high speed to secure the high speed signal transmission operation. Further, the AC differential amplitude large enough to be received by the receiver can be obtained. The driver circuit device comprises: a transmit circuit composed of transistors (52, 53, 56, 57) for transmitting a signal by switching the signal current direction flowing through a pair of transmission lines (8, 9) connected between two output terminals (13 and 13B); and a constant current source composed of transistors (54, 75) for controlling the current value of the transmit circuit. In the idle state, only one of the two transistors (54 and 75) of the constant current source is turned on to limit the signal current flowing through the output terminals (13 and 13B). On the other hand, in the high speed signal transmission, both the transistors (54, 75) are turned on to increase the signal current flowing through the output terminals (13, 13B) to obtain a signal current of high DC LVDS level.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.