Saturating Video Driver
Original Publication Date: 1982-Jul-01
Included in the Prior Art Database: 2005-Feb-09
The video driver in a CRT display is required to switch its output voltage between two well-defined levels, about 50 volts apart. A saturating driver has the inherent advantage that its output can be made to switch between levels which are within a fraction of a volt of the supply voltage rails. This leads to minimum dissipation and allows the use of relatively low breakdown voltage transistors. Unfortunately, a saturating driver suffers from the storage delay phenomenon in the on transistors, and this has prevented its use in high performance displays. However, by careful design of the timing and impedance of the base-driver waveforms, a saturating driver can be made, which switches at least as fast as existing non-saturating circuits, while retaining the advantages of saturation.