EP 1125360 A2 20010822 - A VIDEO OUTPUT AMPLIFIER
Title (en)
A VIDEO OUTPUT AMPLIFIER
Title (de)
VIDEOAUSGANGSVERSTÄRKER
Title (fr)
AMPLIFICATEUR DE SORTIE VIDEO
Publication
Application
Priority
- DK 9900579 W 19991022
- DK PA199801371 A 19981023
Abstract (en)
[origin: WO0025420A2] Output amplifiers for driving picture tubes need to provide a high slew rate, and traditional class-A amplifiers have a high quiescent power consumption because of the high supply voltage combined with the necessary high quiescent current. According to the invention, the quiescent current is constituted mainly of the DC feedback current in the output device (TR3), and its control electrode is driven by means of a transistor (TR1), whose base has a reference potential, and whose emitter receives the static component of the control signal for the picture tube. In one embodiment the quiescent power consumption is 10-15 % of that of a corresponding class-A amplifier, and the required cooling means may be considerably reduced.
[origin: WO0025420A2] Output amplifiers for driving picture tubes need to provide a high slew rate, and traditional class-A amplifiers have a high quiescent power consumption because of the high supply voltage combined with the necessary high quiescent current. According to the invention, the quiescent current is constituted mainly of the DC feedback current in the output device (TR3), and its control electrode is driven by means of a transistor (TR1), whose base has a reference potential, and whose emitter receives the static component of the control signal for the picture tube. In one embodiment the quiescent power consumption is 10-15 % of that of a corresponding class-A amplifier, and the required cooling means may be considerably reduced.
IPC 1-7
IPC 8 full level
H03F 3/19 (2006.01); H03F 3/30 (2006.01); H04N 5/14 (2006.01); H04N 9/64 (2006.01)
CPC (source: EP)
H03F 3/19 (2013.01); H03F 3/3067 (2013.01); H04N 5/148 (2013.01); H04N 9/648 (2013.01)
Citation (search report)
See references of WO 0025420A2
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL
DOCDB simple family (publication)
WO 0025420 A2 20000504; WO 0025420 A3 20000727; AU 6326399 A 20000515; EP 1125360 A2 20010822
DOCDB simple family (application)
DK 9900579 W 19991022; AU 6326399 A 19991022; EP 99950509 A 19991022