Multi-channel, controlled amplification factor electronic amplifier construction, particularly for color TV contrast adjustment
AssigneeBlaupunkt-Werke GmbH
InventorGerald Gronau
Life of this patent
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Abstract
The multi-channel amplifier is placed on a common substrate to form a hybrid circuit network, for example a common silicon chip. A source of control voltage is provided connected in common to the base terminals of a pair of transistors, which have their emitters coupled together. The output is taken from the collector of one of the transistors via an emitter-follower transistor. The commonly connected emitters of the pair of transistors are connected through a current supply source forming a third transistor to a source of operating voltage.
Claims19
A multi-channel, controlled-amplification-factor electronic amplifier construction, for adjusting contrast in a color television monitor having contrast setting means,
- wherein each channel comprises
- first and second transistors (21, 22;
- 31, 32;
- 41, 42) forming, together, a pair, said first and second transistors being emitter-coupled, and a third transistor (22, 33, 43),
- the collector of the respective third transistor being coupled to the emitters of the first and second transistors forming the pair,
- the emitter of the third transistor being coupled, through an emitter-resistor (25, 35, 45), to a reference terminal (5) of a current supply source;
- and wherein, in accordance with the invention,
- channel input terminals (3, 8, 13) are provided, each connected to a respective base terminal of a respective one of said third transistors (22, 33, 43);
- said first one (21, 31, 41) of the transistors of each pair (21, 22;
- 31, 32;
- 41, 42) is coupled through a collector-resistor (26, 36, 46) to a second terminal (17) of said current supply source;
- and
- a respective emitter-follower transistor (24, 34, 44) is connected to the collector of said first transistor (21, 31, 41) and to a respective output terminal (2, 7, 12) of a respective channel;
- the transistors forming the pair of transistors and the third transistor (22, 33, 43) for each channel are formed on respective common substrates to provide a plurality of common substrates for each channel;
- said common substrates are all derived from the same wafer or chip;
- and
- wherein said amplifier comprises a hybrid circuit network including said common substrates for the respective channels and at least said emitter-resistors (25, 35, 45).
Multi-channel controlled amplification factor electronic amplifier construction, for adjusting contrast in a color television monitor having contrast setting means,
- wherein each channel comprises
- first and second transistors (21, 22;
- 31, 32;
- 41, 42) forming, together, a pair, said first and second transistors being emitter-coupled, and a third transistor (22, 33, 43),
- the collector of the respective third transistor being coupled to the emitters of the first and second transistors forming the pair,
- the emitter of the third transistor being coupled, through an emitter-resistor (25, 35, 45), to a reference terminal (5) of a current supply source;
- and wherein, in accordance with the invention,
- the transistors forming the pair of transistors and the third transistor (22, 33, 43) for each channel are formed on respective common substrates to provide a plurality of common substrates for each channel;
- said common substrates are all derived from the same wafer or chip;
- said amplifier comprises a hybrid circuit network including said common substrates for the respective channels and at least said emitter-resistors (25, 35, 45);
- auxiliary inputs (1, 6, 11) are provided, each coupled to the collector of a respective one of said first transistor of each pair;
- and
- clamping circuits (68-76) are provided, each connected to a respective one of said auxiliary inputs (1, 6, 11).
Dependencies are inferred from the claim text.