Quad Power Supply For Hybrid Amplifier

Posted on Feb 5, 2014

This power supply was designed for use with the Simple hybrid amp` published elsewhere in this issue. It is of course suitable for use in other applications as well. We`ve used a cascade generator for the 170 V, a switch mode supply for the 16 V, a series regulator for the 12 V and a separate transformer for the 6. 3 V filament supply. We`ve chosen

Quad Power Supply For Hybrid Amplifier
Click here to download the full size of the above Circuit.

an LT1074CT (IC1) for the regulator, which means that the circuit can be built with relatively standard components and will have a high efficiency. The power loss is less with this device compared to a linear voltage regulator. This allows us to use a higher transformer voltage and a smaller cascade section to generate the 170 V (which is required for the SRPP stage in the amplifier). The lower input current also results in smaller losses in the bridge rectifier (D1 to D4). A standard 12 V regulator (IC2) turns the 16 V into a stabilised voltage for the buffer stage. When an ECC83 (12AX7) is used in the hybrid amp we could use this 12 V to power the filaments in the valve as well, although we really need 12. 6 V. The current taken by the valve is about 150 mA, which means that the 12 V regulator needs to be fitted with a heatsink. This can be a small version of an SK129 heatsink from Fischer (38. 1 mm, 6. 5 K/W). To increase the voltage by 0. 6 V we`ve added diode D7 to the ground connection of the regulator. If an output voltage of 12 V is required you should close JP1, which shorts D7. IC1 and D5 require a little more cooling and for this the 63. 5 mm version of the SK129 will suffice (4. 5 K/W). Both components can be mounted on opposite sides of the heatsink. You have to make sure that they are electrically isolated from each other and the heatsink! You should take a look at the website of Linear Technology ( and take...

Leave Comment

characters left:

New Circuits



Popular Circuits

Power Supply with Adjustable Current and Voltage
Fuzz box 5
controller 4017 counter LEDs have multiple connections in this traffic light circuit
learning How does this SIM card reader circuit work
Flame Sensor
simple supply voltage monitor
receiver circuits
simple 12db/octave filter
Alternating current voltage amplifier transistor