STK 412-170 amps can they be bridged and run from just upper voltage line?

[rafaro]

Have several STK 412-170 and plan to use them as amp modules inside linear array speaker sytems. Need to know if they can be bridged and can they be operated just from the Vh high voltage inputs without connecting the lower voltage lines with pins 2-5 not connected

[pacificblue]

You have two options to work with one rail voltage only. If the voltage is below 60 V idle and 37 V loaded, connect pins 2 and 5 and forget about pins 1, 3, 4 and 6.
If the voltage is above either of those values, connect V+ to pins 1 and 3, V- to 4 and 6, so that the comparator always switches the power stage to the high voltage pins. Leave pins 2 and 5 open.
You must be aware that this approach leads to much higher power dissipation than the chip was designed for and heatsinking will become the limiting factor.

The same goes for bridging. Yes, they can be bridged, but you must expect even higher heat dissipation.

[rafaro]

have the dual voltage transformer but seems that a dual voltage design would be too complicated?? Where can I get the design schematic/PCB for this part of the design? I am willing to try it as a class G amp with assistance
I do need about 8 of these units!!

[rafaro]

Want to have that option I will increase heat sinks as needed. Thanks for the help!!

[pacificblue]

Originally Posted by rafaro

have the dual voltage transformer but seems that a dual voltage design would be too complicated?? Where can I get the design schematic/PCB for this part of the design?

The complicated part is already inside the STK. It takes two power supplies, instead of one, two Zener diodes with resistors as voltage raference for the internal comparator, and another pair of resistors and caps to stabilize the supply for input and bias stages.

You have PM.