Info or recomendation on STK412-140 chip

[abel2b]

Hello, good morning, I have 3 STK chips laying around ( STK4182II, STK4211II and STK412-140) and would like to build a triamp system.

My problem is the STK412-140 of which I can not find a specific data of its power handling or data sheet ( well yes the STK412-150) and therefore decide whether to use it for high,mid or sub, but looking around the web for audio equipment that use this chip, for example the Aiwa Cx-jds55 claim to have 150w + 150w outputs, others like a cheap magnavoz claims to be 70w + 70W, even I read some JVC manuals that claim to be 40W + 40W outputs, so can someone tell me what power it is capable of, or what voltage for VH+/- and VL+/- to use and build the PCB so I can use it ???

Thank you..

 

[abel2b]

can´t belive no feedback...

 

[aparatusonitus]

As no datasheet is available for STK412-140, it all comes down to speculation or at best to educated guess. So, what do we know as a fact:

1) The STK412-140 uses the largest housing in the series, so we can assume that it can withstand quite high voltages and dissipation

2) From the Sony CX-JDS55 service manual we can see that it is possible to use as high as +/-73VDC for +/-VH (no signal).

3) If we look at the datasheet for STK412-150 from the table on page 2 in the column for STK412-020, we see that the max. voltage for VL=+/-45VDC (No signal) , if VH=+/-73VDC (no signal). I would use these (conservative) values if I want to power 8 Ohm speakers.

4) From the same column for STK412-020, we can see that the recommended voltage for VL=+/-32VDC, if VH=+/-45VDC. I would use these (conservative) values if I want to power 4 Ohm speakers

5) If you feel adventurous (and you want to squeeze the maximum power out of the STK412-140 and still be on the safe side), from the same table in the columns for STK412-150 and STK412-170 we can see that the recommended values for VH=+/- 57VDC and VL=+/-38VDC for 6 Ohm load, respectively VH=+/-54VDC and VL=+/-37VDC for 4 Ohm load

Important notes from datasheet:

*4. Design circuits so that (|VH| - |VL|) is always less than 40 V when switching the power supply with the load connected.

*5. Set up the VL power supply with an offset voltage at power supply switching (VL - LO) of about 11V as an initial target.

See also STK412-150C-E datasheet as your reference.

 

[abel2b]

As no datasheet is available for STK412-140, it all comes down to speculation or at best to educated guess. So, what do we know as a fact:

Important notes from datasheet:

*4. Design circuits so that (|VH| - |VL|) is always less than 40 V when switching the power supply with the load connected.

*5. Set up the VL power supply with an offset voltage at power supply switching (VL - LO) of about 11V as an initial target.

See also STK412-150C-E datasheet as your reference.

Thank you, for your time, I apreciate the info... I was going the same route and try and use STK412-040 parameters just to give me some headroom..