The datasheet lacks a graph, a power output vs supply voltage at 4 ohms graph.
So what is the recommended DC voltage for the 1875 with a 4ohm load? Have a 2.7 C/watt sink, no insulation/mica used. In cold, cold UK.
So what is the recommended DC voltage for the 1875 with a 4ohm load? Have a 2.7 C/watt sink, no insulation/mica used. In cold, cold UK.
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datasheet lm1875t...........national:
The LM1875 delivers 20 watts into a 4Ω or 8Ω load on ±25V
supplies. Using an 8Ω load and ±30V supplies, over 30
watts of power may be delivered.
i think this means not to exceed +- 25V with a 4 ohm load (and a proper heatsink).......
(speaker load 4 ohm minimum or bigger)
The LM1875 delivers 20 watts into a 4Ω or 8Ω load on ±25V
supplies. Using an 8Ω load and ±30V supplies, over 30
watts of power may be delivered.
i think this means not to exceed +- 25V with a 4 ohm load (and a proper heatsink).......
(speaker load 4 ohm minimum or bigger)
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IMO, these 5 pin 220 cased chip amps should be limited to +/- 18 volts on 4 Ohm loads. You're really pushing things when you go higher. Loads can be reactive and difficult to drive. The TDA2050 has 5 amp peak current for more wiggle room, but I'd still stay under +/- 20v.
If you need more power, move on to a stronger chip.
If you need more power, move on to a stronger chip.
How about this for 4 ohm load?
http://www.diyaudio.com/forums/chip-amps/112048-can-set-up-increase-output-power-lm1875-4-ohms.html
The booster transistors spread the thermal load so the little To220 package is not dissipating all the power
http://www.diyaudio.com/forums/chip-amps/112048-can-set-up-increase-output-power-lm1875-4-ohms.html
The booster transistors spread the thermal load so the little To220 package is not dissipating all the power
yeah, hooked it up to +/-16V and the chip is pretty warm, though the sink is doing its job
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