Hello guys,
i have brought me a nice little preamp, the yamaha w-xc 50 which is currently feeding my old Yamaha M-45. i want to replace the power amp with something less room-heating but still nice sounding.
For this task i have ordered an icepower 125asx2.
The wxc has a low impedance ( 2V 470Ohm output), therefore i dont need a buffer stage.
I am wondering about the enable pin of the icepower module. It´s active high (5V) and must be short to ground to deactivate the amp.
Do you think a simple active open relais to GND will be enough to control the Icepower with the help of the 12V Trigger signal? (WCX off = 0V = Relais short to ground = Icepower switched off)
Sorry for my bad english and the spelling.
Greetings from germany Kai
i have brought me a nice little preamp, the yamaha w-xc 50 which is currently feeding my old Yamaha M-45. i want to replace the power amp with something less room-heating but still nice sounding.
For this task i have ordered an icepower 125asx2.
The wxc has a low impedance ( 2V 470Ohm output), therefore i dont need a buffer stage.
I am wondering about the enable pin of the icepower module. It´s active high (5V) and must be short to ground to deactivate the amp.
Do you think a simple active open relais to GND will be enough to control the Icepower with the help of the 12V Trigger signal? (WCX off = 0V = Relais short to ground = Icepower switched off)
Sorry for my bad english and the spelling.
Greetings from germany Kai
The relay would work well, but you can get the same result with a transistor and a couple of resistors or - if you want to be sure that you don't get any grounding issues or similar - an optocoupler with a resistor to control the LED current.
For a transistor based inverted switch i think i need the auxillary supply and a NAND Logic. Or am i overthinking the circuit?
I mean i want the "switch" to be open when 12V is supplied by the preamp and closed when the 12V is truned of, to short the 5V to GND. Therefore i would have to put a logic NAND between 12V and the Optocoupler and i need an additional supply for the second NAND Input.
With the realis i only need the additional diode and i`m done.
Please correct me when i am wrong.
I mean i want the "switch" to be open when 12V is supplied by the preamp and closed when the 12V is truned of, to short the 5V to GND. Therefore i would have to put a logic NAND between 12V and the Optocoupler and i need an additional supply for the second NAND Input.
With the realis i only need the additional diode and i`m done.
Please correct me when i am wrong.
Hi Blaukomma,
You will find a complete schematics of a 125 ASX2 amp including input buffer and enable section.
on the post below :
https://www.diyaudio.com/forums/class-d/341250-500w-icepower-usd-100-deal-17.html#post5914545
On 125ASX2 manual :
Enable pin
The enable pin can enable/disable the amplifier. If the pin is left unconnected, then the level is high (+5V) and the ampli-fier is enabled. If the pin is pulled low (0V) externally, the amplifier will be disabled.
The enable pin will also be pulled low by the internal pro-tection circuitry if the amplifier temperature becomes too high or a mains under- voltage is detected. This pin is bidi-rectional.
BR,
Pascal
You will find a complete schematics of a 125 ASX2 amp including input buffer and enable section.
on the post below :
https://www.diyaudio.com/forums/class-d/341250-500w-icepower-usd-100-deal-17.html#post5914545
On 125ASX2 manual :
Enable pin
The enable pin can enable/disable the amplifier. If the pin is left unconnected, then the level is high (+5V) and the ampli-fier is enabled. If the pin is pulled low (0V) externally, the amplifier will be disabled.
The enable pin will also be pulled low by the internal pro-tection circuitry if the amplifier temperature becomes too high or a mains under- voltage is detected. This pin is bidi-rectional.
BR,
Pascal
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