diyAudio (
-   Construction Tips (
-   -   digital amp power switching questions (

suaveman 21st January 2013 06:40 AM

digital amp power switching questions
So i have a ddx320 i bought, powered by a agt 350w 36v supply running at 35v. Works great powering two 8 ohm acoustic research 215ps (freebies, was suprized to find out they are actually decent speakers), 100w rms, and a 3 ohm sony ss-wsb102 @ 130w rms. Configured as a 2.1 setup.

Now that i have the proto-build up and running, i'm planning on doing a decent job at putting it in an old vcr chassis with all the components removed/new front/back panels.

What i want to do, is put a simple rf remote reciever, on/off switching ac at up to about 25w loads iirc in the chassis with the smps, dac amp, and a adc converter/power supply for a analog input.

Obviously, that isn't going to work without some relays/mosfets (and fuses obviously). The plan is to have 2 25a ac rated ssr relays switch the smps on, both the ac line and hot wires, ie spst dual ssr's wired off the same 5v 1a ac/dc adapter, thats turned on by the rf ac switch, opening and closing neg/hot ac wires to the smps.

Then have a time delay circuit of a few seconds or so, i know of some circuits i've come across that can do this, to switch 2 d209l npn's for the 35v 9.6a peak load coming out of the smps. IE, let the smps power up, then after a delay switch the +/- dc from the smps to the digital amp, as well as the adc ac/dc supply using a relay (5v 1a supply for the adc) from the same time delay trigger circuit for the mosfets, possibly requiring some kind of voltage regulation if the two don't match up (d209l's, and the relay, or possibly a small mosfet at the same gate voltage instead). Powered by a ac/dc adapter of sufficient voltage for the mosfets to turn on fully.

Is this overkill?

do i just need to switch the ssr's to power a small ac block for the transformers (smps, adc power supply)? Also, do i need to be switching both the hot/- ac lines?

I know most switch applications don't do this, but i want total power isolation, and if necessary a time delay/additional dual -/+ mosfet switch circuit for the dc out to the ddx320.

Is it ok to mount all this in one chassis? or should i do the d-amp seperately from the ac/dc smps's and relays/mosfet switches/adc & adc ac/dc supply switching/rf ac low wattage trigger switch?

Would mounting everything in one enclosure, with just a dplug 3 pin input to the ssr's/power supply's for the time delay'ed mosfet switches, and rf ac switch to power a ac/dc adapter to trigger said ssr's/mosfet switch curcuits introduce distortion/noise into the system?

Obviously, i'm going to put the d-amp in a plastic project box, with a 12v fan (another thing i need to switch on, 12v ac/dc supply for the fan, or a lower voltage supply if theres not much heat)| to isolate the digital/analog grounds from the ac ground in the chassis, but would it be best to have a power switching chassis/module, and have my d-amp away from all that circuitry? Or am i just being paranoid about interference/noise from the ac being so close to the amp board?

Any advice, or suggestions as to how to switch on the smps, fans, adc converter power supply, and if time delay's and neg/pos switching is a good idea or just overkill is much apprecciated. As well as if i'm using the right transistor, or suggestions for alternatives/simpler solutions.


All times are GMT. The time now is 01:01 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 18.75%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio