Turn on/off thump with "others" D amps...how it is managed?

pat allen · 15th March 2005, 04:33 PM

Hi, i am wondering how the turn on/off thump is managed on other modules like UCD or ICE modules. Do they have thump might be the initial question.
If not, how the design permit a direct connection from the LC filter to the speaker?

As an example, my IR redisign uses a mute relay because upon turn on, there is a dead time forced to charge the bootstrap cap. I know UCD or ICE module differ a lot, i am just wondering because it looks like there is no relay at all.

thanks.

Jan-Peter · 15th March 2005, 05:04 PM

Pat,

Indeed in the UcD modules we do not have any relay. We switch ON/OFF the currentsource of the two PNP differential input transistors. Please check the schematic from the UcD what is yet public known.

Regards,

Jan-Peter

Pierre · 15th March 2005, 05:08 PM

Is there a link for that schematics? Or you refer only to the UcD patent?

Thanks!

Jan-Peter · 15th March 2005, 05:11 PM

Pierre,

Please check this http://www.diyaudio.com/forums/attac...amp=1110300548

Jan-Peter

pat allen · 15th March 2005, 05:15 PM

Ok, so there is absolute no turn on/off thump?

How is the current source turned on/off, with a constant simple delay, microprocessor controled, manualy??
Is it totaly self contained?

Is there some active protection on these UCD modules?

thanks.

Jan-Peter · 15th March 2005, 05:23 PM

Indeed there is only silence when you switch the UcD amp on.....

(however to be honest, when you put your ear in front of the loudspeaker you will hear a very small "thick")

We wait for one second so that the bootstrap capacitor can be fully charged, and the we switch the current source on.

We use this ON/OFF part to switch OFF the UcD when there is an overvoltage. In the first version of the UcD180/400 we used a piek current protection hereby was also this mute section used.

However we use now a constant current limiter in the UcD modules, this works in a different way and is confidential.......

Regards,

Jan-Peter

pat allen · 15th March 2005, 05:31 PM

Thanks.
Sorry to ask, how can the bootstrap cap be charged if Vout=0?
In my understanding, it have to be -vcc as long as it needs to be charged?

Jan-Peter · 15th March 2005, 05:37 PM

Sorry, confidential.......

But it works

Jan-Peter

pat allen · 15th March 2005, 05:41 PM

Ok, i think i get it anyway....while i was playing with the PB12 module, i was "forcing" the bootstrap cap to be charged...it is grounded by the speaker resistance then, so...

thanks very much.

ghemink · 16th March 2005, 02:24 AM

Quote:

Originally posted by pat allen
Ok, so there is absolute no turn on/off thump?

How is the current source turned on/off, with a constant simple delay, microprocessor controled, manualy??
Is it totaly self contained?

Is there some active protection on these UCD modules?

thanks.

As Jan-Peter said, only a very small thump when you put your ear close to the speakers. I have these modules directly connected to my tweeter, midranges and woofers (active system). Very well on/off switching behavior. No relay needed in between amps and speakers.

Gertjan

15th March 2005, 04:33 PM	#1
pat allen diyAudio Member Join Date: Dec 2004 Location: Quebec	Turn on/off thump with "others" D amps...how it is managed? Hi, i am wondering how the turn on/off thump is managed on other modules like UCD or ICE modules. Do they have thump might be the initial question. If not, how the design permit a direct connection from the LC filter to the speaker? As an example, my IR redisign uses a mute relay because upon turn on, there is a dead time forced to charge the bootstrap cap. I know UCD or ICE module differ a lot, i am just wondering because it looks like there is no relay at all. thanks. __________________ Electronic engineer for automotive market.

15th March 2005, 05:15 PM	#5
pat allen diyAudio Member Join Date: Dec 2004 Location: Quebec	Ok, so there is absolute no turn on/off thump? How is the current source turned on/off, with a constant simple delay, microprocessor controled, manualy?? Is it totaly self contained? Is there some active protection on these UCD modules? thanks. __________________ Electronic engineer for automotive market.

15th March 2005, 05:31 PM	#7
pat allen diyAudio Member Join Date: Dec 2004 Location: Quebec	Thanks. Sorry to ask, how can the bootstrap cap be charged if Vout=0? In my understanding, it have to be -vcc as long as it needs to be charged? __________________ Electronic engineer for automotive market.

15th March 2005, 05:41 PM	#9
pat allen diyAudio Member Join Date: Dec 2004 Location: Quebec	Ok, i think i get it anyway....while i was playing with the PB12 module, i was "forcing" the bootstrap cap to be charged...it is grounded by the speaker resistance then, so... thanks very much. __________________ Electronic engineer for automotive market.

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15th March 2005, 05:04 PM	#2
Jan-Peter diyAudio Member Join Date: Sep 2003 Location: -	Pat, Indeed in the UcD modules we do not have any relay. We switch ON/OFF the currentsource of the two PNP differential input transistors. Please check the schematic from the UcD what is yet public known. Regards, Jan-Peter

15th March 2005, 05:08 PM	#3
Pierre Banned Join Date: Nov 2004 Location: Paris	Is there a link for that schematics? Or you refer only to the UcD patent? Thanks!

15th March 2005, 05:11 PM	#4
Jan-Peter diyAudio Member Join Date: Sep 2003 Location: -	Pierre, Please check this http://www.diyaudio.com/forums/attac...amp=1110300548 Jan-Peter

15th March 2005, 05:23 PM	#6
Jan-Peter diyAudio Member Join Date: Sep 2003 Location: -	Indeed there is only silence when you switch the UcD amp on..... (however to be honest, when you put your ear in front of the loudspeaker you will hear a very small "thick") We wait for one second so that the bootstrap capacitor can be fully charged, and the we switch the current source on. We use this ON/OFF part to switch OFF the UcD when there is an overvoltage. In the first version of the UcD180/400 we used a piek current protection hereby was also this mute section used. However we use now a constant current limiter in the UcD modules, this works in a different way and is confidential....... Regards, Jan-Peter

15th March 2005, 05:37 PM	#8
Jan-Peter diyAudio Member Join Date: Sep 2003 Location: -	Sorry, confidential....... But it works Jan-Peter

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