AVCC 2.1 - module update

[Russ White]

Originally Posted by Erlend Sæterdal

Thank you.

[Lazybutt]

Hi Russ,
I'm sure the question has already been asked, but why does the AVCC need to share the voltage reference..? in other words, why can't Tridents be used in place of the AVCC module ?

[Lazybutt]

Originally Posted by glt

I've seen photos where the leds have different brightness (including mine). Although that is not an issue, is the new design better at having equal brightness?

That's quite strange..... from what I understand of the circuit design (if the LEDs are the same of course) , you should not be able to see the difference. The current through both should be close enough that you should not be able to distinguish a brightness difference....
It happened to me and I found it was when the Shunt Power supply to the Buffalo board was under powered (too low CCS setting..).. you should check that you are shunting enough current in your Placid if that's what you use...

[Russ White]

Originally Posted by Lazybutt

Hi Russ,
I'm sure the question has already been asked, but why does the AVCC need to share the voltage reference..? in other words, why can't Tridents be used in place of the AVCC module ?

You can absolutely use two trident's but the left and right output will then not be as exactly matched, and any variation will not be present on both sides at the same time. This can have an adverse effect on stereo imaging.

[glt]

Originally Posted by Lazybutt

That's quite strange..... from what I understand of the circuit design (if the LEDs are the same of course) , you should not be able to see the difference. The current through both should be close enough that you should not be able to distinguish a brightness difference....
It happened to me and I found it was when the Shunt Power supply to the Buffalo board was under powered (too low CCS setting..).. you should check that you are shunting enough current in your Placid if that's what you use...

Thanks for the tip. Will check.

[hochopeper]

Originally Posted by glt

I've seen photos where the leds have different brightness (including mine). Although that is not an issue, is the new design better at having equal brightness?

I always thought that was caused by different exposure times/ambient lighting. I don't think photos are a great way to judge LED brightness ...

OR are you talking about the 2 leds on the same module? IE 2 leds in the same photo?

[Russ White]

Actually there could be ~1ma difference in current through the LEDs. The reason is the base current of the transistors that reference the LED. Still if the voltage is in the right range they should be very similar.

[Jeffrey Davison]

ETA on the new AVCC modules?

Thanks

JD

[BrianDonegan]

A few weeks. They are being built now...

[Jeffrey Davison]

Is it soup yet?

JD