Rank: Administration
Groups: Administration, Customer Joined: 10/24/2006(UTC) Posts: 3,979 Location: Nashville, TN
Thanks: 25 times Was thanked: 89 time(s) in 83 post(s)
|
Do you have VA connected to a supply?
|
|
|
|
Rank: Administration
Groups: Administration, Customer Joined: 10/24/2006(UTC) Posts: 3,979 Location: Nashville, TN
Thanks: 25 times Was thanked: 89 time(s) in 83 post(s)
|
vladimirb0b wrote:VA and VD are different supplies with a common ground. The capacitance multiplier ramps up within a few seconds according to simulation and multimeter testing, as the most there is is a 47 ohm resistor between supply voltage and the capacitor. A few seconds is far too long. It should be a few tenths. Actually much less would be better. Edited by user Thursday, March 29, 2012 6:55:15 PM(UTC)
| Reason: Not specified
|
|
|
|
Rank: Administration
Groups: Administration, Customer Joined: 10/24/2006(UTC) Posts: 3,979 Location: Nashville, TN
Thanks: 25 times Was thanked: 89 time(s) in 83 post(s)
|
Also VA and VD need to start in synch.
|
|
|
|
Rank: Member
Groups: Member
Joined: 3/21/2012(UTC) Posts: 58
Thanks: 1 times
|
VA is connected to a supply. However, there is almost no voltage at L2, L3, or L4. I'm far from an expert, but wouldn't this suggest a bad voltage regulator? It might matter to the DAC, but it shouldn't matter to the regulator how long it takes to come on.
|
|
|
|
Rank: Administration
Groups: Administration, Customer Joined: 10/24/2006(UTC) Posts: 3,979 Location: Nashville, TN
Thanks: 25 times Was thanked: 89 time(s) in 83 post(s)
|
What is the measured voltage(running) at VA? Edited by user Thursday, March 29, 2012 7:04:56 PM(UTC)
| Reason: Not specified
|
|
|
|
Rank: Member
Groups: Member
Joined: 3/21/2012(UTC) Posts: 58
Thanks: 1 times
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer Joined: 10/24/2006(UTC) Posts: 3,979 Location: Nashville, TN
Thanks: 25 times Was thanked: 89 time(s) in 83 post(s)
|
Thats with everything running?
|
|
|
|
Rank: Member
Groups: Member
Joined: 3/21/2012(UTC) Posts: 58
Thanks: 1 times
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer Joined: 10/24/2006(UTC) Posts: 3,979 Location: Nashville, TN
Thanks: 25 times Was thanked: 89 time(s) in 83 post(s)
|
If your VD supply is capable of supplying the current try just connecting VD to VA and don't use the second supply.
|
|
|
|
Rank: Member
Groups: Member
Joined: 3/21/2012(UTC) Posts: 58
Thanks: 1 times
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer Joined: 10/24/2006(UTC) Posts: 3,979 Location: Nashville, TN
Thanks: 25 times Was thanked: 89 time(s) in 83 post(s)
|
Does there appear to be a short to ground at VRA output with the power off?
|
|
|
|
Rank: Member
Groups: Member
Joined: 3/21/2012(UTC) Posts: 58
Thanks: 1 times
|
Why, yes there does. Resistance dips down to 1.3 Ohms but not stable due to moving voltmeter leads. Not on VRD, however. Edited by user Thursday, March 29, 2012 7:42:49 PM(UTC)
| Reason: Not specified
|
|
|
|
Rank: Administration
Groups: Administration, Customer Joined: 10/24/2006(UTC) Posts: 3,979 Location: Nashville, TN
Thanks: 25 times Was thanked: 89 time(s) in 83 post(s)
|
Interesting, ok, well could be a shorted cap or load or a dead VREG.
|
|
|
|
Forum Jump
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.