SSLV1.1 builds & fairy tales

[merlin el mago]

Salas I use BiB BJT for 3.3 Vout D105 LED don't lit and Atlas DCA55 is gone so can't check the semis, how can do to fix?

TIA
Felipe

 

[Salas]

You can check BJTs by correct Vbe when power is on, Mosfets by correct VGS when power is on, JFETs by correct RDS when power is off. Leds with light up check from a battery.

 

[merlin el mago]

My fault D105 is reversed

 

[Salas]

Devil is in the details

 

[merlin el mago]

Now is working solid as a rock

 

[Salas]

Atlas needs a new battery or one of its clips cut out at cable's end because of use strain?

 

[merlin el mago]

Devil is in the details

Always.

 

[merlin el mago]

Atlas needs a new battery or one of its clips cut out at cable's end because of use strain?

The device told me to change the battery, once changed display said:

"Self test failed: CODE: 6"

Contacted Atlas and answer was: "Code 6 indicates that one of the multiplexers has probably been damaged.

Your DCA55 will be the same circuit as the picture I sent you, so it is most likely that the analog switch U5 has failed.
You can either send the DCA55 to us to be repaired, which can be ordered in our Web shop, or you can try to repair it yourself by replacing U5, although I cannot guarantee that this will solve the problem.

If we repair it then you can be sure it is working, and the repair comes with a new 12 month warranty. "

Attached image IC to be changed.

 

[Salas]

Well detailed answer by the manufacturer. That chip must be low cost to try replace it yourself before sending the device to them even if its not the 100% right failure guess (unlikely).

 

[merlin el mago]

Farnell don't have SMT have this one Texas Instruments with the same reference, is OK?

CD74HC4051E TEXAS INSTRUMENTS, IC, 74HC, 74HC4051, DIP16, 6V | Farnell element14 Espana

 

[Salas]

Better email Peak Instruments for guidance about that Farnell link and right choice

 

[merlin el mago]

Ok

 

[merlin el mago]

Received advice from Jeremy of Peak Electronic to use this one:

74HC4051D NEXPERIA, Multiplexor / Demultiplexor Analogico, 8:1, 1 Circuito, 2V a 10V, SOIC-16 | Farnell element14 Espana

 

[Salas]

Good luck with the repair then

 

[merlin el mago]

Many thanks Salas, I will let you know how will finish the reparation.

 

[wcwc]

For a 5V output is it better to use this regulator or the ReflectorD?

 

[Salas]

If it is for powering digital stuff the REF-D is usually more predictable

 

[wcwc]

Yes, it is for DACs, clock board, and DSP. So I will pick up another ReflectorD.

 

[wcwc]

I have a set of positive and negative power supply boards. I am shooting for a 9V output to 3 DACs. Positive supply would have a CCA of 750 mA. Negative would be 400mA. When picking out a transformer would a transformer with 15V secondaries work? The documentation said I needed to supply greater Vac than the Vdc I was looking to get.

 

[AndrewT]

For normal series regulators:
9Vac might do for a +-9Vdc regulator.
But this might reach drop out as the mains drops to lowest tolerance.
Play safe and go for a pair of 10Vac secondaries.
If you can't source 10Vac, then go up to 12Vac.

15Vac will make the regulators run too hot, since the input would be around 22Vdc

But shunt regulators need a higher volts drop across the current limiting section.
eg. the +-10Vdc from the shunt regulators of the DCB1 needed at least 13Vac secondaries, so we ended up using 15Vac.