I followed the tech. info which is linked at the Farnell item site. And of course your PDF.
Question is: is it OK that pin 2+3 are measure the same but different on the "+" and "-" side of the SSR03?
At Vout + and - I get 15,8V. Where does the difference to 15V comes from?
If you have the same voltage on pin 2 and 3, that means you have a working feedback. The LM329 has a tolerance and aslo the resistors, therefore you will have a small difference in output voltage. If you get 15.8 volts instead of 15.0 V, it is tolerances. If you had chosen the LM431 you would have gotten a better result.
OK, thank you.
But on the other side my understanding is that the 329 is less noisier than the 431. Is this right?
OK, that means: YES The 431 is more flexible but noisier than the 329.
Are there any other things to consider when deciding on 431or 329?
You had suggested testing the SSR03 with a load resistor. Could you give me a basic recommendation as to what I should be aware of and what is worthwhile?
Am I right I nned two: connecting Vout+ and ground; connecting Vout- and ground
Thank you
Are there any other things to consider when deciding on 431or 329?
You had suggested testing the SSR03 with a load resistor. Could you give me a basic recommendation as to what I should be aware of and what is worthwhile?
Am I right I nned two: connecting Vout+ and ground; connecting Vout- and ground
Thank you
As a load you use Ohm's law R = U/I 100 mA could be a suitable test current.
If you use a LM329 then you have a higher limit for the lowest output voltage. As I told you the noise is of no importance since you remove all noise with a filter. The opamp stands for 100% of the noise if you have seen the measurement done by jackinnj.
If you use a LM329 then you have a higher limit for the lowest output voltage. As I told you the noise is of no importance since you remove all noise with a filter. The opamp stands for 100% of the noise if you have seen the measurement done by jackinnj.
SSR03 usecase
I will use the SSR03 for 3x analouge X-over. The power supply for them is rated with:
15 – 17V and
5VA each
I also will use a SSR03 for a Class-A DCG3 PreAmp which is rated with:
16 – 17V and
30 – 50W
Is it a praktical usecase to use one 17V SSR03 for 3x X-over and the DCG3 class-A PreAmp?
What is a reasonable limit of mA for an SSR03?
According to your SSR03 BOM the different between a Volts equal 431 and 329 are:
R31/32 and VR1/2 are different and
R39/40, R43/44, R45/46 are new
According to the P1/2 Trimpoti:
They are mentioned in the PDF. But I do not find them within your BOM.
Where do I find techn. infos / parameters for the P1/2 trimpotentiometer?
From your website:
„The reference (positive side)
…. The LM431 (thick outline in the silkscreen print) has four resistors R39, R41, R43, R45 (R40, R44, R46) and a trimpotentiometer P3 in order to trim the reference voltage. You can't trim the LM329.
The feedback network (positive side)
The feedback network is R25+R27 as the upper part. R25 is normally a wire and is used for trimming purposes. R31 in parallel of R33 is the lower part of the feedback and R31 is for trimming also. P1 can also be used if you want a variable output voltage, recommended if you use a fixed voltage reference like the LM329.“
Do these statements not oppose each other?
Last question:
BOM for 15V and 18V are available, but perhaps I do need 17V (see above):
Am I right taking a 431 SSR03 in that case and using the P1/2 trimpotentiometer to get the 17V. Is the 15V or 18V SSR03 the PSU to get 17V? Or do I even need a new BOM?
Thank you for your attantion
I will use the SSR03 for 3x analouge X-over. The power supply for them is rated with:
15 – 17V and
5VA each
I also will use a SSR03 for a Class-A DCG3 PreAmp which is rated with:
16 – 17V and
30 – 50W
Is it a praktical usecase to use one 17V SSR03 for 3x X-over and the DCG3 class-A PreAmp?
What is a reasonable limit of mA for an SSR03?
According to your SSR03 BOM the different between a Volts equal 431 and 329 are:
R31/32 and VR1/2 are different and
R39/40, R43/44, R45/46 are new
According to the P1/2 Trimpoti:
They are mentioned in the PDF. But I do not find them within your BOM.
Where do I find techn. infos / parameters for the P1/2 trimpotentiometer?
From your website:
„The reference (positive side)
…. The LM431 (thick outline in the silkscreen print) has four resistors R39, R41, R43, R45 (R40, R44, R46) and a trimpotentiometer P3 in order to trim the reference voltage. You can't trim the LM329.
The feedback network (positive side)
The feedback network is R25+R27 as the upper part. R25 is normally a wire and is used for trimming purposes. R31 in parallel of R33 is the lower part of the feedback and R31 is for trimming also. P1 can also be used if you want a variable output voltage, recommended if you use a fixed voltage reference like the LM329.“
Do these statements not oppose each other?
Last question:
BOM for 15V and 18V are available, but perhaps I do need 17V (see above):
Am I right taking a 431 SSR03 in that case and using the P1/2 trimpotentiometer to get the 17V. Is the 15V or 18V SSR03 the PSU to get 17V? Or do I even need a new BOM?
Thank you for your attantion
Last edited:
Up to 700 mA is possible with some changes but you will most likely need more cooling.
The trim pot is a place holder so use it if you think it's convenient. The type can be found in the BOM for the whole design but the value may not be correct for your purposes.
The P1 can be used for trimming the gain and the P3 for trimming the reference voltage if you have that kind of reference.
I recommend that you use the 15 V BOM and trim the LM431 in the R45 position. You have the formula at my homepage but if it makes it easier for you, calculate for 8.5 V reference voltage, assuming that the gain is set to 2.
The trim pot is a place holder so use it if you think it's convenient. The type can be found in the BOM for the whole design but the value may not be correct for your purposes.
The P1 can be used for trimming the gain and the P3 for trimming the reference voltage if you have that kind of reference.
I recommend that you use the 15 V BOM and trim the LM431 in the R45 position. You have the formula at my homepage but if it makes it easier for you, calculate for 8.5 V reference voltage, assuming that the gain is set to 2.
Am I right saying the PSU is capable delivering roughly 10W@17V?
If so that is not enough to feed the DCG3 (20-30W@17-18V) preamp. but enough for the x-overs (5-7W@15-17V) as originally planned ;-) It is certainly not enough for both together, as I had considered the last days.
But thats fine
I am preparing the order for 2x 17V-LM431 (for the DCG3 preamp) and 1x 5V-LM431 (for the analogue dam1121 part) SSR-03.
The difference are small:
* At 17V I see eight resistors more.
* Is 5V-LM431 BON correct that DZ1+2 and H1+2 are red LED's?
* 17V-BOM said DZ1+2 are Zener diodes and H1+2 are LED's
The difference are small:
* At 17V I see eight resistors more.
* Is 5V-LM431 BON correct that DZ1+2 and H1+2 are red LED's?
* 17V-BOM said DZ1+2 are Zener diodes and H1+2 are LED's
Hi !
May I have 2 boards with soldered AD825 ?
Shipping to FRANCE.
Supa thanxs.
Best from the Alps.
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