The split bobbin frame construction offers better primary to secondary isolation due to low capacitive coupling vs a toroid. It also throws lower magnetic field when having balanced winding vs a basic construction not extra magnetically shielded toroid but its not up to R-Core standards yet which uses a continuous core without magnetic gaps and corners. All in all this low profile PCB mounting Hammond series is a good enough choice vs plain EI or plain toroidal but its lack of direct to chassis mounting options should be also kept in mind.
Thanks Salas. As for the transformer mounting...I am assuming that machine screws with standoffs would be used through the 2 holes provided in the core to mount the transformer to the chassis. When doing this would it be best to use nylon standoffs as to electrically isolate the transformer core from the chassis?
Do you know of a source for R-Core transformers that would suit my application? I did a little searching around and found this supplier in the US.
R-Core Transformer Dimensions - North Manchester, Indiana
Do you know of a source for R-Core transformers that would suit my application? I did a little searching around and found this supplier in the US.
R-Core Transformer Dimensions - North Manchester, Indiana
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It would take aluminum or nylon screws not to affect the magnetic circuit. All associated mounting hardware should be non ferromagnetic too when attempting mounting through the core. Only two in line mounting points with light material screws wouldn't travel well for instance but for stationary use they should be secure enough supporting a small transformer.
Those R-Core of American distribution you linked are arguably the best you can currently find. They are the same Indian manufactured ones that were available in Europe from Selectronic France before they closed shop. Someone new must hopefully resume their distribution in EU also because it was a shame to see them go.
Shilchar Technologies Ltd.
Those R-Core of American distribution you linked are arguably the best you can currently find. They are the same Indian manufactured ones that were available in Europe from Selectronic France before they closed shop. Someone new must hopefully resume their distribution in EU also because it was a shame to see them go.
Shilchar Technologies Ltd.
Oscillation trouble when powering a TPA Mercury i/V
Hi Salas,
I am running a BIB SSLV 1.1 at +-15 V powering a TPA Mercury I/V.
As the I/V boardy is decoupled with 2 x 330 uF capacitors on both negative and positive leg these cause my SSLV to oscillate. Since I have no oscilloscope the only test I perform is check for AC at the output of the regulator. I observe 100+ mv AC with caps on , and 13mv AC with caps removed.
The SSLV is configured with 10uF MKS Wima C201/C101 and 4uF MKS Wima C103/203. What is your advice as I want to keep this regulator?
Thx,
Abraham
Hi Salas,
I am running a BIB SSLV 1.1 at +-15 V powering a TPA Mercury I/V.
As the I/V boardy is decoupled with 2 x 330 uF capacitors on both negative and positive leg these cause my SSLV to oscillate. Since I have no oscilloscope the only test I perform is check for AC at the output of the regulator. I observe 100+ mv AC with caps on , and 13mv AC with caps removed.
The SSLV is configured with 10uF MKS Wima C201/C101 and 4uF MKS Wima C103/203. What is your advice as I want to keep this regulator?
Thx,
Abraham
Try 1R to 10R 1/4W resistors in series with the +V & -V PSU inputs at the TPA. To create RC with those 330uF and "buffer" the reg. Also two wire connection mode instead of Kelvin may help if the phenomenon does not reduce enough with that fix in case its also a matter of longish sense wires and EMI pickup by them. See a relative link in post #1 here on how to utilize two wire classic connection mode for this reg.
Hello Salas. Are these the currently recommended LEDS for use with the SSLV1.1?
wp2773 Kingbright Standard LEDs - Through Hole | Mouser
If so which ones are to be used as the 1.9V and 2.1V as called out in the Excel Calculator? The data on the Mouser page says the yellow ones are 2.1V but none of the others spec at 1.9V as called for in the Excel calculator.
Do you have a preferred brand type and wattage for the various resistors on the boards? I did see a post where I see you were using a Caddock MP series for R101.
Lastly, I am planning on building a two box system with the transformers housed in a separate aluminum box connected with an umbilical. Would you recommend also building the bridge rectifier and C105 filter capacitor into the remote box along with the transformers?
wp2773 Kingbright Standard LEDs - Through Hole | Mouser
If so which ones are to be used as the 1.9V and 2.1V as called out in the Excel Calculator? The data on the Mouser page says the yellow ones are 2.1V but none of the others spec at 1.9V as called for in the Excel calculator.
Do you have a preferred brand type and wattage for the various resistors on the boards? I did see a post where I see you were using a Caddock MP series for R101.
Lastly, I am planning on building a two box system with the transformers housed in a separate aluminum box connected with an umbilical. Would you recommend also building the bridge rectifier and C105 filter capacitor into the remote box along with the transformers?
Those Kingbright are more predictable for Vf sample by sample than various generics I have measured, that's their good thing. Their yellow ones will be nearer to 1.9V at the current levels they are likely to see in this circuit. Mouser lists Vf at test condition If=20mA as in the datasheet i.e. nominal.
Caddock MP series is good for R101. Other resistors places are not sensitive for power or special quality. Just use 100ppm metal film 1/4 or 1/2W.
Yes you can do that i.e. house the rectification and main reservoir separately along with the trafos so the umbilical carries DC and does not radiate a field but put a 220uF 40V capacitor where the original C105's place was on the reg's PCB because the incoming umbilical cable will need decoupling. Else there will be noise.
Caddock MP series is good for R101. Other resistors places are not sensitive for power or special quality. Just use 100ppm metal film 1/4 or 1/2W.
Yes you can do that i.e. house the rectification and main reservoir separately along with the trafos so the umbilical carries DC and does not radiate a field but put a 220uF 40V capacitor where the original C105's place was on the reg's PCB because the incoming umbilical cable will need decoupling. Else there will be noise.
Salas. Let me clarify please on the LEDS. The yellow ones are to be used in the 1.9V positions as called for on the excel calculator D104, D105 in my case? Which ones would be used the 2.1V positions D102A, D102B, D103 and D104 in my case?
For the 220uF decoupling cap would the Nichicon KZ elecrolytic be a good choice or better with a Mundorf Mlytic AG?
For the 220uF decoupling cap would the Nichicon KZ elecrolytic be a good choice or better with a Mundorf Mlytic AG?
Greens should do nearer 2.1V in the row of four positions.
If you don't care spending double on AGs you can repeat the first reservoir on the reg and double your uF total plus the umbilical's little resistance will create a CRC EMI filter as a side benefit. But just locally decoupling with a KZ is not an intrinsically problematic solution either.
If you don't care spending double on AGs you can repeat the first reservoir on the reg and double your uF total plus the umbilical's little resistance will create a CRC EMI filter as a side benefit. But just locally decoupling with a KZ is not an intrinsically problematic solution either.
