EFD20 Bobbin?
in [Design]
|
Prev: Laser Diode Driver IC with analog modulation capability up to2Ghz ?
Next: Another Obama attempt at controlling the Internet...
From: Hammy on 7 May 2010 08:27 I'm trying to wind 3 x 26AWG twisted on a EFD20 bobbin and it's really a PITA. Would there be a significant increase in winding capacitance if I just use single strands in parallel? The rms current in the primary is 2.2A primary turns of 9. It's for a 15W flyback.
From: mook johnson on 7 May 2010 08:33 "Hammy" <spam(a)spam.com> wrote in message news:pm18u5t0hupdgdb79cfk0qlhl462bro0p2(a)4ax.com... > > > I'm trying to wind 3 x 26AWG twisted on a EFD20 bobbin and it's really > a PITA. Would there be a significant increase in winding capacitance > if I just use single strands in parallel? The rms current in the > primary is 2.2A primary turns of 9. It's for a 15W flyback. Switching frequency?
From: Hammy on 7 May 2010 09:45 On Fri, 7 May 2010 07:33:13 -0500, "mook johnson" <mook(a)mook.net> wrote: > >"Hammy" <spam(a)spam.com> wrote in message >news:pm18u5t0hupdgdb79cfk0qlhl462bro0p2(a)4ax.com... >> >> >> I'm trying to wind 3 x 26AWG twisted on a EFD20 bobbin and it's really >> a PITA. Would there be a significant increase in winding capacitance >> if I just use single strands in parallel? The rms current in the >> primary is 2.2A primary turns of 9. It's for a 15W flyback. > >Switching frequency? > > Whoops sorry it's 100kHz.
From: Bill Sloman on 7 May 2010 10:25
On May 7, 2:27 pm, Hammy <s...(a)spam.com> wrote: > I'm trying to wind 3 x 26AWG twisted on a EFD20 bobbin and it's really > a PITA. Would there be a significant increase in winding capacitance > if I just use single strands in parallel? The rms current in the > primary is 2.2A primary turns of 9. It's for a 15W flyback. The usual arguement for using twisted wire to widn a transformer is to minimise the leakage inductance (not capacitance) and to make the three windings involved as nearly identical as possible (to one part in more than ten million, if you do it right - which is of interest in ratio transformers, and pretty much irrelevant for the windings of a flyback converter). I wouldn't have though that it would have made much difference to the inter-winding capacitance; twisting the wires will mean that they will be - on average - a little further apart that wires laid in parallel, but that isn't going to make much of a difference. -- Bill Sloman, Nijmegen |