Page 4 of 5
Re: Tda1387....... the older the fiddle the sweeter the tun
Posted: Sat Sep 24, 2016 12:33 am
by abraxalito
jkeny wrote: I think in 2014 XMOS incorporated an ARM core so these chips are 200mW on 3.3V which using 2400mAh batteries is fine - about 40 hours from fully charged battery
Some kind of irony eh? 200mW is still a fairly thirsty ARM core but perhaps the clock rate is way high (200MHz or so) ?
Ah, assembly code is not for me - OK in small doses, maybe :)
I consider a few hundred lines a 'small dose' yep. Its definitely not for writing user interfaces in.
Re: Tda1387....... the older the fiddle the sweeter the tun
Posted: Sat Sep 24, 2016 12:36 am
by jkeny
abraxalito wrote:jkeny wrote: I think in 2014 XMOS incorporated an ARM core so these chips are 200mW on 3.3V which using 2400mAh batteries is fine - about 40 hours from fully charged battery
Some kind of irony eh? 200mW is still a fairly thirsty ARM core but perhaps the clock rate is way high (200MHz or so) ?
500MIPS but 40 hrs on battery is fine - half that is also fine
Ah, assembly code is not for me - OK in small doses, maybe :)
I consider a few hundred lines a 'small dose' yep. Its definitely not for writing user interfaces in.
Yea, maybe that's borderline OK? :)
Re: Tda1387....... the older the fiddle the sweeter the tun
Posted: Mon Sep 26, 2016 11:15 am
by nige2000
is this the current recommended output handling?
Re: Tda1387....... the older the fiddle the sweeter the tun
Posted: Sun Oct 02, 2016 10:20 pm
by nige2000
an post tracking says i should have a bag of tda1387's tomorrow
so will be able to make up a couple of units for testing
Re: Tda1387....... the older the fiddle the sweeter the tun
Posted: Sun Oct 02, 2016 11:27 pm
by abraxalito
Yep that schematic's still current - I'd add on a trafo at the output to top it off.
I have made a marginal improvement to the bass with my CFB I/V stage over the single transistor shown there. You can get closer to the CFB performance by adding current sources to the transistor - on my version I think I put a pair of 5mA current sources on to bias the I/V transistor up.
Re: Tda1387....... the older the fiddle the sweeter the tun
Posted: Mon Oct 03, 2016 12:22 pm
by nige2000
is tda1387 too old to be nxp branded?
Re: Tda1387....... the older the fiddle the sweeter the tun
Posted: Mon Oct 03, 2016 12:44 pm
by jkeny
nige2000 wrote:is tda1387 too old to be nxp branded?
It seems Philips was sold in 2006 & became known as NXP - don't know if TDA1387 were still being manufactured in 2006?
Are the DAC chips you received not performing?
Re: Tda1387....... the older the fiddle the sweeter the tun
Posted: Mon Oct 03, 2016 5:59 pm
by nige2000
no sounds ok
just nxp branded seems new in a strip of a reel?
tda1387 hardly warrants counterfeiting i assume?
anyway
heres a four stack one
still prefer the acrylic cap 2x1uf on pin 7 more defined bass/detail
after i test functionality of amanero r+/r-, l+/l- ill get on with working on the output
nice gap between usb soekris and tda1387 yet
Re: Tda1387....... the older the fiddle the sweeter the tun
Posted: Wed Nov 30, 2016 12:39 am
by nige2000
nos droop filter
Re: Tda1387....... the older the fiddle the sweeter the tun
Posted: Wed Nov 30, 2016 1:02 am
by nige2000
oh btw put a potato 74374 to reclock on it too, much bigger improvement here than on soekris !