Purpose of the decoupling caps
Hi
Just found a reference for the TDA1541A:
IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. SC-21, NO. 3, JUNE 1986
A Monolithic Dual 16-Bit D/A Converter
HANS J. SCHOUWENAARS, EISE CAREL DIJKMANS, BEN M. J. KUP, AND ED J. M. VAN TUIJL
According to this paper, the seven decoupling capacitors are used as low-pass filters to remove a 250 kHz oszillator frequency that is used to obtain constant MSB bit currents by dynamic current division.
This procedure is used for bits 11 - 16.
Martin
Hi
Just found a reference for the TDA1541A:
IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. SC-21, NO. 3, JUNE 1986
A Monolithic Dual 16-Bit D/A Converter
HANS J. SCHOUWENAARS, EISE CAREL DIJKMANS, BEN M. J. KUP, AND ED J. M. VAN TUIJL
According to this paper, the seven decoupling capacitors are used as low-pass filters to remove a 250 kHz oszillator frequency that is used to obtain constant MSB bit currents by dynamic current division.
This procedure is used for bits 11 - 16.
Martin
Some advice from own experience: don't use tantalum capacitors for DEM clock decoupling. They are sensitive to mechanical stress and vibration, and that directly appears on the analog output signal. I tried such capacitors on pins 12,13 and 18,19, then I had to revert to polyester (WIMA MKS-4 0.68uF).
Just wanted to tell my story so far.
Got a Marantz CDA-94.
Did some recapping and replaced decoupling caps with 2.2uF ERO green axial MKT on MSB pins and 0.47uF Vishay axial MKP on the rest.
Both have excellent values and the old MKTs give a very pleasant sound in many applications.
Thing is, now the sound is very good, but very soft.
I like soft, I am sensitive to harsh sound.
So I am afraid that this sound is insanely soft for real!
When comparing to a Burson HA-160D with ES9018 I cannot find anything lacking from the Marantz, but the Burson is clearer. Pretty much same thing with my tubed BlueNote Koala.
I will sell the Burson at some point, but I need something equally good to keep
Do others have similar experience, bigger cap = softer sound in this case?
Got a Marantz CDA-94.
Did some recapping and replaced decoupling caps with 2.2uF ERO green axial MKT on MSB pins and 0.47uF Vishay axial MKP on the rest.
Both have excellent values and the old MKTs give a very pleasant sound in many applications.
Thing is, now the sound is very good, but very soft.
I like soft, I am sensitive to harsh sound.
So I am afraid that this sound is insanely soft for real!
When comparing to a Burson HA-160D with ES9018 I cannot find anything lacking from the Marantz, but the Burson is clearer. Pretty much same thing with my tubed BlueNote Koala.
I will sell the Burson at some point, but I need something equally good to keep
Do others have similar experience, bigger cap = softer sound in this case?
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