Hi,
What is the role of R2 in the non-inverting input of this LM3886 schematic from Rod Elliott?
https://sound-au.com/p19_fig2.gif which is in this article Single Chip 50W Stereo Amplifier
Even TI's datasheet has one resistor at the same place
https://www.ti.com/lit/ds/symlink/lm3886.pdf
Thanks and Regards,
WonderfualAudio
What is the role of R2 in the non-inverting input of this LM3886 schematic from Rod Elliott?
https://sound-au.com/p19_fig2.gif which is in this article Single Chip 50W Stereo Amplifier
Even TI's datasheet has one resistor at the same place
https://www.ti.com/lit/ds/symlink/lm3886.pdf
Thanks and Regards,
WonderfualAudio
Per page 8 of the datasheet:
"Prevents currents from entering the amplifier's non-inverting input which may be passed through to the load upon powerdown of the system due to the low input impedance of the circuitry when the under-voltage circuitry is off. This phenomenon occurs when the supply voltages are below 1.5V"
"Prevents currents from entering the amplifier's non-inverting input which may be passed through to the load upon powerdown of the system due to the low input impedance of the circuitry when the under-voltage circuitry is off. This phenomenon occurs when the supply voltages are below 1.5V"
It also mirrors the impedance on the inverting input, cancelling any voltage offset caused by input bias currents.
A trick is missed here, as a small C0G ceramic to ground on the non-inverting input would help attenuate any RF going into the amp chip, forming a low-pass divider with the 1k resistor.
A trick is missed here, as a small C0G ceramic to ground on the non-inverting input would help attenuate any RF going into the amp chip, forming a low-pass divider with the 1k resistor.