Hi all,
I'm working on my first project, to build a replacement controller for a set of Monsoon Planar Media 9 speakers. So, there's a bit of a crash-course in electronics happening as well. I'm having a little trouble understanding what I need to supply on one of the controller pins to the mute switch circuit that's on the main board.
The unit uses a TDA8567Q amp. The datasheet at http://www.nxp.com/acrobat_download/datasheets/TDA8567Q_2.pdf shows the mute circuit on page 5. I've looked up the datasheets for all the components, but I'm still a bit lost to explain what all is happening.
I fried the NEC DS882 on the main board that supplies 9V to the controller port hoping that I could simply connect the mute pin wire, 9V+ and GND (yes, probably not the best way to experiment). I'll be replacing the 2SD882 with an NTE184 soon.
The original controller (I don't have one) contains an active crossover for the sub, volume pots, and a mute button with LED. I'm using a Pyramid car crossover on a separate 12V power supply (maybe version 2 of the controller will include a DIY crossover).
I would greatly appreciate some help in understanding how the mute circuit works, and what I need to do in the controller to trigger mute mode (3.3-6.5V @ 30-80uA) and operational mode (>8.5V @ 30-80uA) on the amp. Specifically, some of the questions I'm stuck wondering are:
1. I assume the capacitor plays some role in the amp's recommended 18V/s slope when moving from standby to mute mode, is this accurate? I also don't know how to visualize the effect the capacitor has on the zener. I assume the 3.9V zener must be there to regulate the voltage for mute mode.
2. I'm also having trouble visualizing the effect of the reverse bias diode across the resistor and would like to understand its purpose.
Thanks very much for any help!!!
Best regards
I'm working on my first project, to build a replacement controller for a set of Monsoon Planar Media 9 speakers. So, there's a bit of a crash-course in electronics happening as well. I'm having a little trouble understanding what I need to supply on one of the controller pins to the mute switch circuit that's on the main board.
The unit uses a TDA8567Q amp. The datasheet at http://www.nxp.com/acrobat_download/datasheets/TDA8567Q_2.pdf shows the mute circuit on page 5. I've looked up the datasheets for all the components, but I'm still a bit lost to explain what all is happening.
I fried the NEC DS882 on the main board that supplies 9V to the controller port hoping that I could simply connect the mute pin wire, 9V+ and GND (yes, probably not the best way to experiment). I'll be replacing the 2SD882 with an NTE184 soon.
The original controller (I don't have one) contains an active crossover for the sub, volume pots, and a mute button with LED. I'm using a Pyramid car crossover on a separate 12V power supply (maybe version 2 of the controller will include a DIY crossover).
I would greatly appreciate some help in understanding how the mute circuit works, and what I need to do in the controller to trigger mute mode (3.3-6.5V @ 30-80uA) and operational mode (>8.5V @ 30-80uA) on the amp. Specifically, some of the questions I'm stuck wondering are:
1. I assume the capacitor plays some role in the amp's recommended 18V/s slope when moving from standby to mute mode, is this accurate? I also don't know how to visualize the effect the capacitor has on the zener. I assume the 3.9V zener must be there to regulate the voltage for mute mode.
2. I'm also having trouble visualizing the effect of the reverse bias diode across the resistor and would like to understand its purpose.
Thanks very much for any help!!!
Best regards