Hi,
I bought Aliexpress item number 32872864291 which is this module:
I've seen that since I'm connecting a TPA3116 amplifier to this, that I need to bypass the ground outputs direct to the speakers, only running the live/positive terminals through the relays on the board. This is fine. The issue is that the board stays on the red LED and the green LED won't light and the relays won't activate.
The board is being powered direct from the 24V DC supply that is powering the amplifier.
Fiddling about trying to figure out what was wrong, I disconnected the ground cable on the power connector, and connected one of the speaker grounds through it. The board powered up and after 3 seconds the green LED lit and the relays activated. Trying to figure out why this works, I've noted that this is actually supplying 12V DC to the board. This doesn't work on power up, so it's not a solution, it only works when the amp is already powered up. If I try and power up with this setup, the TPA3116 seems to go into protection mode.
The listing for this says it will work on 12-24v DC. I've no idea why it won't activate with the 24V DC supply. I tried lowering this to the lowest it can go which is 21V DC, and it didn't help.
Looking at the datasheet and there's nothing on there about specifying what voltage it should turn on at, so I believe the fact that the 12V DC using the speaker ground is a red herring.
Has anyone experience with this or a similar module that could shine a light on it?
Thanks
I bought Aliexpress item number 32872864291 which is this module:
I've seen that since I'm connecting a TPA3116 amplifier to this, that I need to bypass the ground outputs direct to the speakers, only running the live/positive terminals through the relays on the board. This is fine. The issue is that the board stays on the red LED and the green LED won't light and the relays won't activate.
The board is being powered direct from the 24V DC supply that is powering the amplifier.
Fiddling about trying to figure out what was wrong, I disconnected the ground cable on the power connector, and connected one of the speaker grounds through it. The board powered up and after 3 seconds the green LED lit and the relays activated. Trying to figure out why this works, I've noted that this is actually supplying 12V DC to the board. This doesn't work on power up, so it's not a solution, it only works when the amp is already powered up. If I try and power up with this setup, the TPA3116 seems to go into protection mode.
The listing for this says it will work on 12-24v DC. I've no idea why it won't activate with the 24V DC supply. I tried lowering this to the lowest it can go which is 21V DC, and it didn't help.
Looking at the datasheet and there's nothing on there about specifying what voltage it should turn on at, so I believe the fact that the 12V DC using the speaker ground is a red herring.
Has anyone experience with this or a similar module that could shine a light on it?
Thanks
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Hi . It looks like this board is not designed for bridge type amplifiers , as they always have half power supply voltage at output ,which are interpretted by protection board as DC ,and board doing its job - protecting speakers . You need a different type protection board ,designed for bridged amplifiers, or you may try make virtual ground, but then you can't use same power supply for protection board and amplifier ,they must be seperate,isolated .
Thanks for the reply, but on posting the image, I realised something didn't look right so I went and checked the board. What has happened is that the seller has sent me a 12-18V version, which won't activate above 18V.
So to change the main question on this thread, is there any UPC1237 experts on here who know how to change the resistors on this to get it to work with 24VDC? I don't understand the datasheet, but it looks like I should only need to change one or two resistors to bring the voltage it is looking for up to 24VDC. Preferably a minimum of 23VDC or something so it has plenty of time to shut down.
So to change the main question on this thread, is there any UPC1237 experts on here who know how to change the resistors on this to get it to work with 24VDC? I don't understand the datasheet, but it looks like I should only need to change one or two resistors to bring the voltage it is looking for up to 24VDC. Preferably a minimum of 23VDC or something so it has plenty of time to shut down.
At first ,try to supply only protection board ,does it activate with no connections to amplifier ?
No, not with 24vdc. It will with 12vdc and I've found the same amplifier for sale on AliExpress that lists that it works with 12-18vdc. I'm fairly confident they've sent me the wrong protection board and I need to change resistors on this to get it to work with 24vdc.
Check voltage at pin4 of upc1237 , it monitors voltage supplied . For higher voltage need to increase resistor from pin6 , to keep relay voltage nominal . But at first , don't connect to amplifier.
It's 4.6V. You where correct though. It's not working correctly as there is a connection from the speaker inputs leading to the chip to do some sort of detection. I snipped the resistors that lead from the speaker cables to the chip, and now it works like I wanted.
Basically my biggest issue was a massive pop on startup, I just needed a delay on time to fix this. The boards work as a delay on now with those resistors removed. I assume the functionality that they provided won't work on a TPA3116 based board anyway?
Basically my biggest issue was a massive pop on startup, I just needed a delay on time to fix this. The boards work as a delay on now with those resistors removed. I assume the functionality that they provided won't work on a TPA3116 based board anyway?
Yes ,such board will offer no protection functionality, only delay, with bridged amps . Here is another thread about protection boards and there was recommended board exactly what you need, for bridged configuration . It contained 2 inputs + - , outputs to speakers , and power supply pins . But power supply still needs to be isolated if i remember properly.
Also ,for tpa3116 is possible to remove turn-on plop by increading resistor or capacitor values on board , ic contains mute pin ,and then you don't need protection board at all .
I know this is an older thread, but wanted to thank you for this solution. I had the exact same use case with a TPA3116 board (XH-M577) and the same protection board, where I just needed a simple startup delay to avoid power-on thump. Clipping the resistors on the input side and running only the positive speaker leads through the relays as you've noted gave me the functionality I needed. Very happy with your solution, thanks!