Infineon MA12070 Class D

Jump to Latest
M

maggusxy

Member
Joined 2015
A several months ago, I was working on a project to connect the MA12070P to an ESP32 and use the ESP32 as bluetooth audio receiver.

I just had a look into the code how I implemented the I2C implementation.

Very at the beginning I2C init:
int i2c_master_port = 1;
i2c_config_t conf;
conf.mode = I2C_MODE_MASTER;
conf.sda_io_num = 18;
conf.sda_pullup_en = GPIO_PULLUP_ENABLE;
conf.scl_io_num = 19;
conf.scl_pullup_en = GPIO_PULLUP_ENABLE;
conf.master.clk_speed = 200000;
i2c_param_config(i2c_master_port, &conf);
i2c_driver_install(i2c_master_port, conf.mode, 0,0 , 0);
Click to expand...

Then the I2C write handler function:
esp_err_t i2c_master_write_slave(i2c_port_t i2c_num, uint8_t *data_wr, size_t size)
{
i2c_cmd_handle_t cmd = i2c_cmd_link_create();
i2c_master_start(cmd);
i2c_master_write_byte(cmd, (0x20)<<1 | 0x0, 0x1);
i2c_master_write(cmd, data_wr, size, 0x1);
i2c_master_stop(cmd);
esp_err_t ret = i2c_master_cmd_begin(i2c_num, cmd, 1000 / portTICK_RATE_MS);
i2c_cmd_link_delete(cmd);
return ret;
}
Click to expand...


And then only one command to switch over to I2S input mode:
//set to i2s mode, use the internal sound processor
uint8_t i2cdatax[2] = {0x35, 0x08};
i2c_master_write_slave(1,i2cdatax, 2);
Click to expand...


I even managed to use the bluetooth volume control feedback from the smartphone to control directly the MA12070's internal gain, so that the gain must not ne processed inside the ESP32

The A2Dp bluetooth stack will give you a volume control feedback as a integer number between 0 - 127

uint8_t i2cdataz[2] = {0x40, 127-s_volume};
i2c_master_write_slave(1,i2cdataz, 2);
Click to expand...

If you're interested I can send u the whole ESp32 project - but I developed it with the original ESP-IDF framework. So might be complex when being completely new to uC programming
 
C

commstech

Member
Joined 2002
Onefabis said:
To be more precise, you need to connect speaker wires in that way
Click to expand...

Each set of outputs has their own emc filter. To do mono parallel, do we need to bypass the emc filter of output1a and 1b on the board?

886656d1603385336-infineon-ma12070-class-clip2net_201022194807-png


Infineon-Help-2.jpg
 
daniboun

daniboun

Banned
Joined 2019
Each set of outputs has their own emc filter. To do mono parallel, do we need to bypass the emc filter of output1a and 1b on the board?
Click to expand...

All you need to setup in Mono mode it is to connect speaker wires in the right way, nothing more ) It is a RTR module, easy to configure.

IN0A and IN0B - for the left channel of the mono amp
IN0A and IN0B - for the right channel of the mono amp

IMG-20201011-193730.jpg

IMG-20201011-203332.jpg
 
M

maggusxy

Member
Joined 2015
I'm also a step further with my 4ch output MA12070P DSP powered Amp project.
Just ordered the PCBs this week. Hope to get everything assembled until my christmas holidays starts to use my vacation for the DSP software

merusamp.png


There will be a second PCB which will be attached to the AMP/DSP amp board via the 3 big headers on the front in 90° angle with some push-buttons / rotary encoder and a 2.4" ili9341 LCD screen to control all the DSP settings. The goal is to have it similar like a DCX2496 DSP.

merusamp2.png
 
Last edited:
T

Toku

Member
Joined 2020
daniboun said:
Amplifier is finished and sounds awesome.
1h listening test = fantastic sound stage, really dead silence amp. I will test it more this week but I am really surprised about the amp ) No pop sound, 0 noise.
Click to expand...
This amplifier board also uses a multilayer ceramic capacitor for the audio signal coupling capacitor. Is there any discomfort in the sound quality?

I also ordered two of these amp boards. If the input is an unbalanced connection, connect IN0A-GND and IN1A-GND, and do IN0B and IN1B connect to NC or GND?
 
T

Toku

Member
Joined 2020
Thank you for your advice.

Recently, I started to see amplifiers using multilayer ceramic capacitors, and I was studying by reading the technical information of several Japanese companies.

Thank you for pointing out the problem of unbalanced input. For the time being, I will make an XLR balanced connection and combine it with the SMSL M500.

Toku
 
M

maggusxy

Member
Joined 2015
daniboun said:
That s true Toku. Indeed it uses Ceramic caps and I have to admit that the amplifier sounds great )

Take care : I tested it in unbalanced mode and did not work. Seems that you really need to use it with balanced XLR inputs only....
Click to expand...

Unbalanced mode must work.
The only important thing is to connect the negative input through a decoupling capacitor to GND.

See reference schematic how they did it.
https://www.infineon.com/dgdl/Infin...N.pdf?fileId=5546d462689a790c0168be75a3f0496c
 
T

Toku

Member
Joined 2020
maggusxy said:
Unbalanced mode must work.
The only important thing is to connect the negative input through a decoupling capacitor to GND.

See reference schematic how they did it.
https://www.infineon.com/dgdl/Infin...N.pdf?fileId=5546d462689a790c0168be75a3f0496c
Click to expand...

thank you for the advice.
After checking the circuit diagram of MERUS Evaluation Board MA120 ** EVK again, I understood the input connection. I think the amp board I bought from Aliexpress probably has the same circuit as the EVK, so I'll try it anyway.

Actually, I have already purchased and used 3 SMSL SA300s using MA12070. The sound is better than previous Class D amps, so I wanted to know more about the MA12070 and decided to assemble it from the amp board.
 
T

Toku

Member
Joined 2020
zek said:
Could you specify with which D-class amplifiers it is compared.
Click to expand...
I like the comparative evaluation of Chinese audio equipment and have purchased more than 40 Class D amplifiers so far. Many were unbranded products.
The chips used are TDA7498E, TPA3116D2, TPA3250 to TPA3255, TAS5630, TA2021 and so on.
The brand names are Topping, SMSL, Indeed, Lypy, 3e audio etc.
Of these, the one I am currently using as the main amplifier is a product that uses the TPA3255 TPA3251 MA2070 as the amplifier chip.
 
A

al2813

Member
Joined 2020
I want to go back to the RPI Hat board (KIT_40W_AMP_HAT_ZW). I currently have a player using a RPI4 + an AK4493 DAC Hat purchased in Aliexpress. The quality of the HAT is not too shabby for it's low price (38 euros). I am using the player currently with a set of active speakers I have in my kitchen. Obviously with active speakers you need to go a very high price bracket in order to get decent sound and I am thinking of replacing the speakers with pair of passive ones which you can get pretty decent entry point stuff. This means I will need an amp. I started looking at some amp HATs and encountered the Infineon ones. A few questions:

- has anyone tried the HAT? How does it sound compared to other HAT Amps?
- Messaging is confused about the support of RPI models. I see information stating only RPI zero is supported, and others stating RPI 3 and 4 are also supported. Any idea?
- I understand the Infineon HAT has an integrated DAC. Can I still use my own DAC and use the Infineon as amp only (I think yes as all I need to do is to use the DAC as the sound card in my OS) ?
 
M

maggusxy

Member
Joined 2015
al2813 said:
I want to go back to the RPI Hat board (KIT_40W_AMP_HAT_ZW). I currently have a player using a RPI4 + an AK4493 DAC Hat purchased in Aliexpress. The quality of the HAT is not too shabby for it's low price (38 euros). I am using the player currently with a set of active speakers I have in my kitchen. Obviously with active speakers you need to go a very high price bracket in order to get decent sound and I am thinking of replacing the speakers with pair of passive ones which you can get pretty decent entry point stuff. This means I will need an amp. I started looking at some amp HATs and encountered the Infineon ones. A few questions:

- has anyone tried the HAT? How does it sound compared to other HAT Amps?
- Messaging is confused about the support of RPI models. I see information stating only RPI zero is supported, and others stating RPI 3 and 4 are also supported. Any idea?
- I understand the Infineon HAT has an integrated DAC. Can I still use my own DAC and use the Infineon as amp only (I think yes as all I need to do is to use the DAC as the sound card in my OS) ?
Click to expand...


You don't need any further DAC. The MA12070P is the digital version directly with I2S input. So it connects directly to the digital audio output port of the Raspberry.
The PI-Hat with Merus Amp is also connected via I2C interface to the Raspberry. So you get more or less a device driver where you can even control the amp's internal limiter settings directly in raspbian OS.

However the maximum output power is a little bit limited. The Merus PI Hat connects via a standard USB-C connector to a power-supply (5V input). On board there is a DC/DC boost converter which boosts the 5V up to 20V. They advertise a relativle high-power output, which might be true from theoretical calculation stand-point. However if you want to listen to very bass heavy songs at full output-power it might not be the best choice as the power-capability of the onboard boost-converter will limit the overall output power for sure.

Regarding compatibility - the audio-driver and I2C driver in raspbian OS are abstracted from hardware anyway. The Merus software builts on top of that. So it should be theoretically comaptible with every raspberry.
 
You must log in or register to reply here.
Top Bottom