TI engineers,
I tested the power of DM6446,and I found the entire part of power had some noise(a lot of glitch),including the power of 5V、3.3V、1.8Vand 1.2V. My power conversion chip is AIC 1084-1.8CM、AIC 1084-1.8CM and TI power conversion chip TPS54312.
When I found the noise problem, I tried to add the filter circuit, but it hadn't any effect. Then,I tried to connect the power(1.8V and 1.2V) to DM6446 on by one. Surprisingly, I cut off the output of TPS54312 to DM6446, then the noise hadn't appear.But, the power had niose when I added the power of 1.2V.
I used the resistance of 200 ohm as the load of TP54312, and the result is same as cutting off 1.2V, the power hadn't noise.
I tested the static state resistance of the port of 1.2V and GND of DM6446, and the value is less than 200 ohm, and only about 100 ohm.
I think the niose caused the chip of DM6446 heated abnormally, and the smaller resistance of DM6446 also affect the chip temperature when the power is supplied.
I don't konw how to solve the noise problems and is it the reason of heated? I need your help. Thank you!
min
