xuexucheng
Full Member level 2
Hi, nice guys.
1. As a rule of thumb, the power supply(LDO) should be as close as possible to the circuit. However, since the limitation of PCB area, I must move the power supply to the other PCB and connect the 2 PCBs using very long cables(>2m). I know that we can place lots of decoupling capacitors to keep the power quality. But I want to know is that how to analyze this situation in a quantitative way. i.e. how to caculate?
2. As we know the switch power supply is much noise. If I use this power supply for analog, the noise will be high. Thus, can the LDO be usefull to reduce the noise? How much the noise can reduced? i.e. how to caculate? Is there any other way to reduce the power supply noise effectively?
Thanks in advance.
1. As a rule of thumb, the power supply(LDO) should be as close as possible to the circuit. However, since the limitation of PCB area, I must move the power supply to the other PCB and connect the 2 PCBs using very long cables(>2m). I know that we can place lots of decoupling capacitors to keep the power quality. But I want to know is that how to analyze this situation in a quantitative way. i.e. how to caculate?
2. As we know the switch power supply is much noise. If I use this power supply for analog, the noise will be high. Thus, can the LDO be usefull to reduce the noise? How much the noise can reduced? i.e. how to caculate? Is there any other way to reduce the power supply noise effectively?
Thanks in advance.