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TIDA-060001: TIDA-060001 for DC48V Bus

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Replies: 7

Views: 135

Part Number: TIDA-060001

Hello,

my problem is that the User Guide don't give enough information about the DC-Bus coupling.

It is referencing on page 16 on the design of tidu167 where I was told that the design is too old and had been taken down and I should look for TIDA-060001but that is more focused on the AC coupling. Furthermore I noticed on page 19 Figure 26 a mistake that the schottky and zener diode have the same schematic symbol which will confuse the user. It would be great if the figure and the schematic get fixed.

I would like to communicate over a 48V DC-Bus where a max amperege of 3A can exist. I would like to communicate in the Cenelec C Band with the main frequency of 131,25 Khz.

I tried to make an schematic for the plc communication but there are some points where I can't find any information about it.

Here is a picture of the schematic which I made. I marked some components where I didn't find anything or I am unsure if I chosed the right parameter.

Also do I need a HV Capacitor (C4) with a higher Voltage rating (48V+ amplified signal) ?

Greetings Patrick

  • Hello Patrick,

    Thank you for your post. Our engineer handling this is out of office at the moment, we will have another team member support you shortly. 

    -Tamara

  • In reply to Tamara M Alani:

    Hello Patrick,

    Here is what I have per your request:

    1. L2 and C3 passive band pass filters, C3=1nF, L2=1mH and I added a resistor in series with L2 to deque the peak, see the attached TINA Simulation.

    2. C7=10nF, approx. 122Ohm at 131kHz to the input filter.

    3. C8=10nF, same as reference drawing (SBOA130A Revised Nov., 2011 Application Report)

    4. C1=2.2uF, input filter capacitor to the TPS62177 regulator or similar.

    5. D1 may be 20-25V zener (the symbol indicates as zener, different from D2 and D3) 

    6. C9 is used blocking DC, reference design is shown 3.3nF (SBOA130A Revised Nov., 2011 Application Report)

    7. R5 is shown 0.5Ohm. If you intend to operate at 3A maximum, it will dissipate 1.5W. 

    If you have other questions, please let me know. 

    Passive Band-Pass Filter in Forum 10142019-2.TSC

    Regards,

    Raymond

  • In reply to Tamara M Alani:

    Hello Patrick,

    Here is what I have per your request:

    1. L2 and C3 passive band pass filters, C3=1nF, L2=1mH and I added a resistor in series with L2 to deque the peak, see the attached TINA Simulation.

    2. C7=10nF, approx. 122Ohm at 131kHz to the input filter.

    3. C8=10nF, same as reference drawing (SBOA130A Revised Nov., 2011 Application Report)

    4. C1=2.2uF, input filter capacitor to the TPS62177 regulator or similar.

    5. D1 may be 20-25V zener (the symbol indicates as zener, different from D2 and D3) 

    6. C9 is used blocking DC, reference design is shown 3.3nF (SBOA130A Revised Nov., 2011 Application Report)

    7. R5 is shown 0.5Ohm. If you intend to operate at 3A maximum, it will dissipate 1.5W. 

    If you have other questions, please let me know. 

    7384.Passive Band-Pass Filter in Forum 10142019-2.TSC

    Regards,

    Raymond

  • In reply to Raymond Zhang1:

    Hi Patrick,

    Missed your last question - Also do I need a HV Capacitor (C4) with a higher Voltage rating (48V+ amplified signal) ?

    You do not need the HV rating shown in Table 6 in SOBOA130A application note. However, I will suggest to have low ESR with rated 100V (minimum) ceramic capacitor.  

    Regards,

    Raymond

  • In reply to Raymond Zhang1:

    Hi Patrick,

    Here is the link for the AFE031 PLC Application Note: http://www.ti.com/lit/ds/symlink/afe031.pdf

    When I replied to  your questions, I was looking at the previous application note, dated back in 2011. I realized my mistakes, thus, I am going to revise some of my answers.  

    1. L2 and C3 passive band pass filters, C3=1nF, L2=1mH and I added a resistor in series with L2 to deque the peak, see the attached TINA Simulation.

    L7 inductor is not shown in Figure 48 on p.47 of AFE031 application note. I do not know the purpose of L7. Also, C5=1000pF, but reference design is shown 10nF. Please verify these with the reference design, see p.29 about the recommended values and calculation. 

    2. C7=10nF, approx. 122Ohm at 131kHz to the input filter.

    This section is shown in Figure 31, p.28 of AFE031. The calculated value is much lower. I will go with the reference design in Figure 48 on p.47.  

    3. C8=10nF, same as reference drawing (AFE031, June, 2019)

    4. C1=2.2uF, input filter capacitor to the TPS62177 regulator or similar.

    5. D1 should be 25V schottky, though zener will work also. It is not on during normal operation. It is used for transient protection.  

    6. C9 is used blocking DC, reference design is recommended 1nF (AFE031, June, 2019)

    The explanation is shown on p. 27 in Figure 30 and Table 2. Please copy the reference design. 

    7. R6 is shown 0.5Ohm. If you intend to operate at 3A maximum, it will dissipate 4.5W (my oversight).  

    8. I do not understand the use of 680uH, L1 and R6 at the input of LM5165 converter. Are you able to send us 48V/3A part of DC-bus schematic? 

    Regards,

    Raymond 

  • In reply to Raymond Zhang1:

    Raymond Zhang1

    Hi Patrick,

    Here is the link for the AFE031 PLC Application Note: http://www.ti.com/lit/ds/symlink/afe031.pdf

    When I replied to  your questions, I was looking at the previous application note, dated back in 2011. I realized my mistakes, thus, I am going to revise some of my answers.  

    1. L2 and C3 passive band pass filters, C3=1nF, L2=1mH and I added a resistor in series with L2 to deque the peak, see the attached TINA Simulation.

    L7 inductor is not shown in Figure 48 on p.47 of AFE031 application note. I do not know the purpose of L7. Also, C5=1000pF, but reference design is shown 10nF. Please verify these with the reference design, see p.29 about the recommended values and calculation. 

    2. C7=10nF, approx. 122Ohm at 131kHz to the input filter.

    This section is shown in Figure 31, p.28 of AFE031. The calculated value is much lower. I will go with the reference design in Figure 48 on p.47.  

    3. C8=10nF, same as reference drawing (AFE031, June, 2019)

    4. C1=2.2uF, input filter capacitor to the TPS62177 regulator or similar.

    5. D1 should be 25V schottky, though zener will work also. It is not on during normal operation. It is used for transient protection.  

    6. C9 is used blocking DC, reference design is recommended 1nF (AFE031, June, 2019)

    The explanation is shown on p. 27 in Figure 30 and Table 2. Please copy the reference design. 

    7. R6 is shown 0.5Ohm. If you intend to operate at 3A maximum, it will dissipate 4.5W (my oversight).  

    8. I do not understand the use of 680uH, L1 and R6 at the input of LM5165 converter. Are you able to send us 48V/3A part of DC-bus schematic? 

    Regards,

    Raymond 

    Hello Raymond,

    thank you for your fast response. I took the 680uH for L1 from the reference design of http://www.ti.com/lit/ug/tidue68/tidue68.pdf (TIDA-060001)

    on page 16 Figure 18. I read that the inductor impedance must be higher than the plc impedance so that the plc signal wouldn't interfere with the LM5165.

    R6 should simulate my contact point to the dc bus which has a resistance of 0.5 ohm.

    My schematic need to be updated now with the new information which will take some time.

    I am very thankful by your support.

    Greetings Patrick

  • In reply to Patrick Zahn:

    Hi Patrick,

    Yes, You are good.

    Normally inductor should not be added at the input of DC converter. Your schematic is showing the receiving end of DC power transfer. Without the inductor, PA may be unable to transmitting the modulated AC signals due to the low output impedance. Therefore, the inductor of 680uH is inserted, which AC impedance is increased to 2*pi*f*680uH. At 131 kHz, the impedance is approx. 560Ohms. However, you should never plug/unplug the PLC lines while these modules are powered. 

    Regards,

    Raymond