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TLC320AD50: TLC320AD50

Aleksandr Petrakov
Prodigy 40 points
Part Number: TLC320AD50

Hello.

I have some technical questions regarding TLC320AD50IDW. Could you help me:
1) As I understood from datasheet - "AVSS" ( lead 26 ) is Analog ground, and "DVSS" ( lead 10 ) is Digital ground. Is it right? If we will supply these leads by  +5V , can we break down the IC?
2) As I understood from datasheet, leads "INM" ( lead 6 ) and "INP" ( lead 5 ) requires an external single-pole antialias filter with a low output impedance. Can we break down the IC if we will supply these leads with out filters?

Great regards, Aleksandr Petrakov

  • 0
    TI__Genius 14540 points

    Hi,

    See answers below.

    1) As I understood from datasheet - "AVSS" ( lead 26 ) is Analog ground, and "DVSS" ( lead 10 ) is Digital ground. Is it right?

    [CY] YES

    If we will supply these leads by  +5V , can we break down the IC?

    [CY] Assuming the phase "break down the IC" here means to break or damage the device, the answer is yes or no.  When you say +5V, it is implied that this is a potential with respect to a reference node, typically, AVSS and/or DVSS.  However, here you are biasing AVSS and DVSS with +5V but with respect to what?  If AVDD and DVDD are +10V, then a +5V AVSS and DVSS should not present a problem.   However, if AVSS is +5V and AVDD is 0V, this would be a problem and violate the absolute maximum specification. I need more information on "supplying these leads by +5V"- +5V with respect to what node(s).

    2) As I understood from datasheet, leads "INM" ( lead 6 ) and "INP" ( lead 5 ) requires an external single-pole antialias filter with a low output impedance. Can we break down the IC if we will supply these leads with out filters?

    [CY] The analog inputs must be AC coupled so that the monitor amplifier works correctly.  This AC coupling cap along with the internal 35kohms form a single-pole filter at the input as shown in Figure 2-16.  Alternatively, a series C, shunt R can be placed externally to provide more design flexibility for the filter response, as shown in Figure 2-17.

    Regards,

    Christian

  • 0 in reply to Christian Yots
    Prodigy 40 points

    Helllo, Christian!

    Thank you for the reply.

    Regarding your 1-st question:

    [CY] Assuming the phase "break down the IC" here means to break or damage the device, the answer is yes or no.  When you say +5V, it is implied that this is a potential with respect to a reference node, typically, AVSS and/or DVSS.  However, here you are biasing AVSS and DVSS with +5V but with respect to what?  If AVDD and DVDD are +10V, then a +5V AVSS and DVSS should not present a problem.   However, if AVSS is +5V and AVDD is 0V, this would be a problem and violate the absolute maximum specification. I need more information on "supplying these leads by +5V"- +5V with respect to what node(s).

    Answer:

    Our customer says he supply leads by:

    AVSS +5V, DVSS +5V, AVDD +5V, DVDD +5V

    Regarding you answer:

    The analog inputs must be AC coupled so that the monitor amplifier works correctly.  This AC coupling cap along with the internal 35kohms form a single-pole filter at the input as shown in Figure 2-16.  Alternatively, a series C, shunt R can be placed externally to provide more design flexibility for the filter response, as shown in Figure 2-17.

    So, can we break the IC if will use it with out any filters before leads "INM" ( lead 6 ) and "INP" ( lead 5 ) ?

    Great regards,

    Aleksandr Petrakov

  • 0 in reply to Aleksandr Petrakov
    TI__Genius 14540 points
    Hi Again,

    AVSS +5V, DVSS +5V, AVDD +5V, DVDD +5V are +5V with respect to some other node at 0V. So long as this other node at 0V, and any other possible 0V nodes, do not get connected to the device there should not be a problem. However, this is highly unlikely as you have a serial port connected to some processor. Surely these lines are biased. Also, inputs and outputs, if DC coupled have some bias. In these cases, this could exceed the absolute maximum specs and potentially damage the device.

    Regarding the filter on the inputs, I don't know if the device will break but there is no guarantee of correct functionality or any of the specs.


    Thanks
    Christian