ISO7720: Output Current

Mark Millison

Part Number: ISO7720

What is the max current that the output can safely provide? The data sheet specifies an absolute max of 15mA but no one wants to use this limit. Under the recommended operating conditions it does not specify a max output current. Can the part drive 12mA without damaging the part? Can it drive 10mA without damaging the part?

Thanks--Mark

over 6 years ago

0 Lucas Schulte9 over 6 years ago

TI__Expert 6955 points

Mark,

Typically most TI digital isolators can only output a maximum of 4mA under normal operating conditions. Please refer to the linked thread below. Please feel free to post any further questions.

e2e.ti.com/.../2787065

Respectfully,

Lucas

0 Lucas Schulte9 over 6 years ago in reply to Lucas Schulte9

TI__Expert 6955 points

Mark,

Also section 6.3 Recommended Operating Conditions of the datasheet contains this information. The figure above shows the max/min of the low/high-level output currents. The output schematic also helps clarify the architecture used for sourcing/sinking current of the outputs.

Respectfully,

Lucas

0 Mark Millison over 6 years ago in reply to Lucas Schulte9

Prodigy 90 points

Thanks Lucas. The datasheet only specifies the min current and not the max current in section 6.3. Perhaps the data sheet could be updated?

Thanks--Mark

0 Mark Millison over 6 years ago in reply to Lucas Schulte9

Prodigy 90 points

Is the 4mA only with the 5V supply input?

0 Lucas Schulte9 over 6 years ago in reply to Mark Millison

TI__Expert 6955 points

Mark,

The datasheet does show the maximum current for the output pins but its just presented in a weird way. Current for outputting a logical high is shown to be -4mA and therefore listed as a minimum on a technicality. Understand that current flow is referenced in relation to the IC and negative current is thought of as current leaving the IC. It's the opposite for outputting a logical low where current sinks into the device to flow to ground. Either way, the absolute value of the max operating current that can be handled by the outputs is 4mA. Does this help clarify the min/max current values?

Respectfully,
Lucas

0 Lucas Schulte9 over 6 years ago in reply to Mark Millison

TI__Expert 6955 points

Mark,

Yes this is correct.

Respectfully,
Lucas

0 Mark Millison over 6 years ago in reply to Lucas Schulte9

Prodigy 90 points

Thanks for all the help Lucas!

Mark

Isolation

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ISO7720: Output Current