ISO6740-Q1: ISO6740QDWRQ1

Kiranmayi Prasada

Part Number: ISO6740-Q1

ISO6740QDWRQ1 is used in our design as shown below, the sense signals(INx and OUTx) are of 5V level and VCC=3.3V. According to the datasheet INx and OUTx maximum voltage rating is VCCx+0.5, but we wanted to know if INx and OUTx signals are 5V tolerant or we need to level translate sense signals in our schematic to 3.3V?

Thanks

over 2 years ago

0 Amit Jagtap over 2 years ago

Intellectual 560 points

Adding information to above querry - The VCCx absolute maximum voltage is 6V, as per data sheet. So if VCC is biased with 3.3V. Then whether input supports 5V level input signals. (Whether inputs are 5V tolerant)

0 Andrew Jackiw over 2 years ago

TI__Mastermind 20855 points

Hello Kiranmayi,

Operating outside the conditions in Table 7.1 Absolute Maximum Ratings (attached below for convenience) will cause device damage. As you have stated the datasheet INx and OUTx maximum voltage rating is VCCx+0.5, exceeding this could damage the device.

Please also note that VCCI and VCCO do not have to be the same voltage and are completely independent, so there may not be a need to level shift separately. More information here.

I hope this helps.

Best,

Andrew

0 Kiranmayi Prasada over 2 years ago in reply to Andrew Jackiw

Prodigy 40 points

Thank you Andrew, so with supply voltage 3.3V we cannot connect 5V level input signal to INx as it may damage the device. Hope i inferred it correctly?

+1 Andrew Jackiw over 2 years ago in reply to Kiranmayi Prasada

TI__Mastermind 20855 points

Kiranmayi,

Your understanding is correct. With a 3.3V supply, 5V level input signal to INx may damage the device. The maximum input level signal to INx without damage is 3.8V (INx_max = VCCx + 0.5V = 3.3V + 0.5V).

Best,

Andrew

Isolation

Isolation forum

ISO6740-Q1: ISO6740QDWRQ1