SN74AVC4T774: Please review the schematic

Dear Dylan,

Thank you for your support. Actually my customer have a problem with sleep current when \OE is high.

I think that the device goes to sleep when \OE is high, and my customer measured the current consumption of SN74AVC4T774 with power supply (only connected SN74AVC4T774 and nothing else) the current was 2~3mA. is it normal operation? I need your confirmation about it.

and if it is true, can you recommend similar IC which current consumption is extremely low? cause my customer uses a battery for the power, they need very low power consumption.

Best regards,

Chase

Dear Clemens,

Thank you for your support.

You mean that pullup resistors on A/B inputs and outputs are helpful for reducing sleep current? Cause I did not see about it in the datasheet or any other documents.

Please check this issue. Thanks.

Best regards,

Chase

This is footnote (3) in section 7.3.

Dear Clemens,

I understand that all unused pins should be connected to GND or Vcc. and there are no inputs and outputs that are unused.

And my customer tested about pullup resistors on A/B side with 1K/10K resistors, it did not work at all for current consumption.

Could you advice more about it? or it would be good if you suggest another IC which sleep current is extremely low.

Best regards,

Chase

If the pull-up resistors do not help, then the problem is not caused by floating inputs.

How exactly was that current measured? Can you confirm that that current is flowing into V_CCA/B and out of GND?

Dear Clemens,

They measured current consumption using power sup[ply, only connected it to SN74AVC4T774.

current consumption when \OE is high is about 2~3mA. is it right value?

Best regards,

Chase

Dear Dylan,

Thank you for your support. I requested what you mentioned to my customer.

Here is a question, what do you expect about sleep current when \OE pin is high?

Best regards,

Chase

Hi Chase,

I expect it to be within the specs I mentioned before.

Dear Dylan,

Thank you for your support.

my customer tested multiple PCB and swap ICs. they found that sleep current is very low with new IC.

I think that previous chip electrically damaged somewhere.

Anyway Thank you for your support again.

Best regards,

Chase

Hi Clemens,

What's the max pull up/down resistor could be applied to the input, to make the output stable? My customer is asking this question, since they want lower current consumption. Thanks!

BR,

Zach

The voltage drop caused by the leakage current must not become too large. So if you want no more than 0.5 V at a 5 µA input, the largest resistor is 0.5 V / 5 µA = 100 kΩ.

So the leakage current is always around 5µA, no matter how large pull-up resistor is? Thanks.