PCA9534: Minimum VOH for 3.3V voltage.

deepak naiknavare

Part Number: PCA9534

I am doing worst case calculation with PCA9534 minimum high level O/P voltage (@10mA, Vcc=3.3Vsupply) .

As per the datasheet section 7.5, i plotted different voltage levels vs Vcc and approximated a minimum VOH of 2.8V (for 3.3V supply i.e Vcc-VOH=0.5V) .

But looking at the figure 7-17, even for the complete temperature range the difference (Vcc- VOH) < 200mV for ~3.3V.

What shall i consider as the worst case VOH for 3V3 supply with 10mA load?

over 1 year ago

0 Clemens Ladisch over 1 year ago

Guru 259890 points

Section 7.8 shows typical values.

Section 7.5 specifies guaranteed worst-case values.

0 deepak naiknavare over 1 year ago in reply to Clemens Ladisch

Prodigy 140 points

Thanks for the reply. I will consider the values in section 7.5.

Just to have more clarity - Why fig 7-17 does not have worst case values considering it is graph over complete temperature range?

0 BOBBY over 1 year ago in reply to deepak naiknavare

TI__Guru 53590 points

Section 7.5 shows what we guarantee in the datasheet, by practice there is some margin on these values. Figure 7-17 shows about a 100mV difference for ~5Vcc between Vcc and VoH while section 7.5V basically says we guarantee The most difference you will see is 750mV at 4.75Vcc drawing 10mA. So if the true value reported in validation testing is 100mV (from figure 7-17) then the margin for error is about 650mV. It's basically allows TI to have buffer room since this is a written guarantee to the buyer.

-Bobby

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PCA9534: Minimum VOH for 3.3V voltage.