SN74HCT273: About the test conditions of tpd

Luna

Intellectual 830 points

Part Number: SN74HCT273
Other Parts Discussed in Thread: SN74HC273,

Hi, team.

The test conditions of tpd are written "from /CLR to Any". Is this correct?

I think "from CLK to Any".

Best Regards,

over 4 years ago

0 Clemens Ladisch over 4 years ago

Guru 243980 points

The CLR input can affect the outputs, so it is correct to specify t_pd for this pin.

There are other datasheets that do specify t_pd for both CLK and CLR (e.g. SN74HC273). Apparently, that line is missing for the SN74HCT273.

0 Luna over 4 years ago in reply to Clemens Ladisch

Intellectual 830 points

Dear Clemens Ladisch

Thank you for your reply.

I understand that the test conditions of tpd are correct "from /CLR to Any".

However, I thought that it would be "from CLK to Any" because the measurement conditions of tpd and tPHL were the same but the specifications were different.

Another reason is that the delay from the rising edge of CLK is usually faster than that of /CLR.

Best regards,

0 Clemens Ladisch over 4 years ago in reply to Luna

Guru 243980 points

As far as I can see, the CLK specification is simply missing.

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SN74HCT273: About the test conditions of tpd