TDC7200: INTB delay

ohad kowalski

Prodigy 90 points

Part Number: TDC7200

Hi,

BLUE - start pulse

GREEN - stop pulse

purple - INTB

the Interrupt Mask Register (0x03) is set to 0x01 ( only - New Measurement Interrupt enabled).

can someone explane me why i have a delay between the stop pulse and the INTB ? (~1us)

tnx

ohad

over 6 years ago

0 Bharat Aravamudhan over 6 years ago

TI__Genius 11015 points

Ohad,

I will check on this and respond within a couple of days.

0 ohad kowalski over 6 years ago in reply to Bharat Aravamudhan

Prodigy 90 points

Hi Bharat ,

thanks.

im looking farward for your reply.

ohad

0 Bharat Aravamudhan over 6 years ago in reply to ohad kowalski

TI__Genius 11015 points

Ohad,

This time is taken by the internal processing by the device post the last STOP signal to toggle the INTB to low, we do not have exact time it takes between the last STOP & INTB toggle. Please refer to the figure 19 of datasheet even in muti-cycling mode there is a certain time post the last STOP signal for the device to toggle the INTB pin to low.

0 ohad kowalski over 6 years ago in reply to Bharat Aravamudhan

Prodigy 90 points

Bharat,

1st thanks for the reply.

i saw figure 19 but the is no time scale there.

2nd i think this kind of data have to be in the datasheet.

because if you want to work in a fast mesurment cycle for example (start pulse every 2us)

and get your stop pulse after <500ns (mode1) , there is a dead time (of aprox. 800ns to 1us) that you are waiting for INTB to be toggle.

and thats before you are starting your SPI interface.

again thanks for the help!

ohad

0 Vaibhav Garg10 over 6 years ago in reply to ohad kowalski

TI__Intellectual 1020 points

Hi Ohad,

Thank you for explaining why this data is useful to have. Unfortunately that data is not available for this device to put in the data sheet. You might have to measure this time on a few devices in your setup and add some guard band to account for it in the software.

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TDC7200: INTB delay