TXV0108-Q1: From 3.3V Port A to 1.2V Port B Maximum data rate

The typical propagation delay of 2.5 ns would correspond to an estimate of 400 Mbps. A safety factor of 100 % might be OK. (But 1.2 V is the lowest supported supply voltage, and there is a reason that TI is not willing to guarantee any timing at this voltage.)

There is no faster translator. But the fastest logic family at 1.2 V family is AUC (200 Mhz), which has overvoltage-tolerant inputs, so you could use a buffer like the SN74AUC34 or SN74AUC244. (There is no automotive-qualified AUC device.)

Hi Clemens,

Thank you for your feedback. However, I think our concern for the translator data rate is the toggling speed instead of the propagation delay. I am wondering if you have test data to share how fast can be guaranteed with TXV0108-Q1 when translating from 3.3V to 1.2V;

For the two parts you recommended, they don't have the speed information at 1.2V as well, so can they be guaranteed for 100MHz at 1.2V?

Hello George,

I can run this test (TXV 3.3V -> 1.2V) in the lab and report back.

Regards,

Josh

Hi Josh,

Appreciate this.

Regards,

George

Hello George,

I wasn't able to complete lab measurements on Friday. Will prioritize this first thing Monday. Thanks

Regards,

Josh

Thanks Josh.

Thank you so much Josh. Just wondering if above testing is with any current loaded? If not would it possible to test with 4mA or 2mA output current loaded on the 1.2V side?

Regards,

George

Hello George,

The above testing does not include any current load. I can recapture the waveforms with ~2mA load.

Regards,

Josh

Thanks again Josh. If same difficulty to apply the load current, can you capture the waveform with 4mA load, because that should be situation we have on the board.

Hi George,

Please allow us some time to capture this data for you.

Regards,
Jack

Thank you so much Josh.

Was this testing done at B1 or B8? Our customer's concern is if the device can drive all ouputs at the same time (B1-B6 in our case). I am wondering if I can request the test result based on loading B1 to B6 outputs together with (15pF or more load , 4mA each). Not only one output. 

Regards,

George

Hello George,

The test above used A8 -> B8. On the TXV0108-EVM, IOs #1 and #8 have the shortest trace length.

We don't have the equipment to run all 6 outputs at the same time unfortunately. The signal generator we use only has two outputs.

Regards,

Josh

Hi Josh,

Understood. If only two outputs from generator, is that possible to input A1/A2/A3 with one generator, A4/A5/A6 with the second generator, or A1~A6 with the same generator? In that way 6 gates maybe able to be loaded together?

Regards,

George

Hello George,

I would need to check if there is a way to fanout the signal from the signal generator. This signal generator is the only one with great signal integrity at 100MHz. 

Regards,

Josh