Tool/software:
Hi TI Team,
We have some questions regarding SN54SC2T74MPWTSEP.
Could you help me for the following questions? -
1. Are there any IBIS models and LT Spice models available? If so, could you share them with me?
2. Current implementation involves "D" and "CLK" pins Grounded and we are controlling CLRn and PREn as inputs. In this scenario, do we expect to have some series resistors at "Q" output?
Scenario 1 - We have noticed that without the series resistor at the "Q" Output, this part seems to get destroyed(even visually), and "Q" output no longer latches. During this test, we were injecting 1kHz (50% duty) signal to "PREn" input pin. The frequency we injected seem to be well within the Fmax range listed in the datasheet.
Scenario 2 - We ran the test again with a 50-Ohm series termination resistor at "Q" output, and noticed there are current pulses of ~12mA that is less than 100us every time Q latches on and off. The part survives during this test and no longer gets damaged with this 50-Ohm termination resistor.
We believe that without the terminating resistor, the current spike has to be much bigger and exceeds the output current rating of the Q output and the part is getting damaged.
Is this pulse spike typical and expected? Would this be related to the capacitance of the Q output node? due to maybe having a long path of trace? If you could share your thought, that would be great.
The datasheet states that "Absolute Maximum Rating" of continuous output current is 25mA. Would it be the same for short duration current pulses?
With VCC being 5V, would you recommend adding a series termination resistor to limit the output current < 15mA as stated in the datasheet? Otherwise, what resistance value would you recommend?
Thank you
