TLIN1027-Q1: TXD & RXD Pin Clamping Diode

PY (Pengyu) Song

Part Number: TLIN1027-Q1

Hi team,

Could you please advise if there is/are any clamping diode(s) at TXD and RXD pins? It will be good if there is a simplified drawing on the pin model. Thank you!

over 1 year ago

0 Danny Bacic over 1 year ago

TI__Mastermind 22485 points

Hi PY,

I assume you are asking about whether there is backbiasing from TXD to VSUP when unpowered, or if V_SUP < V_LOGIC? You can apply between -0.3 V and 6 V to the TXD pin without concern for damaging the part, even when unpowered, though it is recommended to keep this voltage between GND and 5.25 V. This also applies to the RXD pull-up.

If negative voltages are applies, then yes, I would expect to see current flow from GND to the pin.

Does this help clarify? Or is there a specific use case I can help address?

Best,

Danny

0 PY (Pengyu) Song over 1 year ago in reply to Danny Bacic

TI__Expert 5860 points

Hi Danny,

Thank you. This is for customer to understand the device pin model for them to implement test in their factory - open, short, leakage tests etc. Customer will need to know if there is/are clamping diodes associated with the pins in order to implement respective tests.

It is not so much about the max voltage rating.

+1 Danny Bacic over 1 year ago in reply to PY (Pengyu) Song

TI__Mastermind 22485 points

PY,

Ok, thanks for the clarification!

Yes, there is a diode from GND to TXD/RXD on the TLIN102x(A)-Q1 devices. Usually, when doing a diode check from GND to TXD/RXD on a multimeter, I see a forward voltage just over 0.5 V.

Hopefully this helps, let me know.

Best,

Danny

0 PY (Pengyu) Song over 1 year ago in reply to Danny Bacic

TI__Expert 5860 points

Hi Danny,

Any clamping diode pointing upwards? Like from pin to Vsup?

+1 Danny Bacic over 1 year ago in reply to PY (Pengyu) Song

TI__Mastermind 22485 points

Hey PY,

Between TXD/RXD and VSUP, it should be high impedance, provided the pins are kept within the absolute maximum ratings.

Best,

Danny

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TLIN1027-Q1: TXD & RXD Pin Clamping Diode