TLK1211: TRANSMITTER/RECEIVER CHARACTERISTICS

Taemin Ahn

Part Number: TLK1211

Hi team

1. According to the top above specification, TXP-TXN is 600 ~ 1100mV.
Is this the value that makes High? Or is it the range of TXD?

In the figure second above, the value of VOD is between -1V and 1V.
0V is also 0 in absolute value. How is the range of 600 ~ 1100mV calculated?

2. In the figure above, the voltage values of TXP and TXN are not specified.

Transmit common mode voltage range is 1000 ~ 1400mV.
TXP = 1000 ~ 1400mV, TXN = 1000 ~ 1400mV Is this correct?

Thanks

over 5 years ago

0 Malik Barton57 over 5 years ago

TI__Guru 64326 points

TM,

1. This refers to the peak to peak voltage of VOD which is equal to |TXD -TXN|. TXN is a inverted version of TXD. Does this answer your question?

2. This is correct.

0 Taemin Ahn over 5 years ago in reply to Malik Barton57

Intellectual 795 points

0 Malik Barton57 over 5 years ago in reply to Taemin Ahn

TI__Guru 64326 points

TM,

TxD = TX+
Vcm is the common mode of the differential signals. VOD is the output differential peak to peak voltage. Another way to think about this is that Vcm is the DC offset of Tx+ and Tx-. Tx+ and Tx- also have a AC swing. Using the Vcm voltage to calculate VOD is incorrect.

0 Taemin Ahn over 5 years ago in reply to Malik Barton57

Intellectual 795 points

0 Malik Barton57 over 5 years ago in reply to Taemin Ahn

TI__Guru 64326 points

TM,

VID is referring to peak to peak voltage.The high low values change with the input common mode voltage. VOH = Vcm + VID/2 and VOL = Vcm-VID/2, so if your input common mode is 2 V then your high level is 2.4 V and your low level is 1.6 V. The timing aspect of the receiver should also be considered.

0 Malik Barton57 over 5 years ago in reply to Malik Barton57

TI__Guru 64326 points

TM,

Is any more support needed for this issue? If so please reply with any relevant details so that I can further assist you. For now I will be marking this thread as "TI Thinks Resolved".

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TLK1211: TRANSMITTER/RECEIVER CHARACTERISTICS