TXS0104 application

Nanfang Liao

Intellectual 2085 points

Hello

My customer's schematic is as below, VCCA is 1.8V and VCCB is 3.3V. There is a big overshoot voltage of pin A3, the time of overshoot is about 22ns, and the voltage is to 3V. What’s to result in this overshoot? Is there any risk of this overshoot voltage? I have suggested customer to put one small cap between pin A3 and GND and test the waveform again. thanks

Regards,

Nanfang

over 8 years ago

0 aozer over 8 years ago

TI__Mastermind 30765 points

Hello Nanfang,

Can you give us more information on your application? What devices are you interfacing with? What kind of interface are you using? What frequency are you operating at?

You mention that it happens on pin A3, are your other signals experiencing this overshoot?

0 Nanfang Liao over 8 years ago in reply to aozer

TI__Intellectual 2085 points

Hello,

1. The device is MDM9215(Qualcomm) .
2. The interface is PCM ;
3. 2048KHz
4. Yes，the phenomenon happens on all pins, but the A3 is most serious.

Regards,
Nanfang

0 aozer over 8 years ago in reply to Nanfang Liao

TI__Mastermind 30765 points

How long are your traces? It could be possible that you may need a small series resistor at the output for termination.

0 Nanfang Liao over 8 years ago in reply to aozer

TI__Intellectual 2085 points

Hello,

Customer has designed their board, so they can't put a series resistor at the output. Do you think there is risk?

Regards,
Nanfang

0 aozer over 8 years ago in reply to Nanfang Liao

TI__Mastermind 30765 points

Hi,

If the overshoot/undershoot voltages are within the recommended operating voltages found in the data sheet there should be no risk to damaging the device.

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TXS0104 application