Hi,
We have a broken controller because of ESD-air discharge on the 5-wire touchscreen.
Is the AM3354-ADC not protected against ESD?
The reference voltage is VDD_ADC (1.8V). Is a 1V8 TVS diode required or is a 3V3 TVS diode also helpful?
Many thanks
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Hi,
We have a broken controller because of ESD-air discharge on the 5-wire touchscreen.
Is the AM3354-ADC not protected against ESD?
The reference voltage is VDD_ADC (1.8V). Is a 1V8 TVS diode required or is a 3V3 TVS diode also helpful?
Many thanks
Hi
As you mentioned, the ESD protection must be provided externally. How can I protect the inputs against electrostatic discharges? In my design there are TVS diodes with a maximum breakdown voltage of 5.9 V. Are these TVS diodes suitable for the design? Do you recommend any circuits so that the input signal will not be affected?
Many thanks.
Yours sincerely
Christoph Capiaghi
Please check the parameter "Steady State Max. Voltage at all IO pins" in section 5.1 from the AM335X Datasheet Rev. G. Also check Note 8 below the table. Protection should ensure these voltages are not exceeded.
I personally have used ESD suppressors for high-speed lines (USB, HDMI, LVDS signals). These have very low capacitance and are the lowest voltage I could find.
Hi
Thank you for your support.
So I can use for example an external 5.3 V ESD diode to reduce the voltage stress? Does the internal diodes withstand the remaining voltage?
Many thanks.
Yours sincerely
Christoph Capiaghi
I would recommend searching for 3 - 3.6V ESD with very low capacitance in the pF range.
Hi
As you mentioned before, protection should ensure that the voltages in section 5.1 from the AM335X Datasheet are not exceeded. But when I use a 3 V - 3.6 V ESD diode, these voltage are exceeded. Does the internal diodes withstand the remaining voltage?
Yours sincerely
Christoph Capiaghi
The specifications in section 5.1 are the absolute maximum ratings. There is a Note 1 below the table:
"Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability."