TLV809E: Reset exception

Part Number: TLV809E


Hi Support Team,

We are currently utilizing the TLV809EC26DBZR in our circuit design and have encountered an issue where the Reset pin frequently fails to output a High signal. In our configuration, the Reset pin is connected to a CPLD input and includes a 0.1uF capacitor to GND.

To diagnose the issue, we conducted the following experiments:

  1. Removed the TLV809E and added a 100k pull-up resistor: The High signal was output correctly, confirming the CPLD input is functional.

  2. Connected the TLV809E VDD pin directly to the 3V3 rail: The Reset pin functioned normally (High).

  3. Reduced the resistance values of the original voltage divider: The Reset pin functioned normally (High).

  4. Removed the 0.1uF capacitor from the Reset pin: The Reset pin functioned normally (High).

Based on these results, we suspect that the charging current of the Reset capacitor causes a voltage drop. When VDD is supplied via a high-impedance resistor divider, the voltage may momentarily dip below the threshold, causing the device to reassert Reset.

Could you please clarify whether the TLV809EC26DBZR supports divider-fed VDD, or if it is strictly intended to be supplied by a low-impedance power rail?

We look forward to your professional feedback. Thank you.




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