Regarding "CYBT-413034-EVAL EZ-BT™ Module Arduino Evaluation Board"

[AmHa_650526]

If I open the evaluation board schematics present in "https://www.cypress.com/documentation/development-kitsboards/cybt-413034-eval-ez-bt-module-arduino-e...", the value of R1 and C10 is 100K and 0.22 uF.

I had a doubt that as per CYBT-413034-02 datasheet, it is required that

"During power on operation, the XRES connection to the CYBT-4130xx-02 is required to be held low 50 ms after the VDD power supply input to the module is stable".

My question to you is how 100K and 0.22 uF meet this requirement, since the value of tau = 100K x 0.22 u = 22 ms, and VIH is 2.4V (for VDD = 3 V)

In the evaluation board, VDD is 3.3 V and time taken to reach 2.4 V is 28 msec (It was derived by substituting VS = 3.3 V and VC = 2.4 V, in the above equation).

Please clarify.

Thanks in advance for responding.

[SheetalJ · Accepted solution]

Hi AmHa_650526​,

The reset time is less than recommended - 50ms (B0) or 35ms (B1).

Do you encounter issue with the EVAL? There is a press button SW1. It can be pressed if the board fails to boot.

[AmHa_650526]

No, I am not facing any issue. Just like that, I had got that doubt and I asked. The CYBT-413034-EVAL works fine (i.e., it boots properly without pressing SW1 also).

[SheetalJ]

Thats great.!