AN4038 datasheet(37/39 Pages) STMICROELECTRONICS

No de pièce	AN4038

Description	Guidelines to optimize proximity detection with STM8TL5xxx capacitive sensors

PDF	39 Pages

Scroll/Zoom	100%

Fabricant	STMICROELECTRONICS [STMicroelectronics]

Site Internet	http://www.st.com

Logo

37 / 39 page

AN4038

Conclusion

Doc ID 022686 Rev 1

37/39

7.2

Influential parameters summary

Table 9 summarizes the main parameters influencing detection distance and noise.

In conclusion, many considerations need to be take into account including application

constraints, environmental change, board design constraints, and power supply.

Generally, the best thing to do is to develop a prototyping proximity board to fine-tune the

different parameters of the application and come to a reliable solution in terms of sensitivity

and stability.

Table 9.

influential parameters summary

Parameter

Detection

distance

Noise

Minimum interval

recommended

Increasing CS capacitor

Increasing target reference

+++

≥300

Decreasing detection threshold

≥4 ∗ noise standard deviation

Spacing between Tx and Rx

electrode

+++

≥2 mm

Increasing Tx/Rx length

Increasing Tx/Rx width

≥1.5 mm

Decreasing distance between ground

plane and sensor

---

Decreasing distance between ground

surrounding and sensor

---

≥2 mm(with air as dielectric)

AN4038 Fiches technique(PDF) 37 Page - STMicroelectronics