AN4451

Conclusion

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5

Conclusion

UV sensors provide an extremely small current depending of the level of UV radiation. To

convert this current to an adequate voltage, a transimpedance amplifier is used. Then, an

ADC can convert the signal into the digital domain. For this kind of application, it is

important to choose a CMOS rail-to-rail amplifier with a low Vio to avoid inducing big errors

on the output. The OA1MPA is a good option for such a UV sensor application. However,

stability must be also taken into account and the right components must be chosen,

particularly the feedback capacitor Cf which helps to stabilize the system, limit bandwidth,

and reduce noise.

Benefit from a wide portfolio of analog switches, voltage references, temperature sensors,

pressure

sensors,

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microcontrollers

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application,

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STMicroelectronics your one-stop shop as illustrated in Figure 10.

Figure 10: UV sensor evaluation board