RD3204 Nuclear sensor

Hi every body ,
I have a problem about nuclear detection radiation . my sensor is RD3024 and the output is pulse . I use ext interrupt of microcontroller to read pulse from sensor . My board include Sim908 module more . When sim908 module dont powrt up, all things are ok . But if i power module sim908 then pulse continuos at output pin althrought input sensor is nothing . What the matter here ? Everyone can help me ?
Thanks !

Post exact hardware circuit. Can your sensor pick up noise and provide pulse output ? I mean is it too sensitive ?

haohaodk46 said:

Hi every body ,
I have a problem about nuclear detection radiation . my sensor is RD3024 and the output is pulse . I use ext interrupt of microcontroller to read pulse from sensor . My board include Sim908 module more . When sim908 module dont powrt up, all things are ok . But if i power module sim908 then pulse continuos at output pin althrought input sensor is nothing . What the matter here ? Everyone can help me ?
Thanks !

Click to expand...

Nice detector.... Bad layout/integration... Make sure you have a decoupling cap near the NOR gate and short twisted pair wires from switch and to sensor. (/gnd )

Distance between Sensor and pulse stretcher must be short or shield and choked with ferrite bead to preserve integrity of 10us pulse and no GHz RFI getting rectified in your circuit signals. Sensor is robust.

I had add a lowpass filter front of sensor's vdd pins and solved pulse noise when power up SIM908 module . But I still encounter this bug when I call to the Sim908 module . I add a capacitor 220uF front of vdd pin of sensor but still not change . Any the way that resolution this matter ?
This is datasheet of sensor : https://www.teviso.com/file/pdf/RD3024_DataSpecification.pdf
Please can you help me !

SunnySkyguy said:

Nice detector.... Bad layout/integration... Make sure you have a decoupling cap near the NOR gate and short twisted pair wires from switch and to sensor. (/gnd )

Distance between Sensor and pulse stretcher must be short or shield and choked with ferrite bead to preserve integrity of 10us pulse and no GHz RFI getting rectified in your circuit signals. Sensor is robust.

Click to expand...

Thanks for providing the datasheet. You have been asked however to show a schematic of your circuit. We can just guess that the power supply noise requirement isn't achieved in your circuit.

GSM modules are consuming pulsed current when transmitting, effcient supply filtering is mandatory. RF succeptibility of the sensor might be an additional problem. Because the sensor current consumption is rather low (400 µA) , it would be an appropriate means to supply in through a RC filter. Make sure that 3V supply isn't undershot.

I have been used external battery only supply for sensor but when the module receive incoming call still cause out pulse of sensor increase continuous .So noise power not here . Can the noise electrical field effect to sensor's output wire ? And to decrease this noise , must I do things ?
Thanks !