The GDK101 is a solid state gamma radiation sensor module which has sensitive 10 PIN photodiodes and transimpedance amplifier circuit controlled by MCU. It is optimized for the low level gamma detection up to 200 µSv/h, for the measurement of our environmental condition with various IoT solutions. The uncertainty of sensing value is below ±10% by FTLAB’s precision technology using international standard calibrated procedure. It’s robustic design allow the long life time, more than 5 years without the need of maintenance. And the sensor module includes a internal MCU, it provide a smart analyzing function with built in a vibration sensor for recognition the error pulse caused by external mechanical shock. It also provides the I2C & UART interface for external microprocessor and Arduino. Also user can check the detecting waveform directly from the analog output port. It would be useful for verifying the energy spectrum analysis of gamma photons.