Joe Desbonnet writes, “This looks like an interesting lightning sensor the AS3935 by Franklin. Available at Digi-Key for about $8 in single quantities. Unfortunately the eval kit is $300.”
According to the manufacturer, “The AS3935 detects lightning activity as it approaches from up to 40km away which provides a much longer distance for lightning warning. In addition, the AS3935 identifies and rejects interference signals from common man-made sources such as: fluorescent lighting, motors, microwave oven, switches, etc.” Features include programmable detection levels allow setting of the threshold setting for optimal configurability, SPI and I2C interface for control and register reading, automatic antenna tuning, supply voltage range from 2.4 to 5.5V and temperature range -40°C to 85°C.
Via the contact form.
Now this would be cool to add to the work being done on the Weather Radio Shield !! Check the forums.