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TheAustrian / Wemos-D1-Mini-BME280-Weather-Station

Simple Weather Station Code using an ESP8266 and a BME280 sensor. Data is handled via PHP and stored in a MySQL database
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Need for Step Up Converter #6

Open Ph0non opened 6 years ago

Ph0non commented 6 years ago

I build something familiar with the same battery charger. But the TP4056 only provides the battery voltage. E. g. with 4.2V (fully loaded battery) and VCC connected to 5V Vin I can't read out the DHT22 in my build, so i connected a MT3608 DC-DC Step Up Converter to boost the input voltage from battery (OUT+/- from TP4056) to fixed 5V. Battery sensing should left connected to TP4056.

Any other Step Up Converter should also do (there is no high load in current, around 80mA in my build with DHT22, BMP280 and 0,96" OLED)

DIYglenn commented 6 years ago

Won’t this issue be fixed by running the DHT22 from 3.3V rarher than the 5V rail?

The Wemos has a regulator allowing for the correct 3.3V when connecting power to USB or 5V, but the 5V rail will follow the battery voltage.

Samgarr commented 6 years ago

Same problem here. As quick fix i connected 3.7V (from 18650 cell) output to the 3.3V Vin of Wemos board. There is 3 ~ 3.6V tolerance for input votage, so 3.7V wont hurt it so much.

KDMcMullan commented 2 years ago

Same problem here. As quick fix i connected 3.7V (from 18650 cell) output to the 3.3V Vin of Wemos board. There is 3 ~ 3.6V tolerance for input votage, so 3.7V wont hurt it so much.

4.2V from a fully charged battery will fry your Wemos.