2 SENSORS data log

Hi I am newbie here

I have a project which I am not sure which components and board I should use
basically need a temp & Humidity sensors to log the data in a chip as wearable device, then load the data from the chip thru USB

the challenge is that I need it be as small as possible with the longest power supply applicable

Any recommendation?

Sam

So you probably need a DHT11 sensor with an Arduino Nano.

with the longest power supply applicable

Not sure if you mean the smallest power supply, eg battery which will depend on how long you want it to run before a recharge , or very long wires ??

How much data do you want to store?

Ie how often do you want to sample ? For how long?

if this tots up to < 2kB the on-chip eeprom would do . If not an SD shield would be necessary..

regards

Allan

Problem with the idea of a wearable sensor is that the human body will significantly affect the temp and humidity reading, making it useless for measuring the surroundings.

If you can figure out a way around that problem, I would not recommend dht11. Very poor accuracy. How about an sht21?

Sht21 has an i2c interface, and you can get i2c eeprom chips if the Arduino does not have enough. I2c eeprom should be much more compact and low power than SD.