DS2438 – TaaraLabs

1-Wire Temperature, Humidity and Light sensor uses one DS2438 1-Wire chip for three different measurements. This board is very similar to the 1-Wire Humidity and Temperature Sensor – even the board size is the same. The only difference is added BPW 35 S photodiode from Osram and the current sense resistor for light level measurements. The actual calibration (if needed) should be done in the software or by replacing the current sense resistor (default 4.7k 1%, before nov 2018 it was 240Ohm).

Features

1-Wire device: Maxim DS2438Z+ ADC with internal 13-bit temperature sensor
Humidity sensor: HIH-5030
Silicon PIN Photodiode: BPW 35 S
Supply voltage: 2,7-5,5V DC
Wiring on the full set model with the RJ12 plug (compatible with Maxim DS9490R USB to 1-Wire adapter):
1 – VCC 5V (yellow)
2 – NC
3 – OW 1-Wire data (green or blue)
4 – GND (red)
5 – NC
6 – NC (black or none)

Resources

Buy

Bare PCB: 3€

Pre-assembled: 52€

Full set: 57€

NB! The price of main parts has increased significantly due to the chip shortage. Our prices are adjusted accordingly.

: Schematic

: Board layout

: Pre-assembled

: PCB

: Full-set

1-Wire Humidity and Temperature sensor is a low-cost Open Source device for measuring temperature and relative air humidity in 1-Wire micro LAN network. 1-Wire network allows multiple devices connected on the same bus in parallel. Every 1-Wire device has a unique 64bit ID.

Features

1-Wire device: Maxim DS2438Z+ ADC with internal 13-bit temperature sensor
Humidity sensor: HIH-5030 or HIH-5031 (condensation-resistant)
Supply voltage: 2,7-5,5V DC
Conformal coating option adds some additional protection against moist air
Wiring on the full set model with the RJ12 plug (compatible with Maxim DS9490R USB to 1-Wire adapter):
1 – VCC (yellow)
2 – NC
3 – OW 1-Wire data (green or blue)
4 – GND (red)
5 – NC
6 – NC (black or none)