DS1820 rod sensor

[ron_S]

i want to mzke a rod with 5 DS1820 int it
1- can i conect all yellow(signal) cables to the same pin
2- were can i get good quality
3- is there something i should know when soldering this or do i just connect each cable to the correct pin
yellow to signal black to gnd red to 3v3

 

[PaulS]

i want to mzke a rod with 5 DS1820 int it

You may want to select a DS18B20 since the DS1820 is obsolete.

1- can i conect all yellow(signal) cables to the same pin

Yes, see this tutorial.

2- were can i get good quality

From a reputable source in your country.

3- is there something i should know when soldering this or do i just connect each cable to the correct pin
yellow to signal black to gnd red to 3v3

The latter sounds good.

Paul

 

[el_supremo]

I believe you will also need a 4.7k pullup resistor from the signal pin to 3v3.
You can test your setup by running the Examples/OneWire/DS18x20_Temperature sketch. The code defaults to pin 10 but it is trivial to change this.
Here's output from running this code using a Teensy2.0 which has 6 DS18B20 on pin 16.

ROM = 28 60 D5 0 4 0 0 CF
  Chip = DS18B20
  Data = 1 80 1 0 0 1F FF 10 10 AE  CRC=AE
  Temperature = 24.00 Celsius, 75.20 Fahrenheit
ROM = 28 6E DD A4 5 0 0 EE
  Chip = DS18B20
  Data = 1 6D 1 59 46 7F FF 3 10 45  CRC=45
  Temperature = 22.81 Celsius, 73.06 Fahrenheit
ROM = 28 1E C2 0 4 0 0 69
  Chip = DS18B20
  Data = 1 71 1 0 0 7F FF F 10 AE  CRC=AE
  Temperature = 23.06 Celsius, 73.51 Fahrenheit
ROM = 28 E1 A3 0 4 0 0 E3
  Chip = DS18B20
  Data = 1 7F 1 4B 46 7F FF 1 10 33  CRC=33
  Temperature = 23.94 Celsius, 75.09 Fahrenheit
ROM = 28 25 AC 0 4 0 0 CF
  Chip = DS18B20
  Data = 1 75 1 4B 46 7F FF B 10 78  CRC=78
  Temperature = 23.31 Celsius, 73.96 Fahrenheit
ROM = 28 AF 42 A4 5 0 0 9E
  Chip = DS18B20
  Data = 1 73 1 4B 46 7F FF D 10 41  CRC=41
  Temperature = 23.19 Celsius, 73.74 Fahrenheit
No more addresses.

Pete

 

[MarkT]

Yes, a single 4k7 pullup at the far end ought to be enough, and 100nF decoupling capacitor on each sensor will help ensure reliable operation (the datasheet claims this isn't really necessary, I'm sceptical). Don't use parasite power mode, its very fragile in a long string of sensors like that - but you have 3 wires so you'll be OK.

The signal wires should be daisy-chained between the sensors, not all brought to one end of your rod, for good signal integrity.