DS18B20 Temp. Sensor + atmega168 ?

Development Boards MicroMod
1

Greetings,

I have set up a 5V power supply which is powered by a 9VDC 650mA wallwart.

I have a green led plugged in which lights up when the power switch is on.

I have connected the DS18B20 as follows:

pin 1 - GND

pin 2 - PD6 (pin 12 of the atmega168)

pin 3 - 5V rail

I have also connected a 4.7k resistor between pin 2 and 3.

When I flip the power switch on, the green led turns on and slowly dims out.

When i unplug the DS18B20, the led stays on.

Is the DS18B20 using too much power?

Best regards,

Chris

2

Something is wrong with either your wiring or the wall wart. The 18B20 uses a just a miniscule fraction of the amperage that should be available from your wall wart. Do you have a handheld meter? It would go a long way in troubleshooting the problem, I think.

Otherwise, posting a schematic would help myself and others better understand what you’re describing.

3

I looked into my circuitry after reading your response.

Turns out there was a short.

Thanks ! :slight_smile:

4

cjoudrey:
I looked into my circuitry after reading your response.

Turns out there was a short.

Thanks ! :slight_smile:

**Doh!.**