7805 as a Temperature Sensor ! - Page 1
Forum section: electronics / projects

author: Kedar264
author_rank: Regular Contributor
timestamp: June 17, 2015, 04:59:56 pm
content: 78l05 Positive 5 volts regulator can provide 100 ma max , if you overload it with excessive load then ,inbuilt over load (thermal overload protection ) kicks in and lowers the current flowing through itThis lower side of 7805 can be used as temperature sensor. You can make temperature sensor from voltage regulator and use for your Arduino,Raspberry pie ,pic projects.Watch this videohttps://youtu.be/OuMZRigoAhA

author: suicidaleggroll
author_rank: Super Contributor
timestamp: June 17, 2015, 05:17:15 pm
content: How much power does that waste and how long will the 7805 last running at its thermal limit 24/7? How reliable and repeatable is the measurement? What is the advantage over using a simple thermistor voltage divider? Just because something can be done, doesn't mean it should be done.

author: IanB
author_rank: Super Contributor
timestamp: June 17, 2015, 05:37:51 pm
content: Quote from: Kedar264 on June 17, 2015, 04:59:56 pmOn the list of "dumb ideas that should never have seen the light of day", that has to rank right up near the top...

author: lincoln
author_rank: Regular Contributor
timestamp: June 17, 2015, 05:50:55 pm
content: You could also use lm34, lm35, or a diode wired transistor or really any other ideas would be better.

author: Kalvin
author_rank: Super Contributor
timestamp: June 17, 2015, 05:55:02 pm
content: Nice find. However, it would be a bit of a challenge to measure the temperature of an ice cube, for example.

author: Yansi
author_rank: Super Contributor
timestamp: June 17, 2015, 05:57:40 pm
content: Clear demonstration of what means to be an "arduino, raspi, ..." hobbyist in the 21th century. Instead of using technology to st. useful, only inventing idiotic things with neither use nor common sense.Please throw this topic into the bin.

author: senso
author_rank: Frequent Contributor
timestamp: June 17, 2015, 06:20:10 pm
content: Quote from: Yansi on June 17, 2015, 05:57:40 pmBut moooooooom its an hack!

author: wraper
author_rank: Unknown
timestamp: June 17, 2015, 06:23:44 pm
content: Are temperature sensors supposed to heat the environment they are measuring?As of current limiting, it occurs when the die temperature reaches at least 140oC or even more. I would be surprised if the IC would survive more than a year of continuous operation, likely less.

author: Kedar264
author_rank: Regular Contributor
timestamp: June 17, 2015, 06:34:00 pm
content: Ok, i showed you one alternative way , it's not the most effective one but in very custom applicationsLike world's most inefficient temperature sensor, which change temperature of measurand before measurement and never reach to its steady state value .......Sorry, but I think Its cool and i shared this.

author: wraper
author_rank: Unknown
timestamp: June 17, 2015, 06:36:31 pm
content: Quote from: Kedar264 on June 17, 2015, 06:34:00 pmJackass is cool too

author: suicidaleggroll
author_rank: Super Contributor
timestamp: June 17, 2015, 06:40:17 pm
content: Quote from: Kedar264 on June 17, 2015, 06:34:00 pmIt would still be a terrible idea, no matter how "custom" the application is.This is a measuring device that changes what it's measuring and self-destructs after a short amount of time. What possible use could that have? Planned obsolescence in a hot-wire anemometer with terrible accuracy and latency?

author: electr_peter
author_rank: Unknown
timestamp: June 17, 2015, 06:44:37 pm
content: Thanks for the idea, but I can judge temperature by feel/look/smell much better, with more accuracy, response time and range than that. In other words, video shows useless temperature sensor.

author: eneuro
author_rank: Super Contributor
timestamp: June 17, 2015, 06:56:57 pm
content: Quote from: electr_peter on June 17, 2015, 06:44:37 pmNope, video doesn't show any temperature sensor only small heaterHopefully, only 12 hits so far or so-unless it will be linked somewhere on "beduino" (I meant arduino) forum, very little chance to be the temperature sensor of choice for XXIst century new age of "module" toys programmed by "experienced" "beduino" folks in high level anguages like... basic, logo, etc