Post by thread:Need source for light sensor.

>Hi I'm doing a project where I measure the amount of light in the room >with a PIC16c71. Does anyone know of a sensor that can measure light >intensity? Thanks. How about just using a photocell? It's resistance varies (inverse) with the amount of light. You could put it in the feedback loop of an opAmp, and probably linearize it somewhat before sending the voltage to the PIC. In addition, Burr Brown makes a series of photodiodes with built in amplifiers. Chris ---------------------------------------------------------------------------- |Check out my WWW page at http://www.access.digex.net/~cps/ for ham radio | |software for the Mac; Free Radio, Shortwave Radio, and Spy Numbers Stations | |information. | |Finger me (spam_OUTcpsTakeThisOuTaccess.digex.net) for my PGP Public Key | ---------------------------------------------------------------------------- "Those who would gladly sacrifice liberty for security deserve neither." -Ben Franklin

msg: >Hi I'm doing a project where I measure the amount of light in the room >with a PIC16c71. Does anyone know of a sensor that can measure light >intensity? Thanks. How about just using a photocell? It's resistance varies (inverse) with the amount of light. You could put it in the feedback loop of an opAmp, and probably linearize it somewhat before sending the voltage to the PIC. In addition, Burr Brown makes a series of photodiodes with built in amplifiers. Chris ---------------------------------------------------------------------------- |Check out my WWW page at http://www.access.digex.net/~cps/ for ham radio | |software for the Mac; Free Radio, Shortwave Radio, and Spy Numbers Stations | |information. | |Finger me (.....cpsKILLspam@spam@access.digex.net) for my PGP Public Key | ---------------------------------------------------------------------------- "Those who would gladly sacrifice liberty for security deserve neither." -Ben Franklin

>Hi I'm doing a project where I measure the amount of light in the room >with a PIC16c71. Does anyone know of a sensor that can measure light >intensity? Thanks. > Take a TSL230 form TI for example. Good look. Claus =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D Dr. Claus K=FChnel Tel/Fax +41 1 785 02= 75 Consulting & Distribution E-Mail kuehnelKILLspamdial.eunet.ch =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D

>I considered using a phtocell but was hoping to find a specialized IC >that produced linear output. The best would be one with a serial interface. Texas Instruments: TSL220 Light to frequency converter TSL230 Programmable light to frequency converter Regards, ------------------------------------------------------------------------------- Ronny H. Kavli Without love, money and computers .....kavliKILLspam.....ludd.luth.se it would almost be easy to live...

Try the Digi-Key catalog, Nuts & Volts magazine, or surplus stores. I would suggest using an 'LDR'-Light Dependent Resistor. These are often used for sensing ambient light to control indicator panel brightness. Their resistance decreases with increase in light. A 'photocell' produces a small signal that really needs a buffer amp to make the signal usable. The LDR is more simply used in series with another selected resistor (Rx) as a voltage divider. Connect the LDR to +5v, Rx to GND. The voltage at LDR/Rx tiepoint can be fed to PIC A/D INPUT or other device. Rx should be selected to 'scale' the signal into the desired operating voltage range for your needs. You might also try a cool-white dome to integrate the ambient light so that the sensor does not get saturated by infrared heat sources.

> Hi I'm doing a project where I measure the amount of light in the room > with a PIC16c71. Does anyone know of a sensor that can measure light > intensity? Thanks. I too have a need to measure the amount of light. I would appreciate if you would pass on any information you might obtain. TIA, Richard Rosenheim EraseMErrosespam_OUTTakeThisOuTaccessnv.com

> I considered using a phtocell but was hoping to find a specialized IC > that produced linear output. The best would be one with a serial interface. My preference too. Richard Rosenheim rrosespam_OUTaccessnv.com

> > Hi I'm doing a project where I measure the amount of light in the room > with a PIC16c71. Does anyone know of a sensor that can measure light > intensity? Thanks. > > Burr-Brown has an IC with voltage level outputs, OPT101. -- ----------------------------------------------------------------------- Micheal Yano, CIMTEK Automation Systems | @spam@miyKILLspamcimtek.on.ca, KILLspami1320285KILLspamibmmail.com | PROFS: IBMMAIL (I1320285) |

>Hi I'm doing a project where I measure the amount of light in the room >with a PIC16c71. Does anyone know of a sensor that can measure light >intensity? Thanks. --------------------------------------------------- A Texas Inst. TSL230B Light to Voltage Converter. Dean Dean Hadley Lawrence Livermore Natl. Lab Livermore, Ca USA RemoveMEhadley1TakeThisOuTllnl.gov

> >>Hi I'm doing a project where I measure the amount of light in the room >>with a PIC16c71. Does anyone know of a sensor that can measure light >>intensity? Thanks. > >--------------------------------------------------- >A Texas Inst. TSL230B, Light to Frequency Converter. >I had a free sample sent to me from TI. > >Dean > > >Dean Hadley >Lawrence Livermore Natl. Lab >Livermore, Ca USA >spamBeGonehadley1spamBeGonellnl.gov Dean Hadley Lawrence Livermore Natl. Lab Livermore, Ca USA TakeThisOuThadley1EraseMEspam_OUTllnl.gov