Need help on Infrared LEC......

Status
Not open for further replies.
U

umliu37

New Member
hi guys, i need some help with my robot project ......so here is the issue i facing now :

. I need to drive a Infrared LED, .. and the LED works when it under the defaul testing conditions list on data sheet.

But i need to drive the LED by the Microcontroller pins, but the pin has a very smaller output voltage and current than the default LED testing condition.

If i use an Op-AMp to amplify the pin output , that might works , but another drawback is the 741 Op--AMp need a +15 and -15 power supply ,maybe the battery will increase the weight of my robot ........ so is there any other approach i can amplify the signals????

BTW, anyone can tell me if not the Square wave can be amplified by Op-amp???

thanks for any helps ..
 
A transistor according to the common emitter configuration for switching purposes.
Square waves don't need to be amplified with op-amps if they come from the PIC. You can use a transistor also for this purpose.
 
Vizier87 said:
A transistor according to the common emitter configuration for switching purposes.
Square waves don't need to be amplified with op-amps if they come from the PIC. You can use a transistor also for this purpose.
Click to expand...

thanks for your advices ,,, i will try

BTW, did the transistor power supply Vcc, has to be 15 v ??? I think it could be 5V regular .
 
switching on a IR LED? yeah.. 5V regulated is good enough for moderate ranges.. My friend's reached half a meter. You can add the range using lens if you want.
 
i just thought that if i use NPN　transistor , it has Vbe = 0.7 v ,as the turn-on voltage. Howerver, my output voltage from MCU is only 0.2V.....

so i still need an amplified input voltage for turing on the transistor first..........
 
That doesn't seem right. I could buy a voltage threshold of .2V for a logic one on an input but not .2V output voltage. A transistor will work fine.
 
fire an infrared beam? you can't even see infrared unless you're simulating a combat using a webcam for surveillance.
 
Status
Not open for further replies.

Similar threads

R
  • Question
Need programmer against payment ...
Replies
5
Views
6K
Electroplater
B
Help needed with garage door control for robot lawnmower
Replies
15
Views
12K
For The Popcorn
F
L
Help building single revolution motor/servo/stepper circuit
Replies
6
Views
9K
shortbus=
S
G
  • Question
Help wanted to power an AC120v induction motor ( edited from Brushless motor - thank you @SHORTBUS= )
Replies
9
Views
9K
MaxHeadRoom78
T
Help with a simple circuit please
Replies
12
Views
9K
sekemiat ke
S
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…