The Philippine Electronics and Technology Forum
February 10, 2012, 05:28:33 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Search Login Register  

The Philippine Electronics and Technology Forum > Academic Community and Professionals > Absolute Beginner Technical Discussion > opto input quetion
Pages: [1]   Go Down
« previous next »
  Print  
Author Topic: opto input quetion  (Read 532 times)
rage3657
Size AAA Battery
***

Pogi/Ganda Points: 2
Offline Offline

Posts: 78
« on: March 02, 2010, 04:22:41 PM »
guys!! am electrical tech and noob sa electronics, have 2 quetions here, found this drawing on olim3x site on their PIC IO board.  http://olimex.com/dev/pdf/PIC/PIC-IO.pdf
 [/img]


1. ano purpose ng 1n4148 connected across opto input leds?
2. sa manual ang sabi ..."Four opto-isolated inputs will allow to detect voltages in range +5-24VDC".  totoo ba to?? up to 24vdc?? with the same resistor value and wattage??

am learning thanks sa mga sasagot.
Logged
The Philippine Electronics and Technology Forum
« on: March 02, 2010, 04:22:41 PM »
 Logged
mArKhAo
Gas Turbine
**

Pogi/Ganda Points: 69
Offline Offline

Gender: Male
Posts: 2278


point and shoot
« Reply #1 on: March 02, 2010, 04:28:49 PM »
Quote from: rage3657 on March 02, 2010, 04:22:41 PM
guys!! am electrical tech and noob sa electronics, have 2 quetions here, found this drawing on olim3x site on their PIC IO board.  http://olimex.com/dev/pdf/PIC/PIC-IO.pdf



1. ano purpose ng 1n4148 connected across opto input leds?



protection....

Quote
2. sa manual ang sabi ..."Four opto-isolated inputs will allow to detect voltages in range +5-24VDC".  totoo ba to?? up to 24vdc?? with the same resistor value and wattage??

am learning thanks sa mga sasagot.

hmmm, baka merong specification sa data sheet...
Logged
cut my heart out, for a souvenir....
rdpzycho
Technical People
Solar Power Satellite
*****

Pogi/Ganda Points: 466
Offline Offline

Gender: Male
Posts: 9160


Perfection is an Illusion


WWW
« Reply #2 on: March 02, 2010, 04:31:49 PM »
1. reverse voltage protection, karamihan ng optoisolator mababa ang inverse voltage na kakayanin. since 'yung user ang magkakabit ng voltage doon sa input, kailangan may additional protection.

2. yup. kailangan lang naman ma-meet 'yung minimum current para mag-on 'yung output transistor.

sinagot na pala ni markhao. Grin
Logged
‎"Keep on starting, and finishing will take care of itself."

- Neil Fiore
piona
Gas Turbine
**

Pogi/Ganda Points: 112
Offline Offline

Posts: 2963


earth - evils = heaven
« Reply #3 on: March 02, 2010, 04:34:29 PM »
ito lang max ratings ng opto nyo...
Logged
love without accomplishing the laws, is complicated - sshrekk
rage3657
Size AAA Battery
***

Pogi/Ganda Points: 2
Offline Offline

Posts: 78
« Reply #4 on: March 02, 2010, 04:38:04 PM »
pero kung ipasok jan 24vdc diba masyado malaki un forward current di ba mag iinit un resistor ans magtatagal ba un opto coupler, if am not mistaken kung 24vdc forward current nya would be around 63mA
Logged
piona
Gas Turbine
**

Pogi/Ganda Points: 112
Offline Offline

Posts: 2963


earth - evils = heaven
« Reply #5 on: March 02, 2010, 04:41:07 PM »
^ yong R1-R4 na 330 ohms pang 5V input lang na dropping yan recompute nyo sa ibang input voltage.

....o di kaya baka yong Vce ng opto ang ibig nyang sabihin, para saan ba yang apat na opto ?
Logged
love without accomplishing the laws, is complicated - sshrekk
rage3657
Size AAA Battery
***

Pogi/Ganda Points: 2
Offline Offline

Posts: 78
« Reply #6 on: March 02, 2010, 04:44:12 PM »
Quote from: <')XXx< on March 02, 2010, 04:41:07 PM
^ yong R1-R4 na 330 ohms pang 5V input lang na dropping yan recompute nyo sa ibang input voltage.

Ahh ok then dapat specify nila yan sa manual ano. wala nmn ako balak gamitin yan nabasa ko lang sa website nila.

thank u sa mga sumagot ha.
Logged
rdpzycho
Technical People
Solar Power Satellite
*****

Pogi/Ganda Points: 466
Offline Offline

Gender: Male
Posts: 9160


Perfection is an Illusion


WWW
« Reply #7 on: March 02, 2010, 04:45:05 PM »
assuming low forward voltage 'yung LED, yup mag-iinit siya. most probably, high forward voltage 'yung LED, dahil 'di nila i-indicate na kaya 'yung 24V kung magiging masyadong mataas ang current.
Logged
‎"Keep on starting, and finishing will take care of itself."

- Neil Fiore
The Philippine Electronics and Technology Forum
   
 Logged
Pages: [1]   Go Up
  Print  
« previous next »
 
Jump to:  


Related Topics
Subject Started by Replies Views Last post
Saan po ako makakabili ng CNY70 na opto-coupler????
Electrical/Electronic Parts and Suppliers 		Naruto12 4 954 Last post September 19, 2008, 11:07:15 AM
by maldihtah13
audio input xformer at ic na 1.5 lng input
General Electronics and Technology Discussion 		fishbone000 0 206 Last post February 23, 2010, 03:58:18 PM
by fishbone000
opto isolator
Consumer Electronics, Appliances and Electronic Gadgets 		moira 3 529 Last post February 26, 2010, 12:24:00 PM
by Simatar
Opto-triac « 1 2 »
General Electronics and Technology Discussion 		su1c1d4l 20 1089 Last post March 10, 2010, 03:38:27 PM
by su1c1d4l
opto-isolator
Thesis and Project Proposal 		ayrtonshunt 3 364 Last post March 30, 2010, 11:00:06 PM
by ayrtonshunt
akira tv ct-21nk9a reg and opto missing
Television Repair 		marconikz 11 210 Last post July 20, 2011, 09:55:25 AM
by Triple_D
opto isolator
Analog Electronics 		coi12 2 231 Last post August 05, 2011, 08:00:20 AM
by slsiasat_14
Powered by MySQL Powered by PHP Powered by SMF 1.1.15 | SMF © 2011, Simple Machines Valid XHTML 1.0! Valid CSS!