Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

16f876A directly interfacing repay?

Status
Not open for further replies.
neazoi

neazoi

Advanced Member level 6
Joined
Jan 5, 2008
Messages
4,119
Helped
13
Reputation
26
Reaction score
15
Trophy points
1,318
Location
Greece
Activity points
36,918
Hello, I need a little bit of help here
I would like to use the 16f876A or similar 28-pin micro to switch on/of some relays.
If the relays have a 5V coil, can I switch them on by directly connecting the microcontroller pin to the coil, or do I need a transistor switch?

I prefer driving the relay directly but I do not know how much current can the micro provide on each pin.

The relays coils datasheet is this one https://www.techno-star.biz/relays/ea2.pdf


Also what about latch type relays, which require current only when switching? Would I be able to directly drive their coils using the micro?
 

it is recommended that you need a transistor to switch the relay other wise it may damage your controller...
 
  • Like
Reactions: neazoi

    neazoi

    neazoi

    Points: 2
    Helpful Answer Positive Rating
Even if I use latch type relays?
What is the max output current of the 16f876A btw?
 

I agree with hussain_kiet to use a transistor such as a BSP130 D-MOS logic level FET to drive the relay. Also if the relay is switching high currents or voltages an opto isolator before the replay is a good idea.
 

It depends on the type and number of relays.
If number of relays is more than 1, I would personally prefer using a ULN2003.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top