Atmega 32a problem

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How to proper power supply for atmega32a
.i am useing 15-0 transfomer brige rectifire and
1000/25 Capacitor 7805 and .1uf cap but some time 16x2 lcd display show ?????? Mark and hanging press key butten not responding.
(i my area lote off motors solnoid relays working )
Please help me proper power supply circuit

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Last Edited: Thu. Feb 7, 2019 - 05:05 PM
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Best you first draw a schematic of how you actually wired everything, there must be more connections than you have written about.

for a start a 100nF capacitor to me seems to be on the low side for 5V decoupling, so your supply might not be stable enough, but a quick look with a scope should get that sorted.

How is the programmer connected?

 

What have you done with the fuse settings?

 

How far are you sure your code is actually working?

if you just initialize the display and write " Hello Sam"  to it, does that show?

 

At this point a lot is unclear and can be wrong.

 

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Sir please see 5v side 0.1mf (0.1uf) 1000mf(1000uf/25) atmega32a microcontroller

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A schematic would be easier to read!

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The first thing I notice is that the capacitors on your crystal are labelled as being 0.1uF. That is very wrong. They should be around 18-22pF.

#1 This forum helps those that help themselves

#2 All grounds are not created equal

#3 How have you proved that your chip is running at xxMHz?

#4 "If you think you need floating point to solve the problem then you don't understand the problem. If you really do need floating point then you have a problem you do not understand." - Heater's ex-boss

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That is a bit more than just a rectifier a couple of caps and a LCD.

As cliff said a schematic will be easier to understand for most of the people here.

 

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No no pcb disiner mistak is 22pf 8mhz cristal and i post my scematic

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Even without a schematic I see a number of problems...

 

1) Putting two linear regulators in parallel to increase the current, or decrease the dissipation, is a terrible idea. What happens if they have slightly different output voltages.

 

2) Putting a 1,000uF capacitor on the output of a linear regulator is not recommended. You need 100nF close by and no more, plus the local capacitors for each chip.

 

3) Your power supply tracks are too narrow, especially the 0V rail.

 

4) Your power supply tracks are too long, especially the 0V rail.

 

5) How much current do you think you need on the 5V rail? That 100R resistor is going to get very hot.

 

6) Why the components (I assume they are zeners?) across all the supply rails?

#1 This forum helps those that help themselves

#2 All grounds are not created equal

#3 How have you proved that your chip is running at xxMHz?

#4 "If you think you need floating point to solve the problem then you don't understand the problem. If you really do need floating point then you have a problem you do not understand." - Heater's ex-boss

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And also...

 

7) The 100nF capacitors across the AC are in the wrong place.

 

8) Ditto the 100nF capacitors across the 1,000uF smoothing capacitors.

 

9) Because your 0V rail is so narrow and so long the 100nF capacitors on the mega32 will not do anything.

 

10) Aref should not be connected to the 5V rail, only to a capacitor.

#1 This forum helps those that help themselves

#2 All grounds are not created equal

#3 How have you proved that your chip is running at xxMHz?

#4 "If you think you need floating point to solve the problem then you don't understand the problem. If you really do need floating point then you have a problem you do not understand." - Heater's ex-boss

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And also...

 

11) The SIL resistor pack near the mega32 pins 14-20  has an incorrect silk screen as your have the 5V rail connected to pin 9 and not pin1.

 

12) Do you really need all those pull-ups resistors on every IO pin? Can you not use the internal resistors?

 

#1 This forum helps those that help themselves

#2 All grounds are not created equal

#3 How have you proved that your chip is running at xxMHz?

#4 "If you think you need floating point to solve the problem then you don't understand the problem. If you really do need floating point then you have a problem you do not understand." - Heater's ex-boss

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Sir i am not enginear i learn arduino on youtube
And i use atmega core please help me what i change

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You still need to post your schematic.

 

#1 This forum helps those that help themselves

#2 All grounds are not created equal

#3 How have you proved that your chip is running at xxMHz?

#4 "If you think you need floating point to solve the problem then you don't understand the problem. If you really do need floating point then you have a problem you do not understand." - Heater's ex-boss

This reply has been marked as the solution. 
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clawson wrote:
A schematic would be easier to read!
In this particular case the PCB layout is far more telling than the schematic.

 

- Not even an attempt at a ground plane.

- Switching current trhough the Triac goes all over the board (Separate the current paths !!! ).

- All of the posts above.

- Put some inductors and / or choke's in the power supply traces. (HF stuff goes right through voltage regulators, and goes "around" most capacitors.

- Put more small (100nF ) ceramic capacitors on the board and put them close to each Vcc/GND pair of each IC (and LCD connector).

 

I'm in s sort of dilemma here.

Giving proper advise wouls probably take hours, and I don't want to invest so much time.

For a first attempt at making a board, it must have been quite a project to get this far, but it is clear you're still learning and have missed a bunch of basic rules about PCB layout.

A well designed PCB is not just a bit of copper to make electrical connections, but a lot of thought goes into it to make a product reliable and behave well under all circumstances.

For example, the link below points to a PCB with the size of a phone (because it is a phone smiley ) and after the schematic was finished they needed a whole month to do the initial board layout, and (a few) weeks more to clean the layout.

https://puri.sm/posts/how-we-designed-the-librem-5-dev-kit-with-100-free-software/

 

"PCB layout" is a separate and important skill in the design of a product. Take this first board as an example of what happens when the board is not well made, and then go on and find some tutorials about laying out the PCB traces and EMC "stuff".

Doing magic with a USD 7 Logic Analyser: https://www.avrfreaks.net/comment/2421756#comment-2421756

Bunch of old projects with AVR's: http://www.hoevendesign.com

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Please see my power supply right or wrong guide me

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What inductor connect and which pin i connect

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Put some inductors and / or choke's in the power supply traces. (HF stuff goes right through voltage regulators, and goes "around" most capacitors.

- Put more small (100nF ) ceramic capacitors on the board and put them close to each Vcc/GND pair of each IC (and LCD connector).

What inductor i connect and how to connect

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What is 0v rail i am not understand

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I'm sorry but that schematic is no help at all. It does not show everything on your PCB, and there are connections on your PCB that are not shown on the schematic.

 

Also...

 

13) I don't see any 5V going to your LCD display on the PCB.

 

 

#1 This forum helps those that help themselves

#2 All grounds are not created equal

#3 How have you proved that your chip is running at xxMHz?

#4 "If you think you need floating point to solve the problem then you don't understand the problem. If you really do need floating point then you have a problem you do not understand." - Heater's ex-boss

Last Edited: Thu. Feb 7, 2019 - 07:02 PM
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Aref how connect and which capacitor i use i dont which cap o use

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Aref how connect and which capacitor i use i dont know which cap I use

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My first disine easy eda pcd plese check power problem my single side pcb

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How many pcbs have you seen designed like that? Probably none. You could at least remove the jagged tracks.

 

Your schematic has major problems - sort them out first.

 

What use is the pc817 optocoupler if you don't have sufficient clearance? I suspect you really don't need it.

 

It looks like you've adapted an 8051 design - the AVR doesn't need pullups and the Mega32 has eeprom, so why the external one?

Last Edited: Fri. Feb 8, 2019 - 04:36 AM
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Uplode first pcb disine by pcb disiner i pay mani
Thats pcb problem so yesterday i tried disine single side pcb only i tried first time plese help what i mistake 5v power and aref pin line

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Pc817 optocupler .i use long wire to proxmatic sensor for machine use for counting that long wire go to motor nearly magnatic and indactive affect wire and mcu so i use suprate 12v du and optocupler
pc 817

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What is your back ground?

What education did you have in the field of electronics, and programming?

You do not even seem to know the most basic things, so I wonder at what technical level we should be talking.

If you have had the PCB you posted about custom made by someone that claims to be a HW designer I think I would ask my money back.

 

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Ok ok i go to technical expert