monkhommey

i am helping with another MS project and coud use some help. i am going to build the above circuit from megasquirt.sourceforge.net to allow for knock sensing for a 1jz project. the problem is i dont understand electronic component part numbers well and dont know which parts to order.

i need help in picking the correct LM324 and NE555 to use to build this circuit.
i found the following:

NE555N - digikey # 497-1963-5-ND

this seems like it would work. i however do not understand the difference between 8-SOIC, 8-DIP,8-TSSOP,8-SOP ect. it appears to be a a socket/case description. 8 for the number of pins and a socket type or something.

LM324N - digikey # 497-1581-5-ND once again this is a 14-DIP. will this work for me and could someone explain to the village idiot what the designator after the dash stands for. thanks alot for your help.


also has anyone had any experiance with building this knock sensor input circuit?

Jobro

iTrader: (2)

I can help

DIP - dual inline pin package, this is what you want, all the chips in the MSI board are this layout

http://en.wikipedia.org/wiki/Dual_in-line_package

SOIC, I just call them SMDs http://en.wikipedia.org/wiki/Small-O...grated_Circuit

So you want your components to be DIP package.

I will try and help with the 555 timer and the LM324N

I'm not too familiar with 555 timers, and the part number for the opamp seems obselete.

I will have a look later for a datasheet and try to find something interchangable

monkhommey

hey thanks alot.! another question you might be able to help me with.. im building a few circuits on a seperate pc board to mount it inside the MS case. i bought a blank pc board from radioshack.. but the quality of it seems scketchy. do you know if there are better quality boards out there that you can usually find locally or are they all about the same?

Jobro

iTrader: (2)

I've used rather poor quality protoboard before fine. I know what you mean, it looks horrid compared to a professional board, but in reality its mainly just the masking over the top of the tracks making things like the V3.0 board and computer motherboards look pretty.

I'm fairly confident the quality if your soldering, the way you layout the components will be much more important.

monkhommey

so i found some more stuff out.. kinda.. im just guessing and you can tell me what you think.

ok.

so i searched NE555 at digikey.com because thats what the diagram shows.

i found various digikey compents like NE555N or NE555D. it would appear that the N designator stands for DIP as D stands for SOIC.. and so forth with others designators. so im kinda thinking that NE555N - digikey # 497-1963-5-ND should work. but also i found 2 manufactures with the same Manuf. part number- both had NE555N but one manufacturers product is rated at 6mA while the other is 15mA. im thinking that either of of these should work.. maybe ill buy the 15mA just to be safe..

Jobro

iTrader: (2)

I'm having a look now

Jobro

iTrader: (2)

This is for the LM324, I have had very good experience with TI OPAMP chips in the past. I would also suggest buying more than 1, at least 3 or 4 in case something goes wrong!

http://focus.ti.com/lit/ds/symlink/lm224.pdf

Digi-Key Part Number 296-1391-5-ND
Price Break
1
25
100
250
500
1,000
5,000
10,000
Unit Price
0.45000
0.36000
0.27000
0.18900
0.14940
0.12600
0.11700
0.11475 Extended Price
0.45
9.00
27.00
47.25
74.70
126.00
585.00
1,147.50
Manufacturer Part Number LM324N
Description IC QUAD OP AMP 14-DIP
Quantity Available 14,790

I was wrong about the obselete bit!

You can use the one you found,

this should also work, seems to be rated to sink/source 200mA

Not sure whether to believe the data listed in the catalogue or the pdf it links to.

296-1411-5-ND NE555P IC PRECISION TIMER 8-DIP Texas Instruments Timer - Single - - 4.5V ~ 16V 200mA 8-DIP Tube
15,236

1
0.45000

Hope that helps a little

Jobro

iTrader: (2)

When reading the pins off the 2N2222, that is an NPN bipolar transistor. You can remember its called NPN because the Arrow is 'Not Pointing iN' on the Emmiter.

Reading from top to bottom the pins go

Collector
Base
Emitter

The transistor is in a typical layout where when there is above threshold voltage on the base, there is current conduction between the Collector and Emitter.

Make sure you use a high grade of components in the circuit, paying particular attention to the Tantalum 10uF cap, if it is installed in the wrong direction its guts will blow out, or just a tiny dot will appear on the casing.

Make sure you do use the ceramic caps it suggests.

monkhommey

thanks alot!

so the "disk" type capacitors it notes in the diagram are ceramic? and the "tant" capacitor is Tantalum? i seriously know very little about board level electronic components!

Jobro

iTrader: (2)

Thats correct

You should be fine tho, digikey does sell a very high grade of component compared to what I can find in my country.