HELP! 12V light controller

[weekendshock]

WOW! This is getting more complex than I ever imagined. Are you sure that this is not being over designed for the actual need? I would hope that by combining those other five in the Schmitt, it would turn on the transistor "harder" as has been suggested. If need be, I could go with one of those Darlingtons if that would give it a better range.
One of you stated that the metal can 2222 is much better than the black (plastic type) one. The original circuit that my freind built had the metal can type. A wire came off and I must have touched it someplace wrong and burned it out. I replaced it with Radio Shack (plastic type) and that is when I started to have most of these issues. I know that both have the same ratings. Is the metal can type that much better or about the same?

 

[KeepItSimpleStupid]

I did some searching and gor the followng numbers for package type vs PD
TO-15 75 mW
TO-5 60 mW

I don't believe the above values

TO-18 500 mW
TO-92 500 mW (plastic)
TO-18 500 mW
TO-92 625 mW (plastic)

Turning on HARDER basically means that the transistor has an Hfe,current gain parameter, (varies wildly), Ie = Ic + Ib; This the base current injected is mulltipled by Ie. The datasheet has a parameter called Ic(sat). Ic(sat). Thus you need to inject into Ib such that Ic(sat) is achieved.

The logic family has a certain amount of output which I didn't look up. You can parallel the outputs.

You MUST put the unused inputs to either Vcc or Ground.

 

[weekendshock]

Hello KISS,
I have duplicated the circuit that Ron sent me in his schematic. Thanks Ron, beautiful job! It came out very nice connection wise, if I do say so myself. The lamp turns on and off as intended and is adjustable for light sensitivity through variable resistor. Unfortunatly, the IC and transistor get hot, mostly IC. Interestingly enough the lamp does not even have to be in its socket, rendering this leg "open."
When I power up and shade the LDR the IC starts heating. When I add light to the LDR everything goes cool, showing me the circuit is turning on and off. It does not matter if the bulb (3X1watt LED) is being driven or not. I have gone through very carefully and verified it is exactly like the schematic???? I will explain what I have so you can verify that it agrees with the schematic. I tied together 3, 5, 9, 11 and 13 and also connected leg 2 (trigger/switch) into this group. I tied together legs 4, 6, 8, 10, 12 and conected this group to transistor base.
1K ohm resistor is connected to +v and connects to leg 1 of trim pot, one side of LDR and leg one of IC also connect at this point. The other leg of LDR goes to power ground as well as collector and leg 7 of IC (power ground). The emitter connects to one side of the lamp holder and the other side goes to +V.
It is using 5 of the six trigger groups to drive transistor base and is using leg 1 and 2 of IC for its original intended purpose which is to trigger the transistor and close ground leg to lamp holder and of course supply for the other five.
Please look over this schematic and see if you agree with it. I makes sense as far as turning on "hard" the transistor, but something is just not right. Could I possibly have a bad component? I do realize that the Schmitt is a CMOS and that it is static sensitive. I have been very carefull to make sure I am grounded to earth before I have any contact with it. At the point, I am at a complete loss.
Anxiously awaiting your reply and much needed advice. I must request, "Keep It Simple Stupid." I understand much better if you resort to layman terminology.
Best,
Jim

 

[ronv]

If you don't mind ordering a part, changing to a fet might be the easiest.
https://www.electro-tech-online.com/custompdfs/2010/11/NTD4858NPDF.pdf

 

[weekendshock]

Hello again,
CORRECTION!!!!!!!!!!!!!! In my last post I said resistor connected to leg one of trim pot and that is correct, but leg one of IC and LDR do not. They connect to leg 2 (center) of trim pot. Sorry, should have read again before sending.

 

[colin55]

There is no point in having one inverter drive the others. Put the 6 inverters in parallel.
You must have a 220R in the base from the output of the 6 gates.

 

[KeepItSimpleStupid]

PS: R is another way of writiing a decimal point, so 220R is 220 ohms.

 

[weekendshock]

hi,
The circuit that I built from Ron's schematic is really nice (pretty). Is there a way that I could splice a 220 ohm resitsor into this without complete reconfiguration. Is it possible to leave first inverter power other five to feed the base of transistor? Also why is power being consumed when I am not even driving the lamp? As I explained earlier, when power is supplied and transtsistor is switched on (dark condition) the IC begins to get hot, when I turn on a light, everything goes back to cool. Do I have a short while energized? If so, it is inside one of the components because I am confident that there is nothing physically wrong with my hard point connections Again, the LED lamp does not even have to be plugged in for the circuit to start over heating.
Is there anything between a 2n2222 and a TIP3055.

 

[colin55]

You are not allowing the outputs of the chip to go HIGH - that's why.

 

[KeepItSimpleStupid]

Mount the resistor on end. It will take up little space. Or.... Unsolder base lead. Flip up. Attach resistor. Use heat shrink if you have to.