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.

IC used for On Off switch

Status
Not open for further replies.

PA3040

Advanced Member level 3
Joined
Aug 1, 2011
Messages
883
Helped
43
Reputation
88
Reaction score
43
Trophy points
1,308
Activity points
6,936
Dear All Have a nice Day

Please find the attached image which have an IC in side the red cycle , I need know the part number of it and operation

Top of the IC has number called 46 that all

I assuming this IC is used as an ON-OFF switch when the micro switch is press which is near the IC in the picture the system may ON when it press again system OFF

please advice what is the part number of it IC.jpg


Thanks in advanced
 

Hi,

FWIW, it could be a flip-flop/latch of some kind, maybe SOT-23-6.
 
  • Like
Reactions: PA3040

    PA3040

    Points: 2
    Helpful Answer Positive Rating
Thanks for advice
Package SOT 23 - 6 is correct and thanks for it

then how may i find the part number

any ideas

- - - Updated - - -

please find more clear picture
2.jpg
 

Attachments

  • 2.jpg
    2.jpg
    240.7 KB · Views: 175
Last edited:

Hi,

Diffficult. You (unfortunately) just have to be patient and go through SMD part code website indexes looking at entries for "46" and/or randomly search for phrases like "flip flop smd code 46" or "jk latch smd code 46 sot-23-6", etc. and do all that hoping that the number 46 is the actual IC code and not an internal company code...

It might help to 'scope the pins of the IC which might help to show which is V+, V-, the inputs and outputs and in this way see if any pins change state and latch when the button is pressed - that would at least help to guess if it is a JK latch or D flipflop by comparing what you observe and what pin and functional descriptions are for different types of latches and flipflops, etc.

Best of luck.
 
  • Like
Reactions: PA3040

    PA3040

    Points: 2
    Helpful Answer Positive Rating
The photographs are not even of the same board!
Please help us to help you by at least telling us what the boards are part of.

Brian.
 
  • Like
Reactions: PA3040

    PA3040

    Points: 2
    Helpful Answer Positive Rating
I found MAX16054 which is same to what i searched but it is bit expensive for commercial product

Still searching low cost solution

- - - Updated - - -

The photographs are not even of the same board!
Please help us to help you by at least telling us what the boards are part of.

Brian.
Thanks for the help and reply
The board is product of pololu power back boost converter

Please help
 

Hi,

I have never used that part. I had a quick look at the datasheet and as it says max. 8V for the pass device, I guess you'd need to clarify what working voltage (and current, maybe, although that would be a highly unlikely "need-to-know" for a pushbutton I would have thought) your circuit sees.

More importantly, to say the least, is that "The TPS27081A device is a high-side load switch that integrates a Power PFET and a Control NFET in a tiny package." - that's not a flipflop/latch. It is only momentary, not latching. Load switches are basically for power applications.

So, I think to answer: "I think this Ic can be implemented as an soft on off for power on and off", the reply is yes, it can (if you add some additional circuitry for the soft on and then some more for the soft off features) but I think we can agree that your original question was about a latching IC, so I'm not sure if you're now asking about a different part of your circuit design or are still looking for a flipflop/latch replacement. If it is the latter, you'd need to go back to some/any semiconductor manufacturer's parametric search lists and look for a bistable IC.
 
  • Like
Reactions: PA3040

    PA3040

    Points: 2
    Helpful Answer Positive Rating
d123 Thanks for info

Yes my original question was to identify the IC number in the given image. finally I could not fine it and I tried to search equivalent IC to the operation
Today I have fount following IC which is closely equivalent to the IC in my first post


I would consider looking at the TPS22915 or the TPS22918.

But still I dont know that it is the correct IC for my


In my case I am using Micro switch to ON and OFF the system , In this case when switch pressed it goes HIGH and it goes LOW once it released soon

Please let me know that in the above condition current flow from VIn to Vout (TPS22918). even switch is released and in the next switch pressed Vin and Vout should disconnected

Please advice

Thanks in advanced
 

Hi,

If all the IC needs to do is be on (the output be high) when the microbutton is pressed and off (output low) all the time the button is not being pressed, sure, any of those would do, or some buffer IC like the SN7407 up to 5V or the CD4050 up to 18V (but as they are six devices per package/IC, you'd need to look for that same function in a single device package/IC), or a logic gate even, or maybe just a little old series resistor. However...

If I'm wrong, correct me, please:
· Your application/design does not need a high-side switch IC or low-side switch IC because that group of IC are for power applications and you only need a low voltage signal function for the IC.
· Your application/design does require a latching device that when pressed once its output goes high and stays high until it is pressed a second time and then its output goes low, when pressed for a third time its output will go high again, and so on forever.
· You do need to send a low voltage signal from a microbutton to a microcontroller I/O pin. You don't need to send a "high" voltage or a large current into the microcontroller I/O pin.
...Is all or any of this correct?

If we are looking for a flip-flop, I looked quickly for specifically SOT-23-6 flip-flops and here are two different vendors' search results you can look through. I'm not promoting anything, just using these links to show you what I mean and I think Brian also believes you need to replace the mysterious SOT-23-6 called "46":

Texas Instruments SOT-23-6 Flip-Flops
Logic - Flip Flops

Here is an example of one possible IC I think you need for your design/application made by two different manufacturers:
SN74LVC1G175 Single D-Type Flip-Flop With Asynchronous Clear
NC7SZ175 TinyLogic UHS D-Type Flip-Flop with Asynchronous Clear

It functions from 1.65V to 5.5V.

Let's see if we're getting closer to what you're looking for, hopefully. :)

- - - Updated - - -

In my case I am using Micro switch to ON and OFF the system , In this case when switch pressed it goes HIGH and it goes LOW once it released soon

Please let me know that in the above condition current flow from VIn to Vout (TPS22918). even switch is released and in the next switch pressed Vin and Vout should disconnected

...Now I understand what you mean. Sorry, the answer is no, it will not. As well, the TPS27081A, TPS22915 and TPS22918 do not include any soft start and soft off functionality inside the ICs. The TPS22918, etc. (high-side switches) are only high at Vout when Vin is high. I explained it a bit in what I just wrote above here, too.
 
  • Like
Reactions: PA3040

    PA3040

    Points: 2
    Helpful Answer Positive Rating
d123 Thanks for info


Please fine the what I should required

CCT.JPG

The above image is used LM2576 power regulator . I need to connect it EN pin ( ON OFF pin) to soft on off ic

Hoped you can understand

Once again thanks for you grate reply and time you spend for me
 

Hi,

Hoped you can understand
To me it´s not clear...

Please in future use standard schematic symbols (instead of PCB footprint and blck boxes), draw the signal flow from left to right, audn give voltage levels and timing...
Hand drawn is OK. All symbols can be easily found in the internet...

Klaus
 
  • Like
Reactions: PA3040 and d123

    d123

    Points: 2
    Helpful Answer Positive Rating

    PA3040

    Points: 2
    Helpful Answer Positive Rating
Hi,

Looking at the IC (LM2576) and how it works (wide supply range from ~5V up to 40V), you really need to say what the supply voltage is, please.

Is the soft on/soft off for the LM2576 enable pin or to have a slow output voltage rise to e.g. 3.3V and a slow output voltage fall to 0V?

Enable is either on (0V to 1.2V) and the output at e.g. 3.3V or off (1.4V to 2.4V) and the output will be at 0V. I don't see why a soft start/stop is of practical use on the enable pin - I assume it will either need to be on or off but not enjoy slowly passing through "grey zone" moments as it is basically a logic (0 or 1, never 1/2 way inbetween ideally) input, in my opinion.

If it's the output of the LM2576 you want as soft on/soft off, it depends what Vout of the LM2576 is connected to before any useful suggestions might be made.

Explain the soft on/off in much more detail, please. Is it soft start/soft stop, with a rising and falling slope?

I'll be back later because first I want to think about how to do the LM2567 enable pin active low input part + latch + microbutton.

- - - Updated - - -

Hi,

This simple latch uses the ("old-fashioned") TTL SN74LS74 Dual D-Type Positive-Edge-Triggered Flip-Flops with Preset and Clear, I imagine it is functionally the same or very similar to the two single device ICs linked to in post #11, or the CMOS CD4013. According to the simulation results, the !Q output would be the one that is connected to the LM2576 enable pin (with a 10k to 100k or even 1M pull-down resistor).

flipflop lm2576 enable pin and microbutton schematic.JPG

This should solve that part of your requirements, all you need to do now is select a flip-flop (single, dual, quad) and package available where you live/from a supplier.
 
  • Like
Reactions: PA3040

    PA3040

    Points: 2
    Helpful Answer Positive Rating
Grate thanks for detailed info


It is answered by d123 which I see later that you have modified the answer

Thanks once again

Just simple question that you mention it is old
fashioned


 
Last edited:

Hi,

I'm glad the button-latch is a suitable solution.

Just simple question that you mention it is old fashioned

Well, I think IC product lines like TTL SNxxxx, etc., or CMOS CDxxxx are considered "old" ("classic" might be a fairer word) by some people, especially as nowadays it's seemingly more normal to use MCUs, the Pi, Arduinos, FPGAs and so on.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top