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  1. #1
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    IC used for On Off switch

    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 Click image for larger version. 

Name:	IC.jpg 
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ID:	152566


    Thanks in advanced

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    Re: IC used for On Off switch

    Hi,

    FWIW, it could be a flip-flop/latch of some kind, maybe SOT-23-6.


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    Re: IC used for On Off switch

    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
    Click image for larger version. 

Name:	2.jpg 
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ID:	152600
    Last edited by PA3040; 26th April 2019 at 04:14.



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    Re: IC used for On Off switch

    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.


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    Re: IC used for On Off switch

    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.
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    It's better to share your questions and answers on Edaboard so we can all benefit from each others experiences.


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    Re: IC used for On Off switch

    I found MAX16054 which is same to what i searched but it is bit expensive for commercial product

    Still searching low cost solution

    - - - Updated - - -

    Quote Originally Posted by betwixt View Post
    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



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    Re: IC used for On Off switch

    This appears to be one of these:
    https://www.pololu.com/product/2809
    which is a switch module not a boost converter.

    I would guess the IC is a single flip-flop based on the specification.

    Brian.
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    Re: IC used for On Off switch

    Dear All Thanks for the advice and info

    I found following IC
    http://www.ti.com/lit/ds/symlink/tps27081a.pdf

    I think this Ic can be implemented as an soft on off for power on and off

    Please advice those who have use it

    Thanks in advanced



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    Re: IC used for On Off switch

    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.


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    Re: IC used for On Off switch

    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



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    Re: IC used for On Off switch

    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 - - -

    Quote Originally Posted by PA3040 View Post
    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.


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    Re: IC used for On Off switch

    d123 Thanks for info


    Please fine the what I should required

    Click image for larger version. 

Name:	CCT.JPG 
Views:	4 
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ID:	152714

    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



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    Re: IC used for On Off switch

    Hi,

    Hoped you can understand
    To me itīs 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
    Please donīt contact me via PM, because there is no time to respond to them. No friend requests. Thank you.


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    Re: IC used for On Off switch

    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).

    Click image for larger version. 

Name:	flipflop lm2576 enable pin and microbutton schematic.JPG 
Views:	3 
Size:	90.8 KB 
ID:	152721

    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.


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    Re: IC used for On Off switch

    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 by PA3040; 29th April 2019 at 16:41.



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    Re: IC used for On Off switch

    Hi,

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

    Quote Originally Posted by PA3040 View Post
    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.



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