BGR (Band Gap Reference)

Рет қаралды 49,779

Күн бұрын

Video discusses about Band Gap Reference used in all ICs. Both circuit theory and Layout matching requirements are discussed.

Пікірлер: 118

@sigangsabaglari3606 2 жыл бұрын

Learning all these practical aspects of analog engineering while studying in prefinal year of college. I'm loving it.

@relali2009 Жыл бұрын

Thank you for these videos, I never get tired or lost. back in school it was easy to drift away from the lecture, now I know it wasn't me, rather it was the lecturer... thank you

@analoglayoutdesign2342 Жыл бұрын

Thanks for the feedback

@tranhuuthong07 Жыл бұрын

This is a great lecture, thank you so much, Professor! The content of the lecture is very helpful for me.

@analoglayoutdesign2342 Жыл бұрын

Thanks for the feedback

@kiran7640 3 жыл бұрын

This is the best video on BGR

@dtpx778 7 ай бұрын

Thank you really MUCH! In the script from my university it was explained horribly, but thatks to this video I got it ! Thanks

@analoglayoutdesign2342 7 ай бұрын

Thanks for the feedback.

@mahmoudsaad1179 2 жыл бұрын

thanks for all the knowledge u share with the world

@gauravhatwalne9394 Жыл бұрын

Very complex concept explained in very to understand language and that too in depth 🙏🙏🙌🙌 Thank you so much sir😇

@analoglayoutdesign2342 Жыл бұрын

Thanks for the feedback

@vijanvijan1936 4 ай бұрын

Ur really great sir....i get clear understanding

@asha503 3 жыл бұрын

Nicely explained...👍...All ur videos are very informative and explained well....helped a lot in clearly understanding so many concepts... Would like to see more videos in coming days...keep up the good work..All the very best for ur channel 👍👍

@sudhakarshrinivas 2 жыл бұрын

Very nicely explained sir. Please share the two stage opamp video of this part. Thanks

@dundu007 3 жыл бұрын

Nicely explained...

@bramhdevsingh9826 4 жыл бұрын

very nice and informative video thanks

@seekinggod3174 Жыл бұрын

Very clear explanation. Thanks for the education.

@analoglayoutdesign2342 Жыл бұрын

Thanks for the feedback

@abbashammoud7205 Жыл бұрын

Thank you ! Can you please add a video on how to integrate the opamp in CMOS and discuss the startup circuit ?

@analoglayoutdesign2342 Жыл бұрын

Ok will do.. thanks for the feedback

@hasliadiguliga3979 4 жыл бұрын

Hi Sir. I really enjoy watching your lectures. Thank you. The content is very helpful to me to understand the concept of the analog design. I am sorry to say this, the content of this slide is very good and understood, but the audio is very poor compared to other lectures (video). I am looking forward to watching your next lectures with good quality audio. Thank you and Thumb up!!

@analoglayoutdesign2342 4 жыл бұрын

sorry for the poor audio...will ensure that audio will be clear hereafter

@sudhirbabu6803 2 жыл бұрын

Well said Sir 👌

@sunkarasaigoutham 3 жыл бұрын

I didn't give much thought for why it is called BGR. The reason explained in the video is that Band-Gap voltage is 1.2eV and it is similar to Band-Gap reference voltage we get which is usually 1.2V.

@khs5054 Жыл бұрын

When calculated, Vref becomes Eg/q in case of T=0K. Read chapter Bandgap References in Design of Analog CMOS Integrated Circuit by Razavi.

@anilkumarpattapu4309 10 күн бұрын

Only it provides constant ouput v or i respective of temperature variations? It is not if voltage supplay varies will not vontrol,

@analoglayoutdesign2342 9 күн бұрын

This architecture provides constant voltage and ptat current. Sub 1v architecture provides constant voltage and ztat current

@amoghalokesh442 2 жыл бұрын

Hi, I am actually a new college graduate who is now working as a analog designer and your videos are really helpful. At 30:53 minutes you have shown a Sub 1V BGR and mentioned that will be discussed in a different video. Can you please upload a video on that particular circuit. It would be really helpful.

@analoglayoutdesign2342 2 жыл бұрын

Thanks for the feedback. Will make video on sub1v bgr

@amlande5597 Жыл бұрын

Yes pls make one.

@Gkcptplm 4 жыл бұрын

At 21:17 why only R1 is considered ? That path current should be decided by both R1 and R2 ,rt? Vt ln(n) is the voltage at + input ,so ideally current through R2 should be drain voltage of MP2 - Vt ln(n) divided by R2,rt? or am I missing something here?

@analoglayoutdesign2342 4 жыл бұрын

vtln(n)/R2 is the current in R2. That same current current comes from the current source MP2. So.. The drop across R1 is current flowing in R1 X resistance R1.... current flowing in R1 is nothing but current flowing in R2...which is Vtln(n)/R2...substituting it we get that equation... Current in the MP2 is set by the loop thru its gate... hope I answered...why we dont take voltage across MP2 is because its current source... current source can have any voltage across it..still current in it is same...we cant apply KVL across current source..hope this answers

@samudravishalmukherji7329 9 ай бұрын

Do you have the video for the start up circuit and also how to generate the IPTAT? can you please share the link?

@analoglayoutdesign2342 9 ай бұрын

Startup circuits can be found easily in search engines.. IPTAT is nothing but the current source that is for the bjt .. a mirrored one of that

@IKeraNI Жыл бұрын

Thank you so much sir, you are my king

@analoglayoutdesign2342 Жыл бұрын

Thanks

@211SANDEEP211 4 жыл бұрын

👌👌👍👍

@tejashreekulkarni5374 4 жыл бұрын

Hello sir.. It is a wonderful video which helped me a lot to understand.... Thank you .. could you please share the LDO and VCO videos also... that may help us ...

@analoglayoutdesign2342 4 жыл бұрын

sure..first ldo maybe later vco

@tejashreekulkarni5374 4 жыл бұрын

Analog Layout & Design Thank you

@vishwanathpatil9817 4 жыл бұрын

Thank you! Is there any way I can get these slides ?

@analoglayoutdesign2342 4 жыл бұрын

explanations will not be there in slides...I write it while recording the video...so slides alone will not be useful

@karthickkumar1380 11 ай бұрын

God You Saved me✨✨

@analoglayoutdesign2342 10 ай бұрын

Good luck

@piezero_567 3 ай бұрын

For ptat ckt. Generation are we taking beta of the bjt as infinite because only then base current is negligible....?

@analoglayoutdesign2342 3 ай бұрын

Here bjt used as diode.. it’s now variation of vbe as pn junction

@harshakanamarlapudi1681 4 жыл бұрын

Need of matching also to vary the Pvt variations ? Correct .?

@analoglayoutdesign2342 4 жыл бұрын

yes...matching is basically to counter gradients in fabrication...please watch semiconductor resistors video...

@ihk5648 4 жыл бұрын

You are an excellent teacher! Could you please explain MOS comparator / op amplifier in similar manner?

@analoglayoutdesign2342 4 жыл бұрын

thanks...plan is there for 5transistor OTA..soon..

@ihk5648 4 жыл бұрын

@@analoglayoutdesign2342 Thank you Sir!

@manideepabhi1171 3 жыл бұрын

Sir !! Please! please! .. ...Send ur mail id to mine.... vegyarapumanideep@gmail.com Plz sir i wont distub u much... I 'll list out and ping u once in a while..

@analoglayoutdesign2342 3 жыл бұрын

jt.analog@gmail.com

@alterguy4327 3 жыл бұрын

Here we could have used Diode connected MOSFET instead of Diode connected BJT, since both have same IV characteristics. Is there any specific reason for choosing BJT? Thanks for the video, It was really helpful

@analoglayoutdesign2342 3 жыл бұрын

ya..we can generate MOSFET based BGR, but there would be a need of two transistors with different Vt.we will need one extra Threshold adjust implant layer....it comes at a cost..... that becomes a hard constraint. on the other hand, we dont need anything extra when we use BJT based diode.... this bjt diode is parasitic bjt....substrate PNP... so doesnt impose any requirement on fabrication.

@analoglayoutdesign2342 3 жыл бұрын

so bjt diode is ubiquitously used...

@alterguy4327 3 жыл бұрын

@@analoglayoutdesign2342 Thankyou

@sunkarasaigoutham 3 жыл бұрын

are there any designs where bjt ratio is different from 1:8? Could you please point me to those designs? Overall very informative video. Thank you so much for sharing your knowledge. May I know which company do you work for?

@analoglayoutdesign2342 3 жыл бұрын

yes sometimes they use more...if unit size of bjt is small...it will be more than twenty devices...

@naresh490590 3 жыл бұрын

Thanks For the video. At 9:00 what is the Thermal voltage of the BJP, How it will increase when temperature increases, is it the junction potential ? if we connected BJTs in parallel how the PTAT voltage will become M times VT ?

@analoglayoutdesign2342 3 жыл бұрын

Thermal voltage is KT/q... Where T is temperature. This will be around 26mV typically. Its directly proportional to temp.

@bhaskarreddy3915 4 жыл бұрын

we take 8 bjt's for layout matching only ?

@analoglayoutdesign2342 4 жыл бұрын

8 and 1: together 9 bjts

@sardharvankunavath1988 Жыл бұрын

I am not able to find 2nd video can u provide

@analoglayoutdesign2342 Жыл бұрын

In the making

@hemantpise3414 3 жыл бұрын

what is the value for equation VBE2+VT ln(n)(1+r2/r1) here ln(n)=2 , (1+r2/r1)=11 , VT= 0.087mv/c. so what is the final ans? please explain calculation

@analoglayoutdesign2342 3 жыл бұрын

yes..all put together will be your bandgap voltage~1.2V.

@kamalprasad3293 2 жыл бұрын

Hello sir your explanation is very good, can you please mention better book names which is helpful for analog layout thankyou in advance

@analoglayoutdesign2342 2 жыл бұрын

Majority of the content is from internet search..

@saisethuramkolli9015 Жыл бұрын

Good Explanation, Can u please provide a link to reach you? If there is a simulation assistance for each Analog block in this channel, it will be helpful. As soon as possible. The content of this lecture is good.

@analoglayoutdesign2342 Жыл бұрын

You can reach me on jt.analog@gmail.com

@analoglayoutdesign2342 Жыл бұрын

Regarding simulation, even I have similar thought… but will see how to make that available.. thanks for feedback

@sagarverma4386 3 жыл бұрын

Thanks Sir for these lectures, Can we have some lectures on Impedance matching and Tuning circuits used in SERDES.

@analoglayoutdesign2342 3 жыл бұрын

those are advanced topics....let me plan for those...

@rutujakulkarni6161 3 жыл бұрын

Hi can you give link of second part.. i could not find it

@analoglayoutdesign2342 3 жыл бұрын

Its still not there.. Should record and upload.

@ashokkumar-kp1et 4 жыл бұрын

Any link for sub 1v architecture?

@analoglayoutdesign2342 4 жыл бұрын

I will be posting one more video on that..kindly wait

@maksudulhossainjewel378 3 жыл бұрын

Good lecture but too many ads!

@dennisylaya445 3 жыл бұрын

Thank you for the explanation sir. I tried to simulate bandgap voltage reference using hspice, unfortunately the operation region of the two pmos that I added in my op-amp to produce a bandgap reference is in cutoff region. Can you enlighten me as to why it operated in cutoff region?

@analoglayoutdesign2342 3 жыл бұрын

You mean the input diff pmos pair of the opamp?what is supply voltage , vt and technology?

@analoglayoutdesign2342 3 жыл бұрын

I generally advice to check BGR using ideal error amp.. So that u can check if circuit is working. Separately design opamp and check if that's working for the reqd range. Then replace ideal opamp with actual... This is my approach.. Think abt it..

@dennisylaya445 3 жыл бұрын

@@analoglayoutdesign2342 hello sir. can you check what's wrong with the values of the elements of my bgr? q1 gnd gnd vin- pnp10 area=5 q2 gnd gnd vr2 pnp10 area=5 mp1 vr1 vout vdd vdd pch w=20u l=1u mp2 vbg vout vdd vdd pch w=20u l=1u r1 vr1 vin- 100k r2 vbg vin+ 100k r3 vin+ vr2 1k vdd is 1.8v and i also used my own constant gm current circuit with 20uA.

@analoglayoutdesign2342 3 жыл бұрын

Hi Dennis, Bjt area will be 1:8 generally. R2:R3 ratio will be 10-12. Are u using ideal opamp? Please go thru the calculation Also look into example circuits and simulate them

@analoglayoutdesign2342 3 жыл бұрын

They will help u a lot

@SanjayKumar-wx1te 4 жыл бұрын

We have any thermal runaway effect due to BJT ??

@analoglayoutdesign2342 4 жыл бұрын

Thermal runaway happens when the BJT is biased for amplification(Ic=Beta times IB) and also there is substantially high current. Here we are using it as diode, secondly this is not a actual BJT. its parasitic substrate BJT. so the beta of this BJT will be only 5 or 10 unlike 100 of an actual BJT. Also the current that flows in will be in less than 10uA. the package will be able to quench the heat generated by such kind of temperature rise due to such small current. Hope this answers.

@SanjayKumar-wx1te 4 жыл бұрын

@@analoglayoutdesign2342 Thanks

@rajasekharnallamekala4950 4 жыл бұрын

Hi Sanjay ,in BGR ckt what is the purpose of bjt ? If u know tell me your answer

@SanjayKumar-wx1te 4 жыл бұрын

@@rajasekharnallamekala4950 Hi Rajasekhar , Diode current will have proportional temperature coefficient PTAT we can tell. Here Bjt are used as diodes, compare to actual diodes BJT created diodes will give better diode action. If we connect as diode collector and base tied here beta Ic/Ib =1 here always. If any change in beta due to external parameters. If beta increases is there any impact is my question. As beta increases temp increases and vice versa is thermal runway. Hope I answered your question.

@rajasekharnallamekala4950 4 жыл бұрын

Here bjt is diode cncted device ( collector and base shorted ) . IC equal to beta into Ib .. if beta value increses temperature Increses and thermal runway Increses ok . But in above msg sir mentioned beta Value is 5 to 10 only and IC equal to just 10 micro amp. Small amount of current can handle. Finally I am expecting in simple one word purpose of bjt in BGR is ?

@arun65394 4 жыл бұрын

Hello sir, At 36:0, In Vbg equation 1 Plus is not mention with Resistor ratio.

@analoglayoutdesign2342 4 жыл бұрын

When I calculate the output Bandgap voltage with respect to VBE1 then it will be only R2/R1.. but when I calculate the Bandgap voltage with respect to VBE2, then its (1+R2/R1)... just check if I am wright...

@surajsingh-nx6zl Жыл бұрын

Nice explanation but in cmos also we use npn

@analoglayoutdesign2342 Жыл бұрын

That’s BiCMOS process or BCDMOS process

@rajasekharnallamekala4950 4 жыл бұрын

In BGR ckt what is the purpose of bjt

@analoglayoutdesign2342 4 жыл бұрын

bjt will produce CTAT. please go thru the video again

@rajasekharnallamekala4950 4 жыл бұрын

@@analoglayoutdesign2342 ok

@jethrobo3581 8 ай бұрын

Video is superb, however I cannot interpret some of the words you are saying. Would love it if you could remake the video speaking much slower. Thanks.

@analoglayoutdesign2342 8 ай бұрын

To remake video is a huge effort.. however I will take care in future. Thanks for feedback

@srikanthSrikanth-to7jh 4 жыл бұрын

please sir do a video of current mirror 2 and apamp ckt with different layout matching techniques and how to do a perfect floorplan for any analog layout becease of these stuffs i didnt get a job please sir help to get a job

@analoglayoutdesign2342 4 жыл бұрын

sure...I will... just need time..

@hemantpise3414 3 жыл бұрын

why we used only parasitic pnp why not npn

@analoglayoutdesign2342 3 жыл бұрын

easy to construct...basically its diode that we need...for vbe

@hemantpise3414 3 жыл бұрын

can you guide us how to used mod gen efficiently

@analoglayoutdesign2342 3 жыл бұрын

i didnt get you

@hemantpise3414 3 жыл бұрын

I mean to say that modgen tool which is used for matching and some other purpose so can you make a video on modgen tool