 Sangat bagus untuk berada di sini. Ini adalah tempat yang saya datang di Singapura 16 tahun lalu. Kita ada company yang bermula di sini, di tempat ini. Jadi, ia sangat bagus untuk berada di sini. Okey, jadi, saya hanya cuba menutupkan beberapa perkara tentang basis. Ini adalah tentang keputusan pengalaman. Sangat sedap konsep. Semua perintah di sini, tapi saya hanya ingin mengetahui beberapa perkara apabila anda membuatkan penyelesaian penyelesaian penyelesaian. Jadi, ini sangat mudah. Semua orang lihat ini. Ini penyelesaian penyelesaian penyelesaian. Saya hanya perlu menyebut bahawa saya akan memperkenalkan penyelesaian penyelesaian di sini. Jika sesiapa-apa nak tahu lebih banyak tentang penyelesaian, mungkin kita boleh mencubanya ke satu lagi sesi. Kerana kita ada banyak masa. Okey, itu adalah pembantu yang sukar. Apa yang kita nbuang adalah pembetugah penyelesaian penyelesaian penyelesaian. Satu subjects untuk memuntuhkan pembetugah, satu kimbahan dan satu pengistem каждый. Ituorro missiles yang yang recent. Macam mana perukses untuk memilih pembetugah penyelesaian. Apa yang kita benar? Bagaimana tetapi distributed cofert SEO? Melayuта staff si crane, You can just consider it as a very typical resistor whereby you have input voltage here, you have the load here and the relation of what it does is just vary its resistance to keep this point, the voltage at this point as a constant rate. So it's much simpler than you can think of, you just ignore the GNE link, it's just a resistor. So what actually happens is, it's just like you have two tanks of water and they load it here, the water drain and this miscorrector, he's just adjusting the valve to maintain this water level. So it's actually that simple. However, if you are looking for, I see you choose a chip, what you have to look at is, first of course you have to look at the output voltage, you want to 3.3, you want to 5, you want to 12, whatever. This is of course the first thing you will need to look at. Secondly is the output current. Of course, it will be on the datasheet banner. It's usually on the type of, for example this is a 1M regulator, this is all kinds of different output current, which is actually the maximum current that this regulator can support. We will talk about this much later, because it states that it is 1M regulator, that doesn't mean that you can really pull 1M power out of the regulator itself. There's much more things that you have to consider. And another thing, many people actually ignore the dropout voltage, it is actually, usually it's a very small session in a big datasheet, it's a very small session at table. For example, this is a very old, very popular LIM-17A series. Usually it will written as a voltage dropout voltage 2V. What does it mean that if you have an input voltage of 5V, you cannot output more than 3V. It will always drop 2. Minimum, it's either maximum or minimum, you have to look at the datasheet, for example there are other things. It will tell you that in a different condition, in a different low condition, it will drop 1.1V to 1.3V. So you always have to pay attention that sometimes your input voltage is just not high enough for you to get what you require for the output. And there are some better ones, the drop is very low, like 2M. And there are all kinds of different regulator you can choose. But usually for the dropout which is less than 1V or above 1V, it's called a low dropout voltage regulator. This is a lot different in the design of the chip, how it works, but we will cover something later in the later slides to see how different it can be and what you have to pay attention to when you select an LED regulator. Another thing some people usually will ignore is the tolerance of the output voltage. And in certain circumstances it's very, very important. For example, LM70A series usually they have a plus minus 4% of tolerance. Which means for example you have LM70O5 then the 4% of 5V is actually 0.2V. And what you will get is output from the voltage regulator you will have 4.8V to 5.2V. You cannot predict and it also doesn't mean that you put LM70O5 you will have variations of 0.4V or variations. The only means that you buy a batch of same chip then some are 4.8V, some are 5.2V and you have no idea but it's kind of a distribution and the center is 5.0V. And sometimes you have to pay to this and there are actually some better wise, high accuracy wise there is no 0.5% which usually is very expensive but there are certain in certain conditions you will want to have a high accuracy voltage regulator. So we talk about the output voltage then there are other things that will affect the output voltage for double temperature. Most of the time the temperature go up the voltage either drop or rise there is no guarantee you see how the design works and there is this thing called load regulation which is almost always in the data sheets and it tells what is the output voltage will change depending on what kind of load you are putting out usually the higher the load the lower the output voltage so you pull too much current from the regulator the output voltage will drop and usually it is it gives you as a percentage how much percent variation space over your normal output voltage and also there is another number in input when your input voltage changes the output will also change we just follow again they will give a percentage like 1% that means if your input has 1V variation then the output will be 0.01V variation and this all will show in the data sheet of a particular chip and of course noise from the input also sometimes coupled to the output depending on the different frequencies these all contribute to the output voltage but really not all circuits will have some bad influence will be influenced by the variation of the input voltage but to a certain extent sometimes there are certain things that are very vulnerable to supply voltage for example the most the most common thing is Arduino Arduino has an ADC and the ADC will use supply voltage as its reference so if your input voltage has a 4% variation then your output reading from the ADC will have 4% error so sometimes you have to pay pay attention to this if you design some higher positioning circuit and this is very important and this I think are wrong and I think this is the only case whereby the output voltage actually matters but when it matters the best the best thing is that you cannot offset it you cannot predict how much the input voltage variation is because there is temperature and the output reading will contribute to the output and you have to pay attention to this the other thing is a similar consideration and this is very important just now we say there is a 1A regulator do you really can pull out 1A from this chip you have to do your calculation for example we have a very simple diagram whereby we have 8V in 5V out and we have a home resistor as a load okay so home slot the output side 5V over 10 ohm you have 500mA current go through and the power will be 2.5W going from this resistor this is output current and the input side the regulator itself will just consume some of the current by itself usually it is called quencing current or sometimes it is called GND current so at the input side you have 505mA input over 8V input voltage that is 4.04W and what's the difference this is 1.54W of power actually become heat come out from this regulator chip so whether you have this regulator chip can hold this kind of power we have to do calculation you cannot just say this is doable or not doable how to do that look at these 2 numbers in your data sheet there are 2 numbers usually it is called optimal resistance one is called junction to case the other one is called junction to air we talk about junction to air first junction to air means that the heat going from the silicon inside this chip to the air without the heatsink so the unit is degree per watt what is the means that if there is number of junction to air it is 65 that means if you have 1W of energy dissipated from this chip stand in the steel air the silicon inside this chip will rise by 65 degree and this is rise by which means if your ambient temperature is 25 degree then you actually have 90 degree inside the chip and whether the 90 degree is okay or not you look at the operating temperature range if it is this chip the range is the higher range is 135 so it is okay if it is 1W and this package is standing in the air it is doable however just now the case we have 1.54W dissipated from this chip it actually will rise 100 degree and then if your environment is like 25 degree it is fairly doable it is almost hit the higher end it is actually very dangerous so please do a technician first then see whether you want to do that whereas the easy way is you have a heatsink for example you have a heatsink and what you can do now is you put a heatsink data sheet heatsink will give you a thermal resistance as well for example this one is 2.7W it is very low and what you can technically now is that you can use this thermal resistance junction to case what happens is the thermal will from the die to the case then go on to the heatsink and go into the air so now you can calculate this is junction to case this is case 2 heatsink usually this thermal component either the pinkish material there or some of the paste and there is a heatsink itself it is just like a series just plug them together and at times there is sufficient power you get how much degree you actually have will be rising inside the multireflator chip so this is modern enough and only in this certain case that you know I can actually pull out 500 million from this 1 amp multireflator that is how you have to calculate this is a case 2 heatsink case meaning by the packaging of the chip and the heatsink is that usually because it is not fully 100% thermal compound it can be either go through insulation material or some other things but usually it is very low sometimes you want to insulation the chip and the heatsink then put in some material silicon pad or something so that it is electrically isolated but it is a heat transferable so it doesn't shot itself it doesn't shot by itself so I have some slides later particularly think about that and one thing very easy to be ignored is called the minimum low current this especially applies to many of the LDOs it says that there is a minimum low current you need to draw more than for example here 5 million you need to draw more than 5 million from the output in order for the voltage to be regulated and sometimes if you draw too low especially if you have a microcontroller going to sleep mode and draw like several microamps then your output voltage actually not regulated it can go high or go low and there is no guarantee sometimes people just forget it and you just ring a circuit and you find why my output is not regulating this is the reason because you are not satisfied the minimum low current so how to satisfy this actually is very simple if you really cannot design a circuit to satisfy this one you just put LED at the output so you have power indicator and you also satisfy the minimum low current requirement or sometimes if it is adjustable regulator usually you have a voltage divided here and this divider will act as a load as well choose a divider so that the minimum low current is satisfied and especially to the LDOs that is very important and because this is a mistake that always happens even into famous companies and it is choose of the output capacitor we always know that there is output capacitor and how to choose the capacitance value you have to look into data sheet normally there is this paragraph inside the data sheet and for example this why it has the minimum output capacitance required by the MQ 2.7 is 10 micro far so you just choose this value but most importantly it will tell you that the ESR of output capacitor should be arranged between watt to watt so where you got this number you go to look for the capacitor data sheet and looking for the ESR and here the value 3 and 3 is in between 0.322 then it is usable otherwise financing will happen so what financing happen is this is MLCT multi layer ceramic capacitor it is cheap and it is very nice properties small and it has a very high capacitance but usually it has a very low ESR it is like for all of this one 0.12 0.012 0.1 it is very low what happens when you put this on 2.7 your output will have for oscillation i cannot guarantee it 100% oscillation but under certain low cost it will and there are several bad cases especially some of the product by this problem you can search internet you find this and they have to recall all the points because of this somebody put ceramic capacitor instead of alternative so if you really want to use ceramic capacitor you increase the ESR by yourself this is one thing that you can do the other the other method is you are looking for a regulator especially LDO which is designed for stable with looking for ceramic capacitor it is usually independent many of the newer generations of LDOs especially from linear or those TI they actually specify for use ceramic at output which is much nicer but also much expensive okay this is very important always check PR so everybody will I guarantee everybody will hit by this multiple times the reason being that 70A series everybody use this so everybody will know this is imported GND output and usually you can connect to the tab the tab is GND as well so you mount our c-sync and the case is very nicely done but M217 pin out is different the center pin is output and the tab is output you put this thing you screw out the case then you shut the output and this is not only the case M1790 series also reverse I just do not assume always check and the worst case this is the RK917 RK9166 it's a very nice regulator I always use this one but looking at the different there's a different part number and it gives you different pin out so when you order you have to check your part numbers carefully be server sometimes there's a suffix L and it's different pin out although it looks same is that the same so please always check this and the other thing usually the part number is not printed on the case case is too small so there's some other words printed here it makes thing it's like a track last slide there are two type of layout input regulator output which one will you choose looks very similar i will choose this one what is the reason you have to understand the GND pin the current flow to GND pin is only supply for the regulator itself it is not like too wide out so this pin actually have very low current flow you do not need to have a sick trace flow inside so this happens and because of the key, it is a hole here and all your current actually have to go through the hole then come back and sometimes after some stress the hole become broken or something you have problem of course the better thing is like this input output the two ground put together ground plane be okay much better if you have a ground plane will be even better usually the best thing is you do like you just forget about the schematic will have to left side input or right side you forget about it you do something like this and for all the things above much much easier and electric plane is much better of course another thing, put these two capacitors near the regulator itself so this are i think this is all i want to say about the voltage regulator you have written it right? ya ya