An IMPORTANT NOTICE at the end of this data sheet addresses availability, . Changed all text, tables and graphics to match the new data sheet template. LM Datasheet, LM PDF, LM Data sheet, LM manual, LM pdf, LM, datenblatt, Electronics LM, alldatasheet, free, datasheet. VOUT = 10V. PRELOAD = mA. OBSOLETE PRODUCT. DATA SHEET FOR REFERENCE ONLY. Consult for possible alternate source.

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Thank you for pointing it out Steve.

Email Required, but never shown. The second half of this doesn’t make any sense at all. The reality is modern parts make them easy to implement, reliable and quiet. That means the total linear regulator drops 3. Peter Mortensen 1, 3 14 Trying to bin chips for this is a waste of time, and clearly not the way to go. Hope it suits your requirements. Short story is that you can’t reliably or cleanly get twice the current from two paralleled voltage regulators that ostensibly produce the same output.

This also allows for lower valued resistors. Instead, the entire chip becomes the feedback loop. This difference between the input and output voltage is released as heat.

IC 7805 (Voltage Regulator IC)

Normally, as current approaches the limit for thethe presence of the 6R8 resistor drops enough voltage for the MJ PNP BJT to turn on and start supplying more output current. It may have something to do with that walls of text aren’t nice to read.

Most linear regulators have only a series-pass transistor to feed current to the load. A resource for professional design engineers.

All About IC | Voltage Regulator Pin Diagram & Schematics

I’ve seen it work. If IC1 has a minimum input voltage of 7. Thank you for clear explanation! Home Resources Learning Corner. A lot of energy is wasted in the form of heat. The datsaheet of the IC is a transistor Q16 that controls the current between the input and output and thus controlling the output voltage.


You can’t assume there can be two exactly identical chips. Misunderstood 5, 1 5 Sign up using Email and Password.

So, we now have 2 options. OP says nothing about the nature of the load, so that’s his problem. Without knowing what the application needs, especially if there might be EMI or reliability concerns, is blanket recommending a SMPS of any description a good idea? Then the “cold” regulator will take over and then it will overheat and really it ends in a bit of a power struggle no pun intended. When the ICs were introduced, the advertising called lm7805 “blowout proof,” meaning they would not be damaged by a short circuit and would turn off if they got too hot.

If we have a system with input 15 volts datasheey output current required is.

Capacitors will be beneficial in this case as they are good at maximizing voltage regulation. If not, I am looking for an IC which has Operating range from v and km7085 5v output.

Most additional current demand will be taken up by the transistor, not the regulator. A switcher would probably be a better solution. Here’s a decent looking circuit that adds two eatasheet around a to give significantly more l,7085 and short circuit protection: Switcher output can also be filtered for those low power but noise sensitive parts of the circuit. It’s true one of them will do most of the work, and would be more likely to fail than the other after months or yearsbut I assume your question relates to using up parts on hand rather than a production design.

If the regulator does not have a heat sink to dissipate this heat, it can get destroyed and malfunction. On the other hand, energy actually being used is:.


Just keep in mind that the filtered but unregulated input current to the regulator circuit must be greater in amperage than your desired output, in order to maintain regulation, if the input current drops below the set output current, there is no telling what can happen, from circuit damage, to oscillation of the output, which would be datasheett equivalent of feeding 5v Dtaasheet to your circuit being powered.

Monday, December 31, These circuits reduce the output current or shutdown the regulator, protecting it from damage in case of a fault. The bypass capacitors help reduce AC ripple.

Either design your circuit so that the input voltage going into the regulator is limited to dataeheet above the output regulated voltage or place an appropriate heatsink, that can efficiently dissipate heat.

Sure there will be more EMI than from a linear regulator it is switchingbut that’s not usually an insurmountable problem.

All About IC 7805 | Voltage Regulator

This keeps Q1 off, and things work as before. This might be mV or so at full output current of the combined regulator circuit. Circuit taken from here and there appear to be several variants of this on the web such as this: Another one And another The input voltage was monitored on an Oscope datasheef never changed more than a handful of millivolt downward, but the output of his circuit was a flat topped high frequency pulse in the Hz range.

Please enter your comment! There is also potential of causing one to overheat. Post as a guest Name. I agree that it’s not a good idea, but the question was “will it work? Please enter your name here. If the output voltage is correct 5Vdatassheet the voltage divider provides dwtasheet.