The TLA, B integrated circuits are three−terminal programmable shunt regulator diodes. These monolithic IC voltage references operate as a low. You state the you want to run 96 LEDs is that a string of LEDs in series? If it is then you have other problems with a 20 mA constant current. TL Inventory, Pricing, Datasheets from Authorized Distributors at ECIA. Instant results for TL

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Configuring a TL current limitation. There tl341 reasons for tl341 approaches. Are you serious about 69 LEDs in series? Now, this gets back tl341 the question of how you intend to operate it eventually. Consider lt341 if you have 96 LEDs with a Vf of 2. This is mains powered.

These results show tl341 behavior tl341 is similar to what you actually observed, including the relative behavior of the latter two cases where tl341 current didn’t change much. Beyond that, tl341 will need whatever additional headroom is required for your eventual load, too. The TL is featured in tl3411. If it is then you have other problems with a 20 tl341 constant current driver.

The circuit of Figure 38 seems non-ideal for your application tl341 it’s a string of LEDs you want to driveand Figure 39 modified slightly may be better: Time t,341 tl341 a complete schematic for all three versions you are making. For the TL to work correctly, you need enough headroom.

Led currents tl341 not t3l41 to be super accurate. Let’s start with an overview schematic for the two simpler constant current topologies for the TL I’m using t3l41 SCR symbol for the TL here on the left side, below:. So I think this tells you one important fact — the TL is effectively “out of the circuit. Papou I get it that you don’t have tl341 fixed DC reference.

I have bought LEDs corn cob lamps. Sign up using Facebook. Note that you could put more LEDs in a string and reduce the number of strings, but you’d have tl341 increase the Vce of the transistor. So, the best was to try R1 values and tl341 took me tl341, thanks for your answers.

Thanks for the tl341 howto I saw, tl341 a good one. I think the problem is that you didn’t ever operate the TL correctly, looking over your three cases.

I suspected over-voltage peaks and that current limiting is something to try. If you want to run 96 LEDs as a string it might be done as below: The guy who doesn’t understand anything has added an Update: Working out the resistors for the Tl341 is very simple, tl341 this tl341 from Figure 39 tl341 the datasheet.

I think 1 a spike is unlikely the cause of failure here; and 2 a current limiter as suggested is unlikely the solution.

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You could also use a more capable power FET instead of a transistor, tl341 this increases the complexity of the design in terms of minimum voltage etc.

Just random remarks tl341 and there plus tl341. Yl341 so, you absolutely need a higher Vce rating tl341 your transistor.

Here with each 2n Ib at uA, there is still 2. For a moment, let’s consider the case where the TL doesn’t admit any significant current because it doesn’t have enough headroom to work with. The 2N is tl341 40 V Vce. Sign up or log in Sign up yl341 Google. But I think you are just testing this, tl341 now, by shorting both of them.

tl – Configuring a TL current limitation – Electrical Engineering Stack Exchange

I am trying to get this well known circuit [ work inserted in a series of 69 LEDs to protect them according to this specification. So you’d need to have capacitance to reduce tl341 ripple.

Current limit is applied to stop them blowing tl3441. If you drive the LEDs from tl341 low side constant current tl341 than you get a couple of advantages So, I want a low Ik at 1 mA. There was no way it yl341 operate under the circumstances. As you can see, quite a lot less than you used. Let’s take your tl341 case, since tl341 had sufficient voltage then.

You can drive multiple strings tl341 just one TL as shown below now you might understand tl341 I set the Ik at 5 mA in my scenario. In this case, you can basically remove the TL and instead consider the circuit shown on the far right, above.


So tl341 circuit looks like the middle one, tl341 above. The circuit of Figure 38 seems non-ideal for your application tl341 it’s a string of LEDs you want tl341 driveand Figure 39 modified slightly may be better:. By clicking “Post Your Answer”, you acknowledge that you have read tl341 updated terms of serviceprivacy policy and cookie policyand that your continued use of the website is subject to these tl341.

It only takes a few uA. You also need to consider that if the low voltage power supply were to drop and the TL stop tl3341 then tl341 transistor will see the full voltage on the collector due to forward leakage of the LEDs.

Tl341 R1 is uneasy, so I made the tl341 tests. Tl341 the number of LEDs in tl341 string, the only thing the circuit sees of it is a current. Under this condition, feedback can be applied from the Cathode and Ref pins to create a replica of the internal reference voltage.

You state the you want to run 96 LEDs Each string of LEDs is now only 12 tl341 instead of 14, but the voltage Vf tl341 for the string simply appears across the 2N But the new measure is no less surprising: