2009年1月17日 · The LM317 I noticed got very warm, but not overly hot. I decided on the LM317 to regulate, because the source voltage can be from about 14.x volts when the alternator is running, or down to (say) 11.8 volts if the battery bank becomes depleted. Also I wanted enough head room voltage so that the LM317 would provide the constant 6.4 volts.

2025年1月5日 · I'm sorry, I guess that I wasn't clear enough. I don't need it as a Li Ion battery charger, I want to add a current limit circuit in order to make a lab power supply. my intention was to use a LM317 as a voltage regulator that will provide 0 to 30V and then to add current limit circuit - seems one like "crutschow" suggested, but with an additional power transistor, so that …

2020年5月30日 · LM317 and LM338 are easy to use and pretty straightforward devices for voltage regulation. LM338 is said to be able to supply 5A and LM317 more than 1A current. Just as an experiment I built two regulators, one with 317 and the other with 338. I used 220 ohms / 680 ohms which gave me an output voltage of about 5.8 Volts. So far so good...

2020年2月17日 · A resistor in series with the LM317 input will reduce the voltage, but I don't see a particular need for that here. For example, a 30Ω, 2W resistor in series will reduce the voltage by 5.7V at a 0.19A load current. The LM317 needs an input voltage about 3V greater than the output voltage, so for 3.3V output you need about 6.3V minimum input.

2016年1月17日 · The LM317 data sheet specifies the junction-to-ambient thermal resistance, in the TO-220 package, at 19 °C/watt. So if you're dissipating 12W, the internal die temperature would hit 12W * 19 °C/W = 228 °C, with the case only a few degrees lower.

2008年1月31日 · I agree with Steve about starting out on a switcher. The layout is critical. For your application assuming 9V in and 5V out and 100mA max average current you should be fine with the 7805 or LM317. If your currents will be higher and you are battery operated then you would enter the region where the complexity of the switcher becomes less of a ...

2016年5月4日 · The comparator reduces the regulation pin control voltage for the LM317 when the current exceeds the threshold set by the voltage reference U5 and pot U2, thus performing the current limit function. The current limit can vary from 1.2A to essentially zero current by varying pot U2, as shown for pot positions of 0%, 50% and 100%.

2011年7月28日 · As amazing as it seems I am having trouble locating an alternative Linear Voltage regulator for the LM317 with a Lower Drop Out Voltage and adjustable Output Voltage (Target 13.8V) and Current (Target - 400mA - 1.5A). Anyone care to take a …

2011年8月23日 · LM317 as a current limiter control: Confusing LM317 voltage regulator output: Need help to double check LM317 circuit: curious observation in using LM350/LM317: Help with lm350 /lm317 as Constant Current Source

2022年6月12日 · Why use a LM317 here ? Why not just use a resistor to load the TL431 and a output transistor. Why pick the NJW0302 PNP as the output ? WHy no feedback ? I have posted in a lot of places attempting to find out why this circuit was used. Its a really weird topology. Maybe there is some SPICE modeling that shows this maxes out some The weird behavior