The LM78LXX series of three terminal positive regulators is available with several fixed output voltages making them useful in a wide range of applications . LM78L05 ELECTRICAL CHARACTERISTICS. (VI = 10V, IO = 40mA, 0°C ≤ TJ ≤ °C, CI = µF, CO = µF, unless otherwise specified. (Note 1). Part Number: LM78L05, Maunfacturer: National Semiconductor, Part Family: LM, File type: PDF, Document: Datasheet – semiconductor.
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Many of these are are specially designed for an automotive environment check spec sheet in each case and will survive in places dataxheet an LM will be destroyed or will protect your 5V powered circuit in situations where an LM would allow it to be destroyed. I am going to pull at most 5 mA of current.
I’ll get back to it in a minute. Please post technical questions on the forum, not by personal message. The resistor will drop the input voltage and form a low-pass filter with the LM78L05’s input capacitor.
The 78L05 is a three terminal voltage regulator. For instance the Littelfuse 1.
The INA will work down to 2. Rated reverse standoff voltage is always lower than breakdown voltage. Adtasheet a say 10 uF and 0. Thanks for the “longish” answer Russell, you didn’t surprise me at all. Features Dropout voltage typically 0. A TVS is still a good idea though, since you’re working in an automotive environment.
LM78L05 Datasheet PDF – 5V, Positive Regulator – TI
During line transients, such as load dump when the input voltage can momentarily exceed the specified maximum operating voltage, the regulator will automatically shut down to protect both the internal circuits and the load. Especially if you read up on using sleep mode. But, the IC suffers from heavy heat loss hence a Heat sink is recommended for projects that consume more current.
The lower input voltage will allow you to choose a lower voltage TVS, however. This is a 5V. I don’t know lm78o05 schematic for an SD card. Only ceramic caps are low in ESR,ceramics will reduce the ripple up to the level that your bulk cap can handle.
Russell suggests using a series resistor, and I concur. The output current of this IC can go up to mA. But I have doubts. I would even go a step further, and also place a zener diode on the input, so lm78k05 you get a shunt pre-regulator. It always takes longer than you expect, even when you take into account Hofstadter’s Law.
Complete Technical Details can be found at the 78L05 datasheet given at the end of this page. I thought I wrote about the current, but I was wrong. Simple shunt regulator with zener diode preregulator to greatly reduce spikes: It is very easy and straight forward to use this IC, just connect the input in to the input voltage which has to be regulated and the ground pin to system ground.
So, LM78L05 needs bypassing for high frequencies, at most a 1uF? I know that I need at least a 10nF capacitor load in the output to limit high frequency noise, as per Note 4 in the electrical characteristics table.
The reason for this “required if more than xxx distance” requirement is that one of the things that the capacitor does is act as a short circuit for alternating current signals that appear on lm78l0 power rails and are unwanted. That’s where the smaller capacitors take over and provide bypass.
Voltage Regulator 78L05
To answer my own question, the schematics for both versions of the wave shield are found here, click on downloads. A capacitor across the zener further increases this effect.
It’s funny now I think the question was about capacitors: These “bypass capacitors”, as a rule of thumb, have to be located close to the devices being powered. I do not understand how the series resistor will drop the voltage?