
voltage regulator - Does 7905 needs minimum load current?
2020年6月8日 · In the 7905 negative voltage regulator datasheet, it didn't mention that it needs a minimum load current to operate. The 7905 that I have is outputting -7 V but adding a ~2 mA load causes the voltage to drop to nominal voltage -5 V. Input is -15 V. Does a 7905 need a minimum load or is it broken?
±5V using Voltage regulator L7805 and L7905, from DC input
I am trying to get ±5V using voltage regulator L7805 and L7905. The datasheet says to use AC source as input and transformer, but I am not really familiar with transformers, and I don't know if I ...
voltage regulator - How is the input of 7905 determined?
I have read that the max input voltage for this IC is -7V and max output voltage is -15.6V. According to it's name, the output voltage should be max -5V. I read this here. But for 7805 IC, the max
voltage regulator - Why does this 7905 giving -12V output?
The 7905 uses single sided regulation ie. it relies on the load to ground to pull, the internal transistor ...
voltage regulator - lm7905 LTSpice is not working - Electrical ...
2021年4月12日 · Works okay for me except output is not very accurate (-5.32V, which is out of spec). Maybe your symbol pins do not match the model or you are on the wrong node- it is better to name the nets you are plotting (F4 and, say, Vout) so there is no question of what node it is.
power supply - Electrical Engineering Stack Exchange
2015年8月17日 · I was originally just going to use a single battery (Maybe LiPo) with a voltage divider to provide a virtual ground connected to the common pins of both a 7805 and a 7905 to provide +-5V (For a microcontroller + numerous op amps), however, they have a …
power supply - Incorrect Output From 7805 - Electrical …
I am powering a few op-amps from a split supply made from a 7805 and 7905. Before connecting the amps, I measured the outputs from both regulators and got 5V and -5V, respectively. However, after I soldered down the amps, I observe -0.9V at the 7805 output pin (the 7905 functions properly).
Differences between LM317, AMS1117 and L7805
2016年1月26日 · I am trying get a 5V to power up AVR microcontroller. The power will be supplied either from 5V USB power adapter or from motorbike battery (about 11-13.7V). I have one piece of both 7805 and LM317
voltage regulator - Electrical Engineering Stack Exchange
Many variants of the 79L05 and 7905 need a minimum load, otherwise they produce a too high (absolute value) output voltage. Step one operates the 79L05 completely unloaded, which can cause -8.6V output even on a perfectly working part. If with a 1mA load (5k resistor) the voltage drops to -5V, your chip is OK.
power supply - Increasing the output current of LM7805
I have designed with LM317 and LM337, but I want to try with LM7805 and 7905. Simply I will have 5V output for 7805 and -5V output for 7905. However the output current is low. Therefore I should somehow increase the output currents. I've seen somewhere that it can be done with external transistor but I did not understand exactly how.