# Tag Info

### How to calculate the base current of the transistors in this voltage regulator?

Trying to do a DC analysis is going to be difficult because there are active devices and feedback involved. The base current is going to be whatever it takes to cause the current through the load to ...
• 12.3k
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### Do I need to use a voltage regulator or an overpower protection

You don't need either because you want to power a boost converter from the output of this. It makes no sense to reduce 12V down to 5V and then up to 18V - just convert it directly to 18V. Switching ...
• 10.6k
1 vote
Accepted

### Minimum and maximum input voltage for boost converter for reliable operation

From what I understand from the schematics given on p.2 of the schematic, it's 0.9V for 3.3V output, and 3V for 5V output. And the datasheet defines a start-up voltage of 0.82V but the related note ...
• 24k
1 vote

### Minimum and maximum input voltage for boost converter for reliable operation

Here is the start up conditions ... And here is : Maximum input voltage <= Vout < 5.5V
• 10k
1 vote

### Minimum voltage power supply

You can use a boost converter to convert the varying input voltage to a stable (i.e. 12V) output voltage. There are a lot of ready-made modules you can buy. This of course won't work if the voltage ...
• 13.3k
1 vote

### RT9080-33 LDO voltage regulator: enable chip with +5 V and GND

You have not mentioned how much is BATT+ voltage range. I assume it is say 4.2V typical. In the case where device is not charging and when jumper is not connected to GND. Here you want EN to be 0V ...
• 1,223
Accepted

### Module with LM7815 and LM7915 voltage regulators has 3 pins for input and output - why?

It has two voltage regulators on board, and can handle two input voltages, positive and negative plus common ground, and has two outputs, one for the +15 V, one for the -15 V, plus common ground. The ...
• 8,455
1 vote

### Module with LM7815 and LM7915 voltage regulators has 3 pins for input and output - why?

It needs positive, negative and common ground input to regulate positive and negative output in relation to the common ground output.
• 114k
Accepted

### LM317 output too low

Based on the resistor values, there should be 0.4V on ADJ pin which you have, and there should be 1.65V on OUT pin, which you have. The circuit works as per the schematics. The resistors are just ...
• 114k

### Power Distribution

the regulator L7805 is a three terminal positive voltage regulator, it can provide output current up to 1.5 A. You also should add some filter capacitors in the input and the output of the IC. The ...
Accepted

### What is the simplest way to adjust the input voltage for a linear regulator?

I would cut the trace after the MB6S's positive terminal and replace it with a 15V zener, like this: This way, the input cap will 'see' around 19V, which would be in spec.
• 5,104
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### Is there any voltage regulation on this board from an Apple Trackpad teardown?

Yes; circled in red below. At least three, including one most likely onboard the Broadcom chip, as you note. Regulators are fairly easy to spot as they are almost always paired with inductors -- ...
• 14k
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### How to use the "Sense Function" of RT9080?

A regulator senses its output voltage and then uses that signal to regulate voltage. The sense pin is used to sense the output voltage: (Taken from the datasheet) If you buy the version with the ...
• 13k

### Full form of LEB in VIPer01 block diagram

Leading edge blanking is used especially on current sense analog inputs where during the switching event, there will be some parasitics in your circuit, mainly stray inductance and semiconductor ...
• 10.6k
1 vote
Accepted

### Is this way of maximum current calculation correct for this voltage regulator?

The reason for the 500mA rated current is actually much simpler than that: The chip has an integrated current limit that may be as low as 600mA depending on tolerances (typically 800mA). Even if the ...
• 13.3k
1 vote

### Regulator output voltage drop in high temperature

The EN6360QI regulator itself is rated for 85 °C, so that should not be an issue if these are genuine EN6360QI parts. Some things to consider: Is the supply voltage within spec's (2.5 - 6 VDC)? Are ...
• 3,278
Accepted

### Safe Operating Area

If you look at the bottom axis of that chart you see that at a $V_{in}-V_{out}$ of 7 V and $T_A$ of $85^\circ C$ the current is around 1/4 A, so a 2 A load at that voltage is not okay by the ...
• 12.3k

### Buck converter (MAX5035D) regulation problem

Here's my ideas on the matter: The inductor value is too small. The equation calls for 44uH at least vin=[15 25 31]; vout = 10 ((vin-vout).vout./vin)/(0.32*125e3) ans = 4.4444e-05 8.0000e-05 9....
• 72.6k

### LM317 voltage regulator varying voltage output depending on the load

Others have pointed out that your values for R102 and R103 are far too large. One of the purposes of R102, besides setting the adjustment pin potential, is to draw current from the LM317's output, ...
• 16.9k

### LM317 voltage regulator varying voltage output depending on the load

As pointed in the other answer (and now done), reducing R102 to the recommended 220Ω (and R103+R104 in proportion) can improve things. Other ideas: Make sure the wiring resistance from VOUT to load ...
• 1,238

### LM317 voltage regulator varying voltage output depending on the load

All regulators have varying output voltage due to varying output current. It is hard to say how much in your circuit the current varies, and for the LM317L the change could be 1.5% over full ...
• 114k

### Which voltage regulator should I choose to power STM32 + 4G module + GPS with low consumption when they're in stand by?

I powered two ESP32 + SIM808 + RF module + DS3231 in my project by CN3903 3A dcdc. This one is step down from 36-5 V to 3.3 V. Work's fine for me.

### How to get a constant 5 V power supply when using the same power supply for motors and micro controllers

There are several possible causes. The current loop formed by the batteries and motors is a big electromagnet. Every time motor current rises or falls, that loop's changing magnetic field couples to ...
• 16.9k