Problem with Voltage Dividers

  • #1

Main Question or Discussion Point

i know this is a very basic question, but there's something i don't understand about voltage dividers.Vout is supposed to be(v2/V2+v1)* V, or the voltage drop across a resistor, but i don't see how this works in practice. When you put a load across the output, this changes the voltage drop of all the resistors in the circuit, so how is a voltage divider useful if you can't have a constant out value.
 

Answers and Replies

  • #2
370
8
When you put a load across the output, this changes the voltage drop of all the resistors in the circuit, so how is a voltage divider useful if you can't have a constant out value.
It's "constant" within limits. Quiz-Question: For Vin=10V and a desired Vout=5V, how would you design the voltage divider if you want to stay within, say, 5% your nominal value when you connect a load of 1kΩ?
 
  • #3
193
17
Also, they are used when you need to give an input signal to a high impedance load. For example, if you have 5V and need a reference voltage of 3.3V to, say, an OP-AMP, you could use a voltage divider to get those 3.3V.
 

Related Threads on Problem with Voltage Dividers

  • Last Post
Replies
2
Views
6K
  • Last Post
Replies
7
Views
2K
  • Last Post
2
Replies
25
Views
2K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
15
Views
1K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
6
Views
3K
  • Last Post
2
Replies
31
Views
13K
  • Last Post
Replies
13
Views
7K
  • Last Post
Replies
1
Views
5K
Top