A basic IC supply question, but help would be much appreciated
Hi,
This is my first post, so I hope it's at least in the correct forum!
I could really do with some help, on a very basic question, as most of my electronics knowledge seems to have escaped me!
I am trying to supply the IC, which is a PAL16R8A (pictured) with 4V and 2mA.
Box 1 shows my first attempt. I used a current limiting resistor to limit the current to 2mA, which it does. However, the voltage drops considerably to 1.2V.
My second attempt, box 2, used a voltage divider (box 3) in a (vain) attempt to negate the resistance of the IC (which I assumed was causing the voltage drop to 1.2V, as without the IC the voltage is 4V (box 3). However, the IC was still only supplied with 1.2V.
If I decrease the 2K5 ohm resistance, the current will increase and the limit for the IC 5mA. So I'm stuck....there's no real help using the google search engine, and the electronics book I've ordered is a few days away yet!
Would anybody be able to give me some advice as to how I may supply the IC with 4V and no more than 5mA. Any help would be really (really) appreciated!
Thanks in advance!
Hi,
This is my first post, so I hope it's at least in the correct forum!
I could really do with some help, on a very basic question, as most of my electronics knowledge seems to have escaped me!
I am trying to supply the IC, which is a PAL16R8A (pictured) with 4V and 2mA.
Box 1 shows my first attempt. I used a current limiting resistor to limit the current to 2mA, which it does. However, the voltage drops considerably to 1.2V.
My second attempt, box 2, used a voltage divider (box 3) in a (vain) attempt to negate the resistance of the IC (which I assumed was causing the voltage drop to 1.2V, as without the IC the voltage is 4V (box 3). However, the IC was still only supplied with 1.2V.
If I decrease the 2K5 ohm resistance, the current will increase and the limit for the IC 5mA. So I'm stuck....there's no real help using the google search engine, and the electronics book I've ordered is a few days away yet!
Would anybody be able to give me some advice as to how I may supply the IC with 4V and no more than 5mA. Any help would be really (really) appreciated!
Thanks in advance!
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