moraino
Enlightened
I don't know how to name this thread but here is my story.
I am experimenting the World Torch circuit tonight and found something interesting. Here is the circuit:
http://www.worldtorch.com/LDO-regulator-schematic.php
I first wire up the LM334 according to this data sheet from STMicroelectronics:
http://www.st.com/stonline/products/literature/ds/2157/lm134.htm
The result of led current was a big surprise to me, 52mA instead of 1.5mA using 47 ohm resistor according to World Torch website. I was puzzled, what did I do wrong? I check the wiring and all is fine.
Then I notice on the National datasheet and on the Workd Torch schematics diagram the LM 334 V+ is on the left while STMicro is on the right.
So I reverse the V+ and V- of the LM334 on the bread board and get 0.15mA just like the schematic.
Now the question is since I can reverse V+ and V- on the LM334 and both works, I am wondering which way is the right way? Does STMicro have the wrong data sheet? The reference voltage on the World Torch is 0.065. With the reverse V+ and V- it is about 2.7...I don't understand.
I didn't measure the effeciency of the two but I will do it later to find out the difference...hmmmmm..
Henry
I am experimenting the World Torch circuit tonight and found something interesting. Here is the circuit:
http://www.worldtorch.com/LDO-regulator-schematic.php
I first wire up the LM334 according to this data sheet from STMicroelectronics:
http://www.st.com/stonline/products/literature/ds/2157/lm134.htm
The result of led current was a big surprise to me, 52mA instead of 1.5mA using 47 ohm resistor according to World Torch website. I was puzzled, what did I do wrong? I check the wiring and all is fine.
Then I notice on the National datasheet and on the Workd Torch schematics diagram the LM 334 V+ is on the left while STMicro is on the right.
So I reverse the V+ and V- of the LM334 on the bread board and get 0.15mA just like the schematic.
Now the question is since I can reverse V+ and V- on the LM334 and both works, I am wondering which way is the right way? Does STMicro have the wrong data sheet? The reference voltage on the World Torch is 0.065. With the reverse V+ and V- it is about 2.7...I don't understand.
I didn't measure the effeciency of the two but I will do it later to find out the difference...hmmmmm..
Henry
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