Part Number: LP2951
Dear sir/madam
Now I use LP2951-50DRGR to provide a fixed output of 5V in my system. I found a description in the datasheet that ERROR will go low when Vout drops 6% of its norminal value. I calculate that 5V * 94% equals to 4.7V. It means that when the Vout is below 4.7V, then ERROR PIN will go low. Now I connect a resistor of 33ohm between Vout and GND, then I found that the Vout = 4.4V, but the ERROR does NOT go low, still provide 4.98V. So I will find your help.
I attached the schematic, using png form in the attachment, the circuit works like that, let me explain as below:
when I provide 12V as input, then LP2951 is powered. It will output 5V in the OUTPUT PIN. Now LED4 and LED2 should be lighted. When I press the buttow, a 33-ohm resistor is connected. Now the current is over 100mA. So the Vout should drop. And I measured the output voltage, the value is 4.4V, but ERROR PIN is still as high as 4.98V.
Thanks and looking forward to your reply.
BR,
Joey