This post explains for the semiconductor C271C.
The Part Number is UPC271C.
The function of this semiconductor is Voltage Comparator.
Manufacturer: NEC
Preview images :
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Description
The uPC271, uPC311 are voltage comparators that have input currents more than a hundred times lower than device like conventional standard type of 710. It is also designed to operate over a wide range of supply voltage.
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Features
1. Operate from single 5 V supply
2. Maximum input current : 200 nA
3. Maximum offset current : 50 nA
4. Fast transient response : 200 ns TYP.
5. LM311 Direct Replacement.
