This post explains for the semiconductor C1237HA.
The Full Part Number is UPC1237HA. The package is 8 pin slim sip.
The function of this semiconductor is protector IC.
The manufacturers of this product is NEC.
See the preview image and the PDF file for more information.
Preview images :
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Description :
UPC1237 is a monolithic integrated circuit designed for protecting stereo power amplifiers and loudspeakers.
Features
1. Work stably within a wide power supply voltage range. ( Vcc = 25 to 60 V )
2. Both positive and negative output offset can be detected through the same pin.
3. Need only single power supply.
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