This part is a kind of semiconductor called AD636.

Function of this product has Low Level/ True RMS-to-DC Converter.

Manufacturers : Analog Devices

Image and pinout :

Some of the text within the PDF file :

a FEATURES True RMS-to-DC Conversion 200 mV Full Scale Laser-Trimmed to High Accuracy 0.5% Max Error (AD636K) 1.0% Max Error (AD636J) Wide Response Capability: Computes RMS of AC and DC Signals 1 MHz –3 dB Bandwidth: V RMS >100 mV Signal Crest Factor of 6 for 0.5% Error dB Output with 50 dB Range Low Power: 800 ␮ A Quiescent Current Single or Dual Supply Operation Monolithic Integrated Circuit Low Cost Available in Chip Form PRODUCT DESCRIPTION VIN 1 NC 2 –VS 3 CAV 4 dB 5 BUF OUT 6 BUF IN 7 Low Level, True RMS-to-DC Converter AD636 PIN CONNECTIONS & FUNCTIONAL BLOCK DIAGRAM IOUT ABSOLUTE VALUE 14 +VS 13 NC RL 10k⍀ + CURRENT MIRROR BUF IN – AD636 SQUARER DIVIDER COMMON 12 NC 11 NC AD636 BUF BUF OUT 10k⍀ CURRENT MIRROR + BUF – 10k⍀ 10k⍀ 10 COMMON 9 8 +VS SQUARE [ ... ]

AD636 PDF Datasheet Download