This part is a kind of semiconductor called TSOP-1738.

Function of this product has Photo Modules for PCM Remote Control Systems.

Manufacturers : Vishay Telefunken

Image and pinout :

Some of the text within the PDF file :

TSOP17.. Vishay Telefunken Photo Modules for PCM Remote Control Systems Available types for different carrier frequencies Type TSOP1730 TSOP1736 TSOP1738 TSOP1756 fo 30 kHz 36 kHz 38 kHz 56 kHz Type TSOP1733 TSOP1737 TSOP1740 fo 33 kHz 36.7 kHz 40 kHz Description The TSOP17.. – series are miniaturized receivers for infrared remote control systems. PIN diode and preamplifier are assembled on lead frame, the epoxy package is designed as IR filter. The demodulated output signal can directly be decoded by a microprocessor. TSOP17.. is the standard IR remote control receiver series, supporting all major transmission codes. GND VS OUT 94 8691 Features D Photo detector and preamplifier in one package D Internal filter for PCM frequency D Improved shielding against electrical field disturbanc [ ... ]

TSOP-1738 PDF Datasheet Download