This part is a kind of semiconductor called DS1302.

Function of this product has Trickle-Charge Timekeeping Chip.

Manufacturers : Maxim Integrated

Image and pinout :

Some of the text within the PDF file :

DS1302 Trickle-Charge Timekeeping Chip BENEFITS AND FEATURES  Completely Manages All Timekeeping Functions o Real-Time Clock Counts Seconds, Minutes, Hours, Date of the Month, Month, Day of the Week, and Year with Leap-Year Compensation Valid Up to 2100 o 31 x 8 Battery-Backed General-Purpose RAM  Simple Serial Port Interfaces to Most Microcontrollers o Simple 3-Wire Interface o TTL-Compatible (VCC = 5V) o Single-Byte or Multiple-Byte (Burst Mode) Data Transfer for Read or Write of Clock or RAM Data  Low Power Operation Extends Battery Backup Run Time o 2.0V to 5.5V Full Operation o Uses Less Than 300nA at 2.0V  8-Pin DIP and 8-Pin SO Minimizes Required Space  Optional Industrial Temperature Range: -40°C to +85°C Supports Operation in a Wide Range of Applications  Unde [ ... ]

DS1302 PDF Datasheet Download