This post explains for the TTL.
The Part Number is 7447.
The function of this semiconductor is BCD to 7-Segment Decoder / Driver.
The package is DIP 16 Pin Type
Manufacturer: Fairchild Semiconductor
Preview :
Description
The 7447 is BCD to 7-Segment Decoder / Driver.
The DM7446A and DM7447A feature active-LOW outputs designed for driving common-anode LEDs or incandescent indicators directly. All of the circuits have full ripple-blanking input/output controls and a lamp test input. Segment identification and resultant displays are shown on a following page. Display patterns for BCD input counts above nine are unique symbols to authenticate input conditions. All of the circuits incorporate automatic leading and/or trailing-edge, zero-blanking control (RBI and RBO). Lamp test (LT) of these devices may be performed at any time when the BI/RBO node is at a HIGH logic level.
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Features
1. Open-Collector Outputs Drive Indicators Directly
2. Lamp-Test Provision
3. Leading / Trailing Zero Suppression
Other data sheets are available within the file: DM7446AN, DM7447AN, SN7446A, SN74LS46
7447 PDF Datasheet
