NOTE: The SN54147, SN54LS147, SN54148, SN74147, SN74LS147, and SN74148 are obsolete and are no longer supplied.
These TTL encoders feature priority decoding of the inputs to ensure that only the highest-order data line is encoded. The '147 and 'LS147 encode nine data lines to four-line (8-4-2-1) BCD. The implied decimal zero condition requires no input condition as zero is encoded when all nine data lines are at a high logic level. The '148 and 'LS148 encode eight data lines to three-line (4-2-1) binary (octal). Cascading circuitry (enable input E1 and enable output E0) has been provided to allow octal expansion without the need for external circuitry. For all types, data inputs and outputs are active at the low logic level. All inputs are buffered to represent one normalized Series 54/74 or 54LS/74LS load, respectively.
| Type | Title | Date | ||
|---|---|---|---|---|
| * | Data sheet | SN54147, SN54148, SN54LS147, SN54LS148,SN74147, SN74148 (TIM9907), SN74LS147, SN datasheet (Rev. B) | 26 May 2004 | |
| * | SMD | SN54LS148 SMD 78027012A | 21 Jun 2016 | |
| Selection guide | Logic Guide (Rev. AB) | 12 Jun 2017 | ||
| Application note | Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) | 02 Dec 2015 | ||
| User guide | LOGIC Pocket Data Book (Rev. B) | 16 Jan 2007 | ||
| Application note | Semiconductor Packing Material Electrostatic Discharge (ESD) Protection | 08 Jul 2004 | ||
| Application note | TI IBIS File Creation, Validation, and Distribution Processes | 29 Aug 2002 | ||
| Application note | Designing With Logic (Rev. C) | 01 Jun 1997 | ||
| Application note | Designing with the SN54/74LS123 (Rev. A) | 01 Mar 1997 | ||
| Application note | Input and Output Characteristics of Digital Integrated Circuits | 01 Oct 1996 | ||
| Application note | Live Insertion | 01 Oct 1996 |
For additional terms or required resources, click any title below to view the detail page where available.
| Package | Pins | CAD symbols, footprints & 3D models |
|---|---|---|
| CDIP (J) | 16 | Ultra Librarian |
| CFP (W) | 16 | Ultra Librarian |
| LCCC (FK) | 20 | Ultra Librarian |
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