74LS670 Datasheet | Motorola Semiconductor

SN54/74LS670 4 x 4 REGISTER FILE WITH 3-STATE OUTPUTS The TTL / MSI SN54 / 74LS670 is a high-speed, low-power 4 x 4 Register File organized as four words by four bits. Separate read and write inputs, both address and enable, allow simultaneous read and write operation. The 3-state outputs make it possible to connect up to 128 outputs to increase the word capacity up to 512 words. Any number of these devices can be operated in parallel to generate an n-bit length. The SN54 / 74LS170 provides a similar function to this device but it Features open-collector outputs. 4 x 4 REGISTER FILE WITH 3-STATE OUTPUTS LOW POWER SCHOTTKY - - - - - Simultaneous Read/ Write Operation Expandable to 512 Words by n-Bits Typical Access Time to 20 ns 3-State Outputs for Expansion Typical Power Dissipation of 125 m W J SUFFIX CERAMIC CASE 620-09 16 1 CONNECTION DIAGRAM DIP (TOP VIEW) VCC 16 D1 15 WA 14 WB 13 EW 12 ER 11 Q1 10 Q2 9 NOTE: The Flatpak version has the same pinouts (Connection Diagram) as the Dual In-Line Package. 16 1 N SUFFIX PLASTIC CASE 648-08 16 1 D SUFFIX SOIC CASE 751B-03 1 D2 2 D3 3 D4 4 RB 5 RA 6 Q4 7 Q3 8 GND ORDERING INFORMATION PIN NAMES LOADING (Note a) HIGH D1 - D4 WA, WB EW RA, RB ER Q1 - Q4 Data Inputs Write Address Inputs Write Enable (Active LOW) Input Read Address Inputs Read Enable (Active LOW) Input Outputs (Note b) 0.5 U.L. 0.5 U.L. 1.0 U.L. 0.5 U.L. 1.5 U.L. 65 (25) U.L. LOW 0.25 U.L. 0.25 U.L. 0.5 U.L. 0.25 U.L. 0.75 U.L. 15 (7.5) U.L. SN54LSXXXJ SN74LSXXXN SN74LSXXXD Ceramic Plastic SOIC LOGIC SYMBOL 12 14 13 5 4 WA EW WB RA RB E R 11 15 1 2 3 NOTES: a) 1 TTL Unit Load (U.L.) = 40 µA HIGH/1.6 m A LOW. b) The Output LOW drive factor is 7.5 U.L. for Military (54) and 15 U.L. for mercial (74) Temperature Ranges. The Output HIGH drive factor is 25 U.L. for Military and 65 U.L. for mercial Temperature...