MT42C4256 Datasheet | Austin Semiconductor

Austin Semiconductor, Inc. 256K X 4 VRAM 256K x 4 DRAM with 512K x 4 SAM AVAILABLE AS MILITARY SPECIFICATIONS - SMD 5962-89497 - MIL-STD-883 SMJ44C251B MT42C4256 PIN ASSIGNMENT (Top View) VRAM 28-Pin DIP (C) (400 MIL) SC SDQ1 SDQ2 TR/OE DQ1 DQ2 ME/WE NC RAS A8 A6 A5 A4 Vcc 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 Vss SDQ4 SDQ3 SE DQ4 DQ3 DSF CAS QSF A0 A1 A2 A3 A7 28-Pin SOJ (DCJ) 28-Pin LCC (EC) SC SDQ1 SDQ2 TR/OE DQ1 DQ2 ME/WE NC RAS A8 A6 A5 A4 Vcc 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 Vss SDQ4 SDQ3 SE DQ4 DQ3 DSF CAS QSF A0 A1 A2 A3 A7 Features - Class B High-Reliability Processing - DRAM: 262144 Words × 4 Bits SAM: 512 Words × 4 Bits - Single 5-V Power Supply (±10% Tolerance) - Dual Port Accessibility- Simultaneous and Asynchronous Access From the DRAM and SAM Ports - Bidirectional-Data-Transfer Function Between the DRAM and the Serial-Data Register - 4 × 4 Block-Write Feature for Fast Area Fill Operations; As Many as Four Memory Address Locations Written per Cycle From an On-Chip Color Register - Write-Per-Bit Feature for Selective Write to Each RAM I/O; Two Write-Per-Bit Modes to Simplify System Design - Enhanced Page-Mode Operation for Faster Access - CAS-Before-RAS (CBR) and Hidden Refresh Modes - All Inputs/Outputs and Clocks Are TTL patible - Long Refresh Period: Every 8 ms (Max) - Up to 33-MHz Uninterrupted Serial-Data Streams - 3-State Serial I/Os Allow Easy Multiplexing of Video-Data Streams - 512 Selectable Serial-Register Starting - Split Serial-Data Register for Simplified Real-Time Register Reload 28-Pin ZIP (CZ) DSF DQ3 SDQ2 Vss SDQ0 TRG DQ1 GND A8 A5 Vcc A3 A1 QSF 1 3 5 7 9 11 13 15 17 19 21 23 25 27 2 4 6 8 10 12 14 16 18 20 22 24 26 28 DQ2 SE SDQ3 SC SDQ1 DQ0 W RAS A8 A4 A7 A2 A0...