| Density | 4M |
|---|---|
| Org | 256Kx18 |
| Vcc | 3.3V |
| VccQ | 2.5/3.3V |
| Status | Prod |
| Comment | P, ECC feature |
| tKQ(ns) | 2.6, 3.1 |
| Pkg Pins | QFP(100), BGA(119), BGA(165) |
| Speed Mhz | 250, 200 |
The 4Mb product family features high-speed, low- power synchronous static RAMs designed to provide a burstable, high-performance, 'no wait' state, device for networking and communications applications. They are organized as 128K words by 36 bits and 256K words by 18 bits, fabricated with ISSI's advanced CMOS technology. Incorporating a 'no wait' state feature, wait cycles are eliminated when the bus switches from read to write, or write to read. This device integrates a 2-bit burst counter, high-speed SRAM core, and high-drive capability outputs into a single monolithic circuit. All synchronous inputs pass through registers are controlled by a positive-edge-triggered single clock input. Operations may be suspended and all synchronous inputs ignored when Clock Enable, /CKE is HIGH. In this state the internal device will hold their previous values. All Read, Write and Deselect cycles are initiated by the ADV input. When the ADV is HIGH the internal burst counter is incremented. New external addresses can be loaded when ADV is LOW. Write cycles are internally self-timed and are initiated by the rising edge of the clock inputs and when /WE is LOW. Separate byte enables allow individual bytes to be written. A burst mode pin (MODE) defines the order of the burst sequence. When tied HIGH, the interleaved burst sequence is selected. When tied LOW, the linear burst sequence is selected.