| Density | 18M |
|---|---|
| Org | 1Mx18 |
| Burst | 2 |
| Status | Prod |
| Speed Mhz | 250, 300, 333 |
| Comments Previous Revision | 2.5 Cycle Read Latency |
| Product Family | 61 = QUAD/P DDR-2/P |
| Configuration | 1M18 = 1M x18 |
| Package Code | B4 = 165 ball BGA (13 x 15 mm) |
| ROHS Version | = Leaded |
| Burst Type | B2 = Burst 2 |
| Die Rev | A = A |
| Read Latency (RL) | blank = 1.5 clock cycles or 2.5 clock cycles |
| ODT Option | 1 = ODT Option 1 If ODT = HIGH or floating, a high range termination resistance is selected. If ODT = LOW, a low range termination resistance is selected. |
| Product Type | QDP = QUADP |
| Temperature Range | I = Industrial (-40°C to +85°C) |
| Speed | 250 = 250MHz |
The 18MB IS61QDPB251236A/A1/A2 and IS61QDPB21M18A/A1/A2 are synchronous, high- performance CMOS static random access memory (SRAM) devices. These SRAMs have separate I/Os, eliminating the need for high-speed bus turnaround. The rising edge of K clock initiates the read/write operation, and all internal operations are self-timed. Refer to the Timing Reference Diagram for Truth Table for a description of the basic operation of these QUADP (Burst of 2) SRAMs. Read and write addresses are registered on alternating rising edges of the K clock. Read and write performed in double data rate. Byte writes can change with the corresponding data-in to enable or disable writes on a per-byte basis. An internal write buffer enables the data-ins to be registered half a cycle earlier than the write address. The first data-in burst is clocked at the same time as the write command signal, and the second burst is timed to the following rising edge of the K# clock. During the burst read operation, the data-outs from the first bursts are updated from output registers of the second rising edge of the K# clock (starting two and half cycles later after read command). The data-outs from the second bursts are updated with the third rising edge of the K clock. The K and K# clocks are used to time the data-outs. The device is operated with a single +1.8V power supply and is compatible with HSTL I/O interface.