IS61DDB24M18C
IS61DDB24M18C is 72Mb DDR-II CIO SYNCHRONOUS SRAM manufactured by ISSI.
IS61DDB24M18C IS61DDB22M36C
4Mx18, 2Mx36
72Mb DDR-II (Burst 2) CIO SYNCHRONOUS SRAM
APRIL 2018
Features
- 2Mx36 and 4Mx18 configuration available.
- mon I/O read and write ports.
- Max. 400 MHz clock for high bandwidth
- Synchronous pipeline read with self-timed late write operation.
- Double Data Rate (DDR) interface for read and write input ports.
- Fixed 2-bit burst for read and write operations.
- Clock stop support.
- Two input clocks (K and K#) for address and control registering at rising edges only.
- Two input clocks (C and C#) for data output control.
- Two echo clocks (CQ and CQ#) that are delivered simultaneously with data.
- +1.8V core power supply and 1.5V to 1.8V VDDQ, used with 0.75V to 0.9V VREF.
- HSTL input and output interface.
- On-chip delay-locked loop (DLL) for wide data valid window.
- Full data coherency.
- Boundary scan using limited set of JTAG 1149.1 functions.
- Byte write capability.
- Fine ball grid array (FBGA) package:
13mmx15mm and 15mmx17mm body size 165-ball (11 x 15) array
- Programmable impedance output drivers via 5x user-supplied precision resistor.
DESCRIPTION
The 72Mb IS61DDB22M36C and IS61DDB24M18C are synchronous, high-performance CMOS static random access memory (SRAM) devices. These SRAMs have a mon I/O bus. 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 operations of these DDR-II (Burst of 2) CIO SRAMs. Read and write addresses are registered on alternating rising edges of the K clock. Reads and writes are 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 one cycle after the write address. The first data-in burst is clocked one cycle later than the write mand signal, and the second burst is timed to the following...