MOS INTEGRATED CIRCUIT
µPD44164085, 44164185, 44164365
18M-BIT DDRII SRAM SEPARATE I/O
2-WORD BURST OPERATION
The µPD44164085 is a 2,097,152-word by 8-bit, the µPD44164185 is a 1,048,576-word by 18-bit and the
µPD44164365 is a 524,288-word by 36-bit synchronous double data rate static RAM fabricated with advanced CMOS
technology using full CMOS six-transistor memory cell.
The µPD44164085, µPD44164185 and µPD44164365 integrates unique synchronous peripheral circuitry and a
burst counter. All input registers controlled by an input clock pair (K and /K) are latched on the positive edge of K and
These products are suitable for application which require synchronous operation, high speed, low voltage, high
density and wide bit configuration.
These products are packaged in 165-pin PLASTIC BGA.
• 1.8 ± 0.1 V power supply and HSTL I/O
• DLL circuitry for wide output data valid window and future frequency scaling
• Separate independent read and write data ports
• DDR read or write operation initiated each cycle
• Pipelined double data rate operation
• Separate data input/output bus
• Two-tick burst for low DDR transaction size
• Two input clocks (K and /K) for precise DDR timing at clock rising edges only
• Two output clocks (C and /C) for precise flight time and clock skew matching-clock
and data delivered together to receiving device
• Internally self-timed write control
• Clock-stop capability with µs restart
• User programmable impedance output
• Fast clock cycle time : 4.0 ns (250 MHz), 5.0 ns (200 MHz), 6.0 ns (167 MHz)
• Simple control logic for easy depth expansion
• JTAG boundary scan
The information in this document is subject to change without notice. Before using this document, please
confirm that this is the latest version.
Not all products and/or types are available in every country. Please check with an NEC Electronics
sales representative for availability and additional information.
Document No. M15823EJ7V1DS00 (7th edition)
Date Published July 2004 NS CP(K)
Printed in Japan
The mark shows major revised points.