UT52L1616

The UT52L1616 is a high-speed CMOS dynamic random-access memory containing 16,777,216 bits. It is internally configured as a dual memory array (512K x 16) with a synchronous interface (all signals are registered on the positive edge of the clock signal, CLK). Each of the two internal banks is organized with 2,048 rows and with either 256 columns by 16 bits.

Read and write accesses to the SDRAM are burst oriented; accesses start at a selected location and continue for a programmed number of locations in a programmed sequence. Accesses begin with the registration of an ACTIVATE command which will then be followed by a READ or WRITE command. The address bits registered coincident with the ACTIVATE command are used to select the bank and row to be accessed (A11 selects the bank, A0-10 selects the row). The address bits coincident with the READ or WRITE command are used to select the starting column location for the burst access.

The UT52L1616 uses an internal pipelined architecture to achieve high-speed operation. This architecture is compatible with the 2n rule of prefetch architectures, but it also allows the column address to be changed on every clock cycle to achieve a high speed, fully random access. Precharging one bank while accessing the alternate bank will hide the precharge cycles and provides seamless high-speed random access operation. The UT52L1616 is designed to comply with the Intel PC (66MHz) and Intel PC/100 (100MHz) specifications.

The UT52L1616 is designed to operate in 3.3V, low-power memory systems. An AUTO REFRESH mode is provided along with a power saving Power-Down mode. All inputs and outputs are LVTTL-compatible.

SDRAMs offer substantial advances in DRAM operating performance, including the ability to synchronously burst data at a high data rate with automatic column-address generation, the ability to interleave between internal banks in order to hide precharge time, and the capability to randomly change column addresses on each clock cycle during a burst access.