M34E02-F datasheet(19/36 Pages) STMICROELECTRONICS

19 / 36 page

DocID10367 Rev 14

19/36

M34E02-F

Initial delivery state

The device is delivered with all bits in the memory array set to ‘1’ (each Byte contains FFh).

Use within a DDR1/DDR2/DDR3 DRAM module

In the application, the M34E02-F is soldered directly in the printed circuit module. The three

Chip Enable inputs (E0, E1, E2) must be connected to VSS or VCC directly (that is without

using a pull-up or pull-down resistor) through the DIMM socket (see Table 4). The pull-up

resistors needed for normal behavior of the I2C bus are connected on the I2C bus of the

mother-board (as shown in Figure 11).

The Write Control (WC) of the M34E02-F can be left unconnected. However, connecting it to

VSS is recommended, to maintain full read and write access.

5.1

Programming the M34E02-F

The situations in which the M34E02-F is programmed can be considered under two

headings:

•

when the DDR DRAM is isolated (not inserted on the PCB motherboard)

•

when the DDR DRAM is inserted on the PCB motherboard

5.1.1

Isolated DRAM module

With specific programming equipment, it is possible to define the M34E02-F content, using

Byte and Page Write instructions, and its write-protection using the SWP and CWP

instructions. To issue the SWP and CWP instructions, the DRAM module must be inserted

in a specific slot where the E0 signal can be driven to VHV during the whole instruction. This

programming step is mainly intended for use by DRAM module makers, whose end

application manufacturers will want to clear this write-protection with the CWP on their own

specific programming equipment, to modify the lower 128 Bytes, and finally to set

permanently the write-protection with the PSWP instruction.

Table 4. DRAM DIMM connections

DIMM position

VSS

VCC

VSS

VCC

VSS

VCC

VSS

VCC

VSS

VCC

VSS

VCC

M34E02-F Scheda tecnica(PDF) 19 Page - STMicroelectronics

M34E02-F Scheda tecnica(HTML) 19 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

Scheda tecnica Scarica

Link URL