User`s guide

LPC3250 Developer’s Kit - User’s Guide

Page 16

Figure 1 – LPC3152 OEM Board Mechanical Dimensions

The SODIMM-200 format is a standard and there are many connectors that are suitable from many

different manufactures. The many sources also keep the connector cost very low. Note that the

connector should be 1.8V keyed.

One suitable connector is 0-1473005-4 from Tyco/AMP. Basically any SODIMM, DDR2, 200pos, 1.8V,

right-angled connector will do.

3.4 Things to note about the LPC3250 OEM Board

3.4.1 LPC3250 Adjustable Core Voltage

The core voltage for the LPC3250 is adjustable via I2C commands sent to the LTC3447 voltage

converter. The core voltage should always be increased to 1.35 volt in order for external mobile DDR

SDRAM to function properly. Initialization code that increase the adjustable core voltage to 1.35V can

be downloaded from Embedded Artists support pages.

Note that it is the user’s responsibility not to program the LTC3447 to generate too high core

voltage, which is possible. The LTC3447 can generate voltages up to 2V, which by far exceed the

limits for the LPC3250.

3.4.2 NAND FLASH Bad Block

The NAND Flash is the K9F1G08U0A from Samsung and has 1 GBit capacity. The chip may include

invalid blocks when shipped from factory. A maximum of 20 invalid blocks may exist initially, i.e., 1004-

1024 valid blocks. Additional invalid blocks may develop while being used. Invalid blocks are defined

as blocks that contain one or more bad bits. Do not erase or program factory-marked bad blocks. More

information about appropriate management of invalid blocks can be found in technical notes and

datasheet from Samsung.

3.4.3 Brand of Memory Chips

Note that there is no guarantee for a certain brand or version of memory chips; SPI-NOR flash, parallel

NAND flash and mobile DDR SDRAM. The lifetime of memory chips is limited and availability can also

be limited from time to time. Embedded Artists make every effort to mount the original design chip on

the board. In case that is impossible a compatible chip will instead be mounted without any prior

notice. There can be small programming differences between mounted brands. The application

66 mm

48 mm

1.8V keying of SODIMM board