ARM Technical Support Knowledge Articles

Are there any design changes in lead free boards?

Applies to: Development Boards

Answer

[Updated 22 May 2007]

We are updating our development boards to conform to the European Union Restriction of Hazardous Substances (RoHS) directive known as 'lead free'.

This FAQ details changes that have been made to our development boards during the lead free transition.  Only details of boards that we have released to production are shown, this is to ensure that all relevant functional changes have been checked.  This FAQ will be updated as boards are released.  The Integrator range of boards are not being transitioned to lead free, as these are now obsolete products.  The IM-LT1 and IM-LT3 interface modules will be produced in lead free versions.

Lead free boards can easily be recognized by the 'PB-free' symbol PB_free_symbol on the board's silk screen, board revision details are also given below.

In the information below, minor details that do not have any significant effect on functionality have been omitted for clarity.  For example, minor changes to PCB footprints, changing obsolete parts with functional equivalents and tidying schematic diagrams.  There are more complete lists of changes on the last page of lead free schematic diagrams, the details below are the changes that have been considered notable.

Core Tile CT926 / CT1136

Leaded board number HBI-0131A, lead free board number HBI-0131B.

The test chip clock outputs HCLKEXT[4:0] have had a 33R series resistor added to improve signal quality.

Core Tile CT11MPCore

Leaded board number HBI-0146C, lead free board number HBI-0146D.

No functional changes.

Logic Tile LT-XC2V6000/8000

Leaded board number HBI-0102C, lead free board number HBI-0102D.

No functional changes.

IM-LT1

Leaded board number HBI-0106C, lead free board number HBI-0106D.

This board has had a net (track) added to allow easier stacking of boards when there is no motherboard present.  As this board was not originally designed for 'no motherboard stacking', a wire modification was required to allow a clock connection from a Logic Tile mounted on this board to a Core Module below.  The lead free version has PCB pads where a 0R 0603 surface mount resistor can be added to complete this clock connection.  This information is covered in more detail in Application Note 101.

Summary: Functionality of the board not changed; it is now easier to make the required clock modification if stacking boards without a motherboard.

Emulation Baseboard (EB)

Leaded board number HBI-0140C, lead free board number HBI-0140D.

  • The 64MB Disk on Chip (DoC) has been replaced with an additional 64MB of NOR flash. Due to this, rev D requires bootmonitor version 4.0 or later.
  • The audio CODEC (U4) has been upgraded to a rev B part.  This has slightly better audio performance.
  • The Ethernet IC has been changed from LAN91C111 to LAN9118.  This has a simpler interface and is more efficient with the EB's memory controller.
  • The reserved signals to the PISMO connector (J35) have been renamed to be in-line with the specification.  No change to netlist.

Summary:  The main changes are the removal of DoC and the new Ethernet IC.

IM-LT3

Leaded board number HBI-0139A, lead free board number HBI-0139B.

  • A Schmitt device has been added in the push button circuit to prevent debouncing problems.
  • The configuration link J14 changed to a switch, to avoid losing links.
  • J7 pins 33 (nPPRES0) and 34 (GND) were reversed in rev A, now fixed. This means that in rev A boards the presence of the module was not controllable, it was always seen as present by motherboards.
  • Additional decoupling capacitors added to the power supply input.
  • Capacitor C15 changed to a low ESR AVX part.

Summary: Minor functionality of the board changed, cleaner push button signal input into the FPGA.


Platform Baseboard (PB926EJ-S)

Leaded board number HBI-0117C, lead free board number HBI-0117E.

  • The 64MB Disk on Chip (DoC) has been replaced with an additional 64MB of NOR flash.
  • The audio CODEC (U4) has been upgraded to a rev B part.  This has slightly better audio performance.
  • The PISMO interface has been updated to match the 1.0 specification.
  • A problem has been fixed where the D_RTCK signal was not being isolated from TCK when the board was in configuration mode.  This previously affected loading FPGA images for Application Note 125, and could also cause signal integrity problems when using several stacked Logic Tiles.
  • The configuration link J32 changed to a switch, to avoid losing links.
  • The PCI interrupt ordering has been corrected:

 PCI pin  rev C (incorrect)  rev D (fixed)
 A6 P_nINTD P_nINTA
 B7 P_nINTA P_nINTB
 A7 P_nINTB P_nINTC
 B8 P_nINTC P_nINTD








Summary:  Several fixes and removal of DoC.


PCI Backplane

Leaded board number HBI-0122C, lead free board number HBI-0122D.

  • The power supply has been changed to a more efficient model.

No functional changes.


AT1

Leaded board number HBI-0114B, lead free board number HBI-0114C.

  • Resistors R58 - R60 are now DO NOT FIT.  These are on the outputs of the spare clock buffer U4-2, the change will only affect customers who have modified boards to use this.


CT7TDMI

Leaded board number HBI-0141B, lead free board number HBI-0141C.

No functional changes.

Application Baseboard (AB926EJ-S)

Leaded board number HBI-0118B, lead free board number HBI-0118C.

  • The 64MB Disk on Chip (DoC) has been replaced with an additional 64MB of NOR flash.
  • The audio CODEC (U4) has been upgraded to a rev B part.  This has slightly better audio performance.
  • The configuration link J32 changed to a switch, to avoid losing links.
  • The previously unconnected signals SSPFSSOUT, nSSPCTLOE, nSSPOE from the SSP in the development chip are now routed to test points.
  • The JTAG connector has been moved slightly to allow the RVI LVDS probe to be used.

Summary:  The main change is the removal of the DoC.

Interface Tile 1 (IT1)

Leaded board number HBI-0128A, lead free board number HBI-0128B

No functional changes.

Attachments: img14465.gif

Article last edited on: 2009-01-20 10:54:07

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