Errata: EDB9312

4/14/04
Errata: EDB9312
This errata contains the full text and drawings for two Engineering Change Notices (ECN) from
Videon. These are Videon ECN # CM-0306-24 and CM-0403-05. Both ECNs describe modifications needed on the EDB9312 circuit board. These ECNs provide all details needed to update
existing boards to the new modification level.
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(All Rights Reserved)
ER515DB1
MAR‘04
1
ECN No.
Engineering Change Notice
CM-0306-24
Sheet 1 of 3
Reason for Change:
New Release
(Engr.)
Facilitate Production/Inspection
Customer Directed
Design Error
Product Upgrade (no errors)
Marketing Directed
Drafting Error
Schedule Improvement
Vendor Requested
Cost Improvement
Other - Explain:
Class of Change: (Engr.)
Priority:
(Engr.)
PR/ECR # ________________
Top Level Item Affected: (Ex. HDTV PCI) (Engr.)
Standard
II - Interchangeable
Urgent
III - Documentation Only
CIRRUS EDB9312 BOARD
Brief Description of Problem: (Engr.)
The 1.8v power supply sags/dips to an unacceptable voltage level under heavy processor load. The fuse and board layout account for a large enough
voltage drop such that the minimum voltage requirements of the EP9312 are not met.
Description of Change:
(Engr.)
Recommended Solution- Replace the 1.8V regulator with an adjustable one to achieve 1.9V output. Use a sense wire from this voltage regulator’s ADJ
pin to sense the voltage at the load (i.e. the EP9312 device).
Change required to solve the problem:
Remove 1.8V regulator VR2 from the board and also remove the heatsink from this regulator.
Replace this regulator with an adjustable one Part # LT1764AET and install the heatsink on this device.
Remove R384, R385 on the component side near the 1.8V regulator (VR2) and install a 2.4K ohm 0603 1% resistor at R385. Leave R384 unpopulated.
Install a 1.4K ohm 1206 1% resistor to the regulator pin 5 on the bottomside.
Remove C20 and C38 on the bottom side near the EP9312 device and replace with 100uF TC tantalum caps (Vishay Part # 595D107X9010C2T) or
equivalent.
Add 2 additional caps (100uF TC as above) between JP2-p2 and JP105-p26
Attach a wire (22 AWG) on bottomside of board from JP2-p1 to the other end of the 1.4K resistor placed on pin 5 of the new regulator and glue in place.
Mark change on board at assembly revision block making the new rev 2A.
These changes are illustrated on page 2(bottom view) and page 3 (top view).
Items Affected
(Engr.)
Product Spec
Schematics
Y
N
Attachments (Engr.)
Marked Document(s)
Charge Numbers (PM)
Marked Draw ing(s)
Assembly Dwg.
Test Spec
BOM
Engineering:
PR/ECR
Manufacturing:
Other:
Materials & Services:
Software
Manuals
Spare Parts
Management Authorizations:
Tooling
2
Engineering: Paul Brown
Date:
Manufacturing: CR Bargo
Date:
Quality:
Date:
Purchasing:
Date:
Marketing/Programs:
Date:
ER515DB1
ECN No.
Engineering Change Notice
CM-0306-24
Bottomside view:
ER515DB1
3
ECN No.
Engineering Change Notice
CM-0306-24
Topside view:
4
ER515DB1
ECN No.
Engineering Change Notice
CM-0403-05
Sheet 1 of 2
Reason for Change:
New Release
(Engr.)
Facilitate Production/Inspection
Customer Directed
Design Error
Product Upgrade (no errors)
Marketing Directed
Drafting Error
Schedule Improvement
Vendor Requested
Cost Improvement
Other - Explain:
Priority: (Engr.)
Class of Change: (Engr.)
PR/ECR # ________________
Top Level Item Affected: (Ex. HDTV PCI) (Engr.)
Standard
II - Interchangeable
Urgent
III - Documentation Only
CIRRUS EDB9312 BOARD
Brief Description of Problem: (Engr.)
The SDCLK signal going to buffer U7 needs to be cut. The cut improves the quality of the clock signal going to the SDRAM devices. One side affect is
that the SDCLK will no longer be available on the Mictor connectors.
Description of Change: (Engr.)
Refer to the drawing provided in this ECN. Use a sharp Exacto knife and cut the trace indicated.
These changes are illustrated on page 2 (top view).
Items Affected
(Engr.)
Product Spec
Schematics
Y
N
Attachments (Engr.)
Marked Document(s)
Marked Draw ing(s)
Assembly Dwg.
Test Spec
BOM
PR/ECR
Other:
Software
Manuals
Spare Parts
Tooling
Charge Numbers (PM)
Engineering:
Manufacturing:
Materials & Services:
Management Authorizations:
ER515DB1
Engineering: Paul Brown /Signature on FIle
Date: March 5, 2004
Manufacturing: CR Bargo /Signature on FIle
Date: March 5, 2004
Quality:
Date:
Purchasing:
Date:
Marketing/Programs:
Date:
5
ECN No.
Engineering Change Notice
6
CM-0403-05
ER515DB1