LP340/340B/350 Service Manual
75
Updating the DMD Bias Setting
When Texas Instruments produces Digital Micromirror Devices (DMDs), the chips are sorted into four
different groups, depending on which bias setting provides the best performance.
When the LP350
, LP340 and LP340B
are built, the output of the control signal from the controller ECA is
adjusted to match the optimum bias setting of the particular DMD in the projector’s optical engine.
When you install a new controller ECA or a new optical engine, you must check the bias setting for the
DMD and adjust the setting on the controller ECA if necessary. Operating the LP350
, LP340 or LP340B
with the wrong bias setting degrades the image quality and can shorten the life of the DMD.
NOTE
The projector must be partially disassembled to check the bias setting on the DMD label. See
Removing and Replacing the Controller ECA on page 40 for disassembly instructions.
You change the DMD bias setting on the controller with a Serial Interface Utility. You download the utility
at the InFocus web site.
To check and adjust the DMD setting, you need the following items:
♦
An IBM-compatible PC or laptop
♦
The Serial Utility
♦
A CableWizard II
♦
A serial download cable (210-0087-xx)
Below are the steps you follow when you update the DMD bias setting. The steps need to be followed in
order.
♦
Check the DMD bias setting on the DMD label (page 76)
♦
Get the Serial Utility at the software download page (page 77)
♦
Install the Serial Utility in the computer (page 79)
♦
Connect the projector and the computer (page 80)
♦
Check and adjust the bias setting on the controller ECA (page 81)