MSP430F415 and a custom LCD

Started by ljbdeshler January 19, 2006
We made a custom, 72 segment lcd and it is 1/3 duty, 1/3 bias and 
3.3vdc operating voltage.  The pc board is nothing but 3 buttons, 3.3v 
regulator, MSP430F415 and LCD.  We had the LCD remade because the 
viewing angle (6oclock) looked better at 12oclock than 6.  I had 2 
boards with the new lcd made.  They are identical boards.  One powered 
up and looks great.  The other one turns on lcd segments that should 
not be on.  I am using 120K 1% resistors for the voltage divider 
(R33,R23,R13,R03) and we have .1uf caps on the voltage divider lines.  
No contrast control.  I am getting near my wits end as I cannot find 
what would cause this.  We also see some ghosting of segments that 
should be off but I think this may be in part because the board layout 
guy let lcd traces walk over the top of other lcd traces.  Anyone out 
there with similar experiences?  Thanks in advance.

Beginning Microcontrollers with the MSP430