PAL16L8                                              PAL DESIGN SPECIFICATION
P7029                                                   BIRKNER/COLI 07/29/81
8-BIT D/A CONVERTER
MMI SUNNYVALE, CALIFORNIA
 NC D0 D1 D2 D3 D4 D5 D6 D7 GND
/OC A7 A6 A5 A4 A3 A2 A1 A0 VCC


IF (D0*OC)  /A0 = D0   ;CONVERT D0 TO ANALOG (LSB)

IF (D1*OC)  /A1 = D1   ;CONVERT D1 TO ANALOG

IF (D2*OC)  /A2 = D2   ;CONVERT D2 TO ANALOG

IF (D3*OC)  /A3 = D3   ;CONVERT D3 TO ANALOG

IF (D4*OC)  /A4 = D4   ;CONVERT D4 TO ANALOG

IF (D5*OC)  /A5 = D5   ;CONVERT D5 TO ANALOG

IF (D6*OC)  /A6 = D6   ;CONVERT D6 TO ANALOG

IF (D7*OC)  /A7 = D7   ;CONVERT D7 TO ANALOG (MSB)


FUNCTION TABLE

/OC D7 D6 D5 D4 D3 D2 D1 D0 A7 A6 A5 A4 A3 A2 A1 A0

;/  DIGITAL IN   ANALOG OUT
;O   DDDDDDDD     AAAAAAAA     COMMENTS
;C   76543210     76543210     FRACTION OF Vmax
-----------------------------------------------
 L   LLLLLLLL     ZZZZZZZZ     V=0
 L   LLLLLLLH     ZZZZZZZL     V=1/256
 L   LLLLLLHL     ZZZZZZLZ     V=1/128
 L   LLLLLLHH     ZZZZZZLL     V=3/256
 L   LLLLLHLL     ZZZZZLZZ     V=1/64
 L   LLLLLHHH     ZZZZZLLL     V=7/256
 L   LLLLHLLL     ZZZZLZZZ     V=1/32
 L   LLLLHHHH     ZZZZLLLL     V=15/256
 L   LLLHLLLL     ZZZLZZZZ     V=1/16
 L   LLLHHHHH     ZZZLLLLL     V=31/256
 L   LLHLLLLL     ZZLZZZZZ     V=1/8
 L   LLHHHHHH     ZZLLLLLL     V=63/256
 L   LHLLLLLL     ZLZZZZZZ     V=1/4
 L   LHHHHHHH     ZLLLLLLL     V=127/256
 L   HLLLLLLL     LZZZZZZZ     V=1/2
 L   HLLLLLHH     LZZZZZLL     V=129/256
 L   HLLLHHHH     LZZZLLLL     V=141/256
 L   HLHHHHHH     LZLLLLLL     V=189/256
 L   HHHHHHHH     LLLLLLLL     V=255/256
 H   XXXXXXXX     ZZZZZZZZ     TEST HI-Z
-----------------------------------------------


DESCRIPTION

THIS PAL PERFORMS THE LOGIC NEEDED TO CONVERT AN 8-BIT DIGITAL SIGNAL INTO
A 256 INCREMENT ANALOG SIGNAL.

OUTPUTS ARE EITHER LOW OR HI-Z WHICH ALLOWS THE CONDITIONAL THREE-STATE
OUTPUTS TO PERFORM THE OPEN COLLECTOR FUNCTION THAT IS NEEDED TO
DRIVE THE RESISTOR NETWORK.