DAC888_15 Datasheet, PDF (10/12 Pages) Analog Devices – 8-BIt LevelTriggered Latch

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DAC-888 BYTEDAC<78I -BIT HIGH-SPEED "MICROPROCESSOR COMPATIBLE" MUL TIPL YING orA CONVERTER
BASIC BIPOLAR OUTPUT OPERATION
Both outputs have an extremely wide voltage compliance,
enabling fast direct current-to-voltage conversion through a
resistor tied to ground or other voltage source. Positive
compliance is 18V above V- and is independent of the
positive supply. Negative compliance is given by V- plus
(IREF X 1kH) plus 2.5V.
supplies is possible. However, at least 8V must be applied to
insure turn-on of the internal bias network.
Symmetrical supplies are not required, as the DAC-888 is
quite insensitive to variations in supply voltage.
Power consumption may be calculated as follows:
Pd = (1+) (V+) + (1-1 (V-).
POWER SUPPLIES
TEMPERATURE PERFORMANCE
The DAC-888operates over a wide range of power supply
voltages from a total supply of 9V to 15V.When operating at
supplies of :t5V or less, IREF~ 1mA is recommended. Low
reference current operation decreases power consumption
The nonlinearity and monotonicity specifications of the
DAC-888 are guaranteed to apply over the entire rated
operating temperature range. Full-scale output current drift
is tight, typically:t 10ppm;o C, with zero scale output current
and increases negative compliance, reference amplifier nega-
tive common-mode range, negative logic input range, and
negative logic threshold range; consult the various figures
for guidance. For example, operation at -4.5V with 'REF =
2mA is not recommended because negative output compli-
ance would be reduced to near zero. Operation from lower
and drift essentially negligible compared to 1/2 LSB.
The temperature coefficient of the reference resistor R1O
should match and track that of the output resistor for
minimum overall full-scale drift. Settling times of the DAC-
888 decrease approximately 10% at -550 C; at + 1250 C an
increase of about 15% is typical.
OB _{Z-80 INTERFACE}
S _{DATA BUS}
CLOCK
O _{::x x ADDRESS}
-- ^{L 10}
E ^IREF
DAC-888
=::0 14
'OUT
~ MREO
/
WR GE
13
- lOUT
Z80
==>< ^{"T "p}
WR
""7"i6917
WR
/
E^x DATA
ADDRESS
BUS
MFmi
ADDRESS
DECODER
CE-----.....
'OUT
lOUT
/
x
6502 INTERFACE
6502
"p
R/Vi
DATA BUS
10
IREF
DAC-888
WAGE
16'1' 17
-14
lOUT
--
13 - lOUT
ADDRESS
BUS
82
ADDRESS
DECODER
82
ADDRESS
R/i'J
DATA
IT
'OUT
'OUT
x_"
X
/
xX
"--/
><
11.110
7/89, Rev. B