DAC0830LCM National Semiconductor, DAC0830LCM Datasheet - Page 17

• Manufacturer Part Number: DAC0830LCM
• Description: 8-Bit P Compatible/ Double-Buffered D to A Converters
• Manufacturer: National Semiconductor

DAC0830 Series Application Hints
2.8 Miscellaneous Application Hints
These converters are CMOS products and reasonable care
should be exercised in handling them to prevent catastrophic
failures due to static discharge.
Conversion accuracy is only as good as the applied refer-
ence voltage so providing a stable source over time and tem-
perature changes is an important factor to consider.
A “good” ground is most desirable. A single point ground dis-
tribution technique for analog signals and supply returns
keeps other devices in a system from affecting the output of
the DACs.
During power-up supply voltage sequencing, the −15V (or
−12V) supply of the op amp may appear first. This will cause
(Continued)
Variation vs. Temperature
Gain and Linearity Error
FIGURE 18.
DS005608-34
17
the output of the op amp to bias near the negative supply po-
tential. No harm is done to the DAC, however, as the on-chip
15 k
from I
drop below ground.
Careful circuit construction with minimization of lead lengths
around the analog circuitry, is a primary concern. Good high
frequency supply decoupling will aid in preventing inadvert-
ant noise from appearing on the analog output.
Overall noise reduction and reference stability is of particular
concern when using the higher accuracy versions, the
DAC0830 and DAC0831, or their advantages are wasted.
3.0 GENERAL APPLICATION IDEAS
The connections for the control pins of the digital input regis-
ters are purposely omitted. Any of the control formats dis-
cussed in Section 1 of the accompanying text will work with
any of the circuits shown. The method used depends on the
overall system provisions and requirements.
The digital input code is referred to as D and represents the
decimal equivalent value of the 8-bit binary input, for ex-
ample:
Pin 13
1
1
0
0
0
MSB
OUT1
1
0
0
0
0
feedback resistor sufficiently limits the current flow
when this lead is internally clamped to one diode
1
0
0
0
0
Binary Input
1
0
1
0
0
1
0
0
0
0
1
0
0
0
0
1
0
0
1
0
Pin 7
LSB
1
0
0
0
0
Equivalent
Decimal
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255
128
16
D
2
0