Intel 80C196KB Series, Руководство пользователя, Страница: 63 / 98

80C196KB USER’S GUIDE
CROSSTALK ÐSee ‘‘Off-Isolation’’.
D.C. INPUT LEAKAGE ÐLeakage current to ground
from an analog input pin.
DIFFERENTIAL NON-LINEARITY ÐThe differ-
ence between the ideal and actual code widths of the
terminal based characteristic of a converter.
FEEDTHROUGH ÐAttenuation of a voltage applied
on the selected channel of the A/D converter after the
sample window closes.
FULL SCALE ERROR ÐThe difference between the
expected and actual input voltage corresponding to the
full scale code transition.
IDEAL CHARACTERISTIC ÐA characteristic with
its first code transition at V
IN
e
0.5 LSB, its last code
transition at V
IN
e
(V
REF
b
1.5 LSB) and all code
widths equal to one LSB.
INPUT RESISTANCE ÐThe effective series resistance
from the analog input pin to the sample capacitor.
LSBÐLEAST SIGNIFICANT BIT : The voltage value
corresponding to the full scale voltage divided by 2
n
,
where n is the number of bits of resolution of the con-
verter. For a 10-bit converter with a reference voltage
of 5.12 volts, one LSB is 5.0 mV. Note that this is
different than digital LSBs, since an uncertainty of two
LSBs, when referring to an A/D converter, equals
10 mV. (This has been confused with an uncertainty of
two digital bits, which would mean four counts, or
20 mV.)
MONOTONIC ÐThe property of successive approxi-
mation converters which guarantees that increasing in-
put voltages produce adjacent codes of increasing value,
and that decreasing input voltages produce adjacent
codes of decreasing value.
NO MISSED CODES ÐFor each and every output
code, there exists a unique input voltage range which
produces that code only.
NON-LINEARITY ÐThe maximum deviation of code
transitions of the terminal based characteristic from the
corresponding code transitions of the ideal characteris-
tics.
OFF-ISOLATION ÐAttenuation of a voltage applied
on a deselected channel of the A/D converter. (Also
referred to as Crosstalk.)
REPEATABILITY ÐThe difference between corre-
sponding code transitions from different actual charac-
teristics taken from the same converter on the same
channel at the same temperature, voltage and frequency
conditions.
RESOLUTION
ÐThe number of input voltage levels
that the converter can unambiguously distinguish be-
tween. Also defines the number of useful bits of infor-
mation which the converter can return.
SAMPLE DELAY ÐThe delay from receiving the start
conversion signal to when the sample window opens.
SAMPLE DELAY UNCERTAINTY ÐThe variation
in the Sample Delay.
SAMPLE TIME ÐThe time that the sample window is
open.
SAMPLE TIME UNCERTAINTY ÐThe variation in
the sample time.
SAMPLE WINDOW ÐBegins when the sample capac-
itor is attached to a selected channel and ends when the
sample capacitor is disconnected from the selected
channel.
SUCCESSIVE APPROXIMATION ÐAn A/D con-
version method which uses a binary search to arrive at
the best digital representation of an analog input.
TEMPERATURE COEFFICIENTS ÐChange in the
stated variable per degree centigrade temperature
change. Temperature coefficients are added to the typi-
cal values of a specification to see the effect of tempera-
ture drift.
TERMINAL BASED CHARACTERISTIC ÐAn Ac-
tual Characteristic which has been rotated and translat-
ed to remove zero offset and full-scale error.
V
CC
REJECTION ÐAttenuation of noise on the V
CC
line to the A/D converter.
ZERO OFFSET ÐThe difference between the expected
and actual input voltage corresponding to the first code
transition.
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