Datasheet

DAC08
Rev. C | Page 15 of 20
RC damping of the output is difficult to prevent while main-
taining adequate sensitivity. However, the major carry from
01111111 to 10000000 provides an accurate indicator of settling
time. This code change does not require the normal 6.2 time
constants to settle to within ±0.2% of the final value, and thus
settling time is observed at lower values of I
REF
.
DAC08 switching transients or “glitches” are very low and can
be further reduced by small capacitive loads at the output at a
minor sacrifice in settling time. Fastest operation can be
obtained by using short leads, minimizing output capacitance
and load resistor values, and by adequate bypassing at the
supply, reference, and V
LC
terminals. Supplies do not require
large electrolytic bypass capacitors because the supply current
drain is independent of input logic states; 0.1 µF capacitors at
the supply pins provide full transient protection.
00268-C-034
R
REF
+15V
I
OUT
V
IN
R15
+
V
REF
0.01µF
–15V
1kΩ
1µF
V
L
MINIMUM
CAPACITANCE
+5V
0.1µF
FORTURN-ON, V
L
=2.7V
FORTURN-OFF,V
L
=0.7V
1kΩ
1µF
2kΩ100kΩ
50µF
V
OUT
1 ×
PROBE
15kΩ
–15V
0.1µF
14
15
4
2
5
13
6
7
8 9 10 11 12
316
0.1µF
0.1µF
DAC08
Q2
0V
0V
+0.4V
–0.4V
Q1
V
CL
0.7V
Figure 33. Settling Time Measurement