IC3410 Datasheet, PDF (5/6 Pages) List of Unclassifed Manufacturers – 10-bit digital to analogue converter IC 3410

Figure 7 Basic connections
Figure 8 Settling time
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a) Positive reference voltage
b) Negative reference voltage
Settling time
The worst case switching condition occurs when all bits
are switched 'on', which corresponds to a low-to-high
transition for all bits. This time is typically 250ns for the
output to settle to within ±1/2 LSB for 10-bit accuracy,
and 200ns for 8-bit accuracy. The turn-off time is typi-
cally 120ns. These times apply when the output swing
is limited to a small (<0.7 volt) swing and the external
output capacitance is under 25pF.
The major carry (MSB off-to-on, all others on-to-off) set-
tles in approximately the same time as when all bits are
switched off-to-on.
If a load resistor of 625 ohms is connected to ground,
allowing the output to swing to -2.5 volts, the settling
time increases to 1.5µs.
Extra care must be taken in board layout as this is usu-
ally the dominant factor in satisfactory test results when
measuring time. Short leads, 100µF supply bypassing,
and minimum scope lead length are all necessary.
A typical test set-up for measuring settling time is
shown in Figure 8. The same set-up for the most part
can be used to measure the slew rate of the reference
amplifier (Figure 10) by typing all data bits high, puls-
ing the voltage reference input between 0 and 2V, and
using a 500Ω load resistor R_L.
t_s - 250 ns TYPICAL
TO ± 1.2 LSB
USE R_L TO GND FOR TURN-OFF MEASUREMENT
FOR SETTLING TIME
MEASUREMENT.
(ALL BIT SWITCHED
LOW TO HIGH)
Figure 9 Propagation delay time
FOR PROPAGATION
DELAY TIME
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