AD5410 Analog Devices, AD5410 Datasheet - Page 22

• Manufacturer Part Number: AD5410
• Description: Single-Channel, 12-/16-Bit, Serial Input, 4 mA to 20 mA, Current Source DAC
• Manufacturer: Analog Devices

Specifications of AD5410

• Resolution (bits): 12bit
• Max Pos Supply (v): +26.4V
• Dac Input Format: SPI

AD5410/AD5420
Table 20. Programmable Slew Time Values in Seconds for a Full-Scale Change on Any Output Range
Update Clock Frequency (Hz)
257,730
198,410
152,440
131,580
115,740
69,440
37,590
25,770
20,160
16,030
10,290
8280
6900
5530
4240
3300
I
Capacitors can be placed between CAP1 and AV
and AV
The capacitors form a filter on the current output circuitry, as
shown in Figure 43, reducing the bandwidth and the slew rate
of the output current. Figure 44 shows the effect the capacitors
have on the slew rate of the output current. To achieve
significant reductions in the rate of change, very large capacitor
values are required, which may not be suitable in some
applications. In this case, the digital slew rate control feature
should be used. The capacitors can be used in conjunction with
the digital slew rate control feature as a means of smoothing out
the steps caused by the digital code increments, as shown in
Figure 45.
OUT
FILTERING CAPACITORS
DD
, as shown in Figure 42.
Figure 42. I
AD5410/
AD5420
AV
GND
OUT
DD
Filtering Capacitors
CAP1
CAP2
AV
I
OUT
DD
C1
C2
DD
1
0.25
0.33
0.43
0.50
0.57
0.9
1.7
2.5
3.3
4.1
6.4
7.9
9.5
12
15
20
, and CAP2
2
0.13
0.17
0.21
0.25
0.28
0.47
0.87
1.3
1.6
2.0
3.2
4.0
4.8
5.9
7.7
9.9
Rev. C | Page 22 of 28
4
0.06
0.08
0.11
0.12
0.14
0.24
0.44
0.64
0.81
1.0
1.6
2.0
2.4
3.0
3.9
5.0
Figure 44. Slew Controlled 4 mA to 20 mA Output Current Step Using
DAC
8
0.03
0.04
0.05
0.06
0.07
0.12
0.22
0.32
0.41
0.51
0.80
1.0
1.2
1.5
1.9
2.5
25
20
15
10
5
0
–0.5
Step Size (LSBs)
External Capacitors on the CAP1 and CAP2 Pins
0
16
0.016
0.021
0.027
0.031
0.035
0.06
0.11
0.16
0.20
0.26
0.40
0.49
0.59
0.74
0.97
1.24
4kΩ
0.5
Figure 43. I
CAP1
R
1.0
SET
NO CAPACITOR
10nF ON CAP1
10nF ON CAP2
47nF ON CAP1
47nF ON CAP2
32
0.008
0.010
0.013
0.016
0.018
0.03
0.05
0.08
0.10
0.13
0.20
0.25
0.30
0.37
0.48
0.62
12.5kΩ
OUT
CAP2
1.5
TIME (ms)
Filter Circuitry
2.0
C1
C2
2.5
64
0.004
0.005
0.007
0.008
0.009
0.015
0.03
0.04
0.05
0.06
0.10
0.12
0.15
0.19
0.24
0.31
T
AV
R
A
LOAD
3.0
DD
= 25°C
40Ω
= 24V
= 300Ω
3.5
AV
128
0.0020
0.0026
0.0034
0.0039
0.0044
0.007
0.014
0.020
0.025
0.03
0.05
0.06
0.07
0.09
0.12
0.16
DD
4.0
BOOST
I
OUT