AD9785-EBZ Analog Devices Inc, AD9785-EBZ Datasheet - Page 52

• Manufacturer Part Number: AD9785-EBZ
• Description: BOARD EVAL FOR AD9785
• Manufacturer: Analog Devices Inc
• Series: TxDAC®r

Specifications of AD9785-EBZ

• Number Of Dac's: 2
• Number Of Bits: 12
• Outputs And Type: 2, Differential
• Sampling Rate (per Second): 800M
• Data Interface: Serial
• Settling Time: 22ms
• Dac Type: Current
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 85°C
• Utilized Ic / Part: AD9785
• Silicon Manufacturer: Analog Devices
• Application Sub Type: DAC
• Kit Application Type: Data Converter
• Silicon Core Number: AD9785
• Kit Contents: Board
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

AD9785/AD9787/AD9788
POWER DISSIPATION
Figure 74 through Figure 78 detail the power dissipation of the
AD9785/AD9787/AD9788 under a variety of operating conditions.
All of the graphs are taken with data being supplied to both the
I and Q channels. The power consumption of the device does
not vary significantly with changes in the modulation mode or
analog output frequency. Graphs of the total power dissipation
are shown along with the power dissipation of the DVDD18,
DVDD33, and CVDD18 supplies.
1800
1600
1400
1200
1000
1400
1200
1000
Figure 75. Power Dissipation, Digital 1.8 V Supply, I and Q Data,
800
600
400
200
800
600
400
200
Figure 74. Power Dissipation, I and Q Data, Dual DAC Mode
0
0
0
0
50
50
8× NCO
100
100
Dual DAC Mode
8× NCO
8×
f
8×
f
DATA
DATA
150
150
(MSPS)
(MSPS)
4× NCO
1× NCO
4×
1×
200
200
2×
250
250
2× NCO
4× NCO
4×
2×
1× NCO
1×
2× NCO
300
300
Rev. A | Page 52 of 64
The power dissipation of the AVDD33 supply rail is independent
of the digital operating mode and sample rate. The current drawn
from the AVDD33 supply rail is typically 51 mA (182 mW) when
the full-scale current of the I and Q DACs is set to the nominal
value of 20 mA. Changing the full-scale current directly impacts
the supply current drawn from the AVDD33 rail. For example,
if the full-scale current of the I DAC and the Q DAC is changed
to 10 mA each, the AVDD33 supply current drops to 31 mA.
Figure 76. Power Dissipation, Digital 3.3 V Supply, I and Q Data,
120
100
Figure 77. Power Dissipation, Clock 1.8 V Supply, I and Q Data,
70
60
50
40
30
20
10
80
60
40
20
0
0
0
0
50
50
100
100
Dual DAC Mode
Dual DAC Mode
f
f
DATA
DATA
150
150
(MSPS)
(MSPS)
2× NCO
2×
1× NCO
1×
200
200
250
250
8× NCO
8×
4× NCO
4×
2× NCO
2×
1× NCO
1×
4× NCO
4×
8× NCO
8×
300
300