AD9709AST Analog Devices Inc, AD9709AST Datasheet - Page 18

• Manufacturer Part Number: AD9709AST
• Description: IC DAC 8BIT DUAL 125MSPS 48-LQFP
• Manufacturer: Analog Devices Inc
• Series: TxDAC+®r

Specifications of AD9709AST

• Rohs Status: RoHS non-compliant
• Settling Time: 35ns
• Number Of Bits: 8
• Data Interface: Parallel
• Number Of Converters: 2
• Voltage Supply Source: Analog and Digital
• Power Dissipation (max): 450mW
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 48-LQFP
• For Use With: AD9709-EBZ - BOARD EVAL FOR AD9709

AD9709
SLEEP MODE OPERATION
The AD9709 has a power-down function that turns off the
output current and reduces the supply current to less than
8.5 mA over the specified supply range of 3.3 V to 5 V and
temperature range. This mode can be activated by applying a
Logic Level 1 to the SLEEP pin. The SLEEP pin logic threshold
is equal to 0.5 × AVDD. This digital input also contains an active
pull-down circuit that ensures the AD9709 remains enabled if
this input is left disconnected. The AD9709 requires less than
50 ns to power down and approximately 5 μs to power back up.
POWER DISSIPATION
The power dissipation, P
factors, including
•
•
•
•
The power dissipation is directly proportional to the analog
supply current, I
is directly proportional to I
insensitive to f
Conversely, I
f
Figure 35 show I
ratios (f
DVDD2 = 5 V and DVDD1 = DVDD2 = 3.3 V, respectively.
Note how I
DVDD1/DVDD2 is reduced from 5 V to 3.3 V.
CLK
, and digital supply (DVDD1/DVDD2). Figure 34 and
the power supply voltages (AVDD and DVDD1/DVDD2)
the full-scale current output (I
the update rate (f
the reconstructed digital input waveform
OUT
/f
DVDD
CLK
DVDD
CLK
) for various update rates with DVDD1 =
is reduced by more than a factor of 2 when
AVDD
DVDD
.
is dependent on the digital input waveform,
, and the digital supply current, I
as a function of full-scale sine wave output
CLK
D
, of the AD9709 is dependent on several
)
OUTFS
, as shown in Figure 33, and is
OUTFS
)
DVDD
. I
AVDD
Rev. B | Page 18 of 32
35
30
25
20
15
10
18
16
14
12
10
80
70
60
50
40
30
20
10
5
0
8
6
4
2
0
0
0
0
Figure 35. I
Figure 34. I
0.1
0.1
5
DVDD
DVDD
Figure 33. I
vs. Ratio @ DVDD1 = DVDD2 = 3.3 V
vs. Ratio @ DVDD1 = DVDD2 = 5 V
RATIO (
RATIO (
0.2
0.2
10
I
OUTFS
125MSPS
100MSPS
65MSPS
25MSPS
AVDD
5MSPS
f
f
OUT
OUT
(mA)
vs. I
/
/
f
f
0.3
CLK
0.3
CLK
15
OUTFS
125MSPS
100MSPS
65MSPS
25MSPS
5MSPS
)
)
0.4
0.4
20
0
0
2
.5
.5
5