AD5621 Analog Devices, AD5621 Datasheet - Page 18

• Manufacturer Part Number: AD5621
• Description: 2.7 V to 5.5 V,
• Manufacturer: Analog Devices

Specifications of AD5621

• Resolution (bits): 12bit
• Dac Update Rate: 1.7MSPS
• Dac Settling Time: 6µs
• Max Pos Supply (v): +5.5V
• Single-supply: Yes
• Dac Type: Voltage Out
• Dac Input Format: Ser,SPI

AD5601/AD5611/AD5621
APPLICATIONS
CHOOSING A REFERENCE AS POWER SUPPLY FOR
THE AD5601/AD5611/AD5621
The AD5601/AD5611/AD5621 come in tiny LFCSP and SC70
packages with less than a 100 µA supply current. Because of
this, the choice of reference depends on the application
requirements. For applications with space-saving requirements,
the
and has excellent drift at 9 ppm/°C (3 ppm/°C in the R-8 package)
and provides very good noise performance at 3.4 µV p-p in the 0.1
Hz to 10 Hz range.
Because the supply current required by the AD5601/AD5611/
AD5621 is extremely low, the parts are ideal for low supply
applications. The
this case. It requires less than 100 µA of quiescent current and
can, therefore, drive multiple DACs in one system, if required. It
also provides very good noise performance at 8 µV p-p in the
0.1 Hz to 10 Hz range.
Some recommended precision references for use as supplies to
the AD5601/AD5611/AD5621 are listed in Table 7.
Table 7. Precision References for the AD5601/AD5611/AD5621
Part No.
ADR435
ADR425
ADR02
ADR02
ADR395
INTERFACE
ADR02
Figure 51. ADR395 as Power Supply to the AD5601/AD5611/AD5621
SERIAL
3-WIRE
is recommended. It is available in an SC70 package
Initial
Accuracy
(mV max)
±2
±2
±3
±3
±5
7V
SYNC
SCLK
SDIN
ADR395
ADR395
Temp Drift
(ppm/°C max)
3 (R-8)
3 (R-8)
3 (R-8)
3 (SC70)
9 (TSOT-23)
voltage reference is recommended in
AD5601/AD5611/
5V
AD5621
0.1 Hz to 10 Hz
Noise (µV p-p typ)
8
3.4
10
10
8
V
OUT
= 0V TO 5V
Rev. F | Page 18 of 24
BIPOLAR OPERATION USING THE
AD5601/AD5611/AD5621
The AD5601/AD5611/AD5621 have been designed for single-
supply operation, but a bipolar output range is also possible
using the circuit shown in Figure 52. The circuit in Figure 52
gives an output voltage range of ±5 V. Rail-to-rail operation at
the amplifier output is achievable using an
the output amplifier.
The output voltage for any input code can be calculated as
where D represents the input code in decimal (0 – 2
With V
This is an output voltage range of ±5 V, with 0x0000 corre-
sponding to a −5 V output and 0x3FFF corresponding to a
+5 V output.
+5V
V
V
Figure 52. Bipolar Operation with the AD5601/AD5611/AD5621
OUT
OUT
DD
= 5 V, R1 = R2 = 10 kΩ
=
=
10µF






V
10
DD
2
×
N
 ×
0.1µF
D


2



D
N
−
V
AD5601/AD5611/

× 

DD
5
V



INTERFACE
R1 = 10kΩ
AD5621
R1
3-WIRE
SERIAL
R1
+
R2
V



OUT
−
V
DD
AD820
R2 = 10kΩ
AD820/
OP295
+5V
–5V
 ×
Data Sheet


R2
R1
or
N



).



OP295
+5V
as