AD5327BRUZ Analog Devices Inc, AD5327BRUZ Datasheet - Page 22

• Manufacturer Part Number: AD5327BRUZ
• Description: IC DAC 12BIT QUAD 2.5V 16-TSSOP
• Manufacturer: Analog Devices Inc

Specifications of AD5327BRUZ

• Data Interface: Serial
• Settling Time: 8µs
• Number Of Bits: 12
• Number Of Converters: 4
• Voltage Supply Source: Single Supply
• Power Dissipation (max): 4.5mW
• Operating Temperature: -40°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 16-TSSOP
• Resolution (bits): 12bit
• Sampling Rate: 125kSPS
• Input Channel Type: Serial
• Supply Voltage Range - Analog: 2.5V To 5.5V
• Supply Current: 500µA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AD5307/AD5317/AD5327
DAISY CHAINING
For systems that contain several DACs, or where the user
wishes to read back the DAC contents for diagnostic purposes,
the SDO pin can be used to daisy-chain several devices together
and provide serial readback. Figure 4 shows the timing diagram
for daisy-chain applications. The daisy-chain mode is enabled
by connecting DCEN high (see Figure 46).
1
ADDITIONAL PINS OMITTED FOR CLARITY.
68HC11
MISO
Figure 46. AD5307 in Daisy-Chain Mode
MOSI
1
SCK
PC7
PC6
DIN
SCLK
SYNC
LDAC
SCLK
SYNC
LDAC
SCLK
SYNC
LDAC
AD5307
AD5307
AD5307
SDO
SDO
SDO
DIN
DIN
DCEN
DCEN
DCEN
1
1
1
Rev. C | Page 22 of 28
POWER SUPPLY BYPASSING AND GROUNDING
In any circuit where accuracy is important, careful consideration
of the power supply and ground return layout helps to ensure
the rated performance. The printed circuit board on which the
AD5307/AD5317/AD5327 are mounted should be designed so
that the analog and digital sections are separated and confined
to certain areas of the board. If the AD5307/AD5317/AD5327
are in a system where multiple devices require an AGND-to-
DGND connection, the connection should be made at one
point only. The star ground point should be established as close
as possible to the device. The AD5307/AD5317/AD5327 should
have ample supply bypassing of 10 μF in parallel with 0.1 μF on
the supply located as close to the package as possible, ideally right
up against the device. The 10 μF capacitors are the tantalum bead
type. The 0.1 μF capacitor should have low effective series
resistance (ESR) and low effective series inductance (ESI), such
as is typical of the common ceramic types that provide a low
impedance path to ground at high frequencies to handle
transient currents due to internal logic switching.
The power supply lines of the AD5307/AD5317/AD5327 should
use as large a trace as possible to provide low impedance paths
and reduce the effects of glitches on the power supply line. Com-
ponents, such as clocks, with fast switching signals should be
shielded with digital ground to avoid radiating noise to other
parts of the board, and they should never be run near the refer-
ence inputs. Avoid crossover of digital and analog signals. Traces
on opposite sides of the board should run at right angles to each
other. This reduces the effects of feedthrough on the board. A
microstrip technique is by far the best, but it is not always
possible with a double-sided board. In this technique, the com-
ponent side of the board is dedicated to ground plane, and signal
traces are placed on the solder side.