AD5315 Analog Devices, AD5315 Datasheet - Page 17

• Manufacturer Part Number: AD5315
• Manufacturer: Analog Devices

Specifications of AD5315

• Resolution (bits): 10bit
• Dac Update Rate: 143kSPS
• Dac Settling Time: 7µs
• Max Pos Supply (v): +5.5V
• Single-supply: Yes
• Dac Type: Voltage Out
• Dac Input Format: I2C/Ser 2-wire,Ser

Table 7. CLR and LDAC Bit Descriptions
Bit
CLR
LDAC
DEFAULT READBACK CONDITION
All pointer byte bits power up to 0. Therefore, if the user
initiates a readback without writing to the pointer byte first, no
single DAC channel has been specified. In this case, the default
readback bits are all 0, except for the CLR bit, which is a 1.
MULTIPLE-DAC WRITE SEQUENCE
Because there are individual bits in the pointer byte for each
DAC, it is possible to simultaneously write the same data and
control bits to 2, 3, or 4 DACs by setting the relevant bits to 1.
MULTIPLE-DAC READBACK SEQUENCE
If the user attempts to read back data from more than one DAC
at a time, the part reads back the default, power-on reset
conditions, that is, all 0s except for CLR , which is 1.
SDA
SDA
SCL
SCL
MASTER
START
COND
BY
Description
[0] All DAC registers and input registers are filled with 0s
on completion of the write sequence.
[1] Normal operation.
[0] All four DAC registers and, therefore, all DAC outputs,
are simultaneously updated on completion of the write
sequence.
[1] Only addressed input register is updated. There is no
change in the contents of the DAC registers.
0
MOST SIGNIFICANT DATA BYTE
MSB
0
0
ADDRESS BYTE
1
1
0
A0
R/W
Figure 33. Write Sequence
LSB
Rev. G | Page 17 of 24
AD53x5
AD53x5
ACK
ACK
BY
BY
MSB
LEAST SIGNIFICANT DATA BYTE
X
MSB
WRITE OPERATION
When writing to the AD5305/AD5315/AD5325 DACs, the user
must begin with an address byte (R/ W = 0), after which the DAC
acknowledges that it is prepared to receive data by pulling SDA
low. This address byte is followed by the pointer byte, which is
also acknowledged by the DAC. Two bytes of data are then written
to the DAC, as shown in Figure 33. A stop condition follows.
READ OPERATION
When reading data back from the AD5305/AD5315/AD5325
DACs, the user begins with an address byte (R/ W = 0), after
which the DAC acknowledges that it is prepared to receive data
by pulling SDA low. This address byte is usually followed by the
pointer byte, which is also acknowledged by the DAC. Following
this, there is a repeated start condition by the master and the
address is resent with R/ W = 1. This is acknowledged by the
DAC indicating that it is prepared to transmit data. Two bytes
of data are then read from the DAC, as shown in Figure 34. A
stop condition follows.
However, if the master sends an ACK and continues clocking
SCL (no STOP is sent), the DAC retransmits the same two bytes
of data on SDA. This allows continuous readback of data from
the selected DAC register.
Alternatively, the user can send a start followed by the address
with R/ W = 1. In this case, the previously loaded pointer settings
are used and readback of data can commence immediately.
X
POINTER BYTE
AD5305/AD5315/AD5325
LSB
LSB
AD53x5
ACK
AD53x5
BY
ACK
BY
MASTER
COND
STOP
BY