ADT7517ARQ Analog Devices Inc, ADT7517ARQ Datasheet - Page 39

• Manufacturer Part Number: ADT7517ARQ
• Description: IC TEMP SNSR QUAD DAC 16-QSOP
• Manufacturer: Analog Devices Inc

Specifications of ADT7517ARQ

• Rohs Status: RoHS non-compliant
• Function: Temp Monitoring System (Sensor)
• Topology: ADC, Comparator, Multiplexer, Register Bank
• Sensor Type: External & Internal
• Sensing Temperature: -40°C ~ 120°C, External Sensor
• Output Type: I²C™, MICROWIRE™, QSPI™, SPI™
• Output Alarm: No
• Output Fan: No
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 120°C
• Mounting Type: Surface Mount
• Package / Case: 16-QSOP

Writing Data to a Register
All registers are 8-bit registers, therefore only one byte of data
can be written to each register. Writing a single byte of data to
one of these read/write registers consists of the serial bus
address, the data register address written to the address pointer
register, followed by the data byte written to the selected data
register. This is illustrated in Figure 61. To write to a different
register, another start or repeated start is required. If more than
one byte of data is sent in one communication operation, the
addressed register is repeatedly loaded until the last data byte
has been sent.
Reading Data from the ADT7516/ADT7517/ADT7519
Reading data from the ADT7516/ADT7517/ADT7519 is done
in a one-byte operation. Reading back the contents of a register
is shown in Figure 62. The register address had previously been
set up by a single-byte write operation to the address pointer
register. To read from another register, write to the address
pointer register again to set up the relevant register address.
Thus, block reads are not possible, that is, no I
SPI Serial Interface
The SPI serial interface of the ADT7516/ADT7517/ADT7519
consists of four wires: CS , SCLK, DIN, and DOUT. The CS is
used to select the device when more than one device is connected
SDA
SCL
SDA
SCL
START BY
MASTER
START BY
MASTER
Figure 61. I
1
1
1
1
0
0
SERIAL BUS ADDRESS BYTE
SERIAL BUS ADDRESS BYTE
2
C—Writing to the Address Pointer Register Followed by a Single Byte of Data to the Selected Register
0
0
1
FRAME 1
FRAME 1
1
Figure 62. I
A2
SDA (CONTINUED)
SCL (CONTINUED)
A2
2
C auto-increment.
A1
2
A1
C—Reading a Single Byte of Data from a Selected Register
A0
ADT7616/ADT7517/ADT7519
ADT7516/ADT7517/ADT7519
A0
R/W
R/W
Rev. B | Page 39 of 44
ACK. BY
ACK. BY
9
D 7
9
1
D7
1
SINGLE DATA BYTE FROM ADT7516/ADT7517/ADT7519
D 6
P7
1
to the serial clock and data lines. The CS is also used to
distinguish between any two separate serial communications
(see Figure 67 for a graphical explanation). The SCLK is used to
clock data in and out of the part. The DIN line is used to write
to the registers, and the DOUT line is used to read data back
from the registers. The recommended pull-up resistor value is
between 500 Ω and 820 Ω. Strong pull-ups are needed when
serial clock speeds that are close to the maximum limit are used
or when the SPI interface lines are experiencing large capacitive
loading. Larger resistor values can be used for pull-up resistors
when the serial clock speed is reduced.
The part operates in slave mode and requires an externally
applied serial clock to the SCLK input. The serial interface is
designed to allow the part to be interfaced to systems that
provide a serial clock that is synchronized to the serial data.
There are two types of serial operations, read and write.
Command words are used to distinguish read operations from
write operations. These command words are given in Table 23.
Address auto-increment is possible in SPI mode.
Table 23. SPI Command Words
Write
0x90 (1001 0000)
D6
P6
D5
D5
ADDRESS POINTER REGISTER BYTE
D 4
P5
D4
DATA BYTE
FRAME 3
P4
D3
FRAME 2
D3
FRAME 2
P3
D 2
ADT7516/ADT7517/ADT7519
ADT7516/ADT7517/ADT7519
D2
P2
D 1
ADT7516/ADT7517/ADT7519
D1
D0
P1
NO ACK. BY
D0
MASTER
Read
0x91 (1001 0001)
ACK. BY
P0
9
9
ACK. BY
9
STOP BY
MASTER
STOP BY
MASTER