ADT7463ARQZ ON Semiconductor, ADT7463ARQZ Datasheet - Page 11

• Manufacturer Part Number: ADT7463ARQZ
• Description: IC REMOTE THERMAL CTRLR 24-QSOP
• Manufacturer: ON Semiconductor
• Series: dBCool®r

Specifications of ADT7463ARQZ

• Function: Fan Control, Temp Monitor
• Topology: ADC, Comparator, Fan Speed Counter, Multiplexer, Register Bank
• Sensor Type: External & Internal
• Sensing Temperature: -40°C ~ 120°C, External Sensor
• Output Type: SMBus™
• Output Alarm: No
• Output Fan: Yes
• Voltage - Supply: 3 V ~ 5.5 V
• Operating Temperature: -40°C ~ 120°C
• Mounting Type: Surface Mount
• Package / Case: 24-QSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

When reading data from a register, there are two possibilities:
1. If the ADT7463’s address pointer register value is unknown
2. If the address pointer register is already at the desired address,
REV. C
or not the desired value, it is first necessary to set it to the
correct value before data can be read from the desired data
register. This is done by performing a write to the ADT7463
as before, however, only the data byte is sent and this con-
tains the register address. This is shown in Figure 8.
A read operation is then performed consisting of the serial
bus address, R/W bit set to 1, followed by the data byte read
from the data register. This is shown in Figure 9.
data can be read from the corresponding data register without
first writing to the address pointer register, so Figure 8 can
be omitted.
SDA
SDA
SCL
SCL
START BY
START BY
MASTER
MASTER
1
0
1
0
1
1
0
0
SERIAL BUS ADDRESS
SERIAL BUS ADDRESS
Figure 9. Reading Data from a Previously Selected Register
1
1
FRAME 1
Figure 8. Writing to the Address Pointer Register Only
FRAME 1
BYTE
BYTE
1
1
A1
A1
Rev. 4 | Page 11 of 52 | www.onsemi.com
A0
A0
R/W
R/W
ADT7463
ACK. BY
ADT7463
ACK. BY
9
9
–11–
D7
D7
1
1
Notes
1. It is possible to read a data byte from a data register without
2. In Figures 7 to 9, the serial bus address is shown as the
3. In addition to supporting the Send Byte and Receive Byte
4. If it is required to perform several read or write operations in
first writing to the address pointer register if the address
pointer register is already at the correct value. However, it is
not possible to write data to a register without writing to the
address pointer register because the first data byte of a write
is always written to the address pointer register.
default value 01011(A1)(A0), where A1 and A0 are set by
the address select mode function previously defined.
protocols, the ADT7463 also supports the Read Byte protocol
(see System Management Bus specifications Rev. 2.0 for
more information).
succession, the master can send a repeat start condition
instead of a stop condition to begin a new operation.
D6
D6
ADDRESS POINTER REGISTER BYTE
D5
D5
DATA BYTE FROM ADT7463
D4
D4
FRAME 2
FRAME 2
D3
D3
D2
D2
D1
D1
D0
D0
NO ACK. BY
MASTER
ADT7463
ACK. BY
9
9
ADT7463
STOP BY
STOP BY
MASTER
MASTER