ADL5309ACBZ-R7 datasheet(19/25 Pages) AD

19 / 25 page

Data Sheet

ADL5309

SERIAL PORT INTERFACE

analog.com

Rev. A | 19 of 25

PROTOCOL

The ADL5309 can be connected to an I2C bus interface as a target

device to control and monitor several internal (analog) functions. Up

to three ADL5309 devices can be connected to the same I2C bus,

each with its own unique device address. See Table 2 for detailed

timing requirements. Data is transferred one byte at a time, with the

MSB first. Each instruction consists of one address byte, followed

by one or more data bytes. The ADL5309 supports single-byte read

and write methods, as well as autoincrement read/write instructions.

ADDRESS SELECTION

The ADL5309 I2C device address can be selected from three

choices by connecting the SBA pin to either ground, the positive

supply, or by leaving the pin floating (see Table 1). The I2C address

selected through the SBA pin can also be read from Register

0x01. The selected 7-bit device address is followed by one read/

write LSB address bit. The LSB address bit equals '0' for a write

instruction and '1' for a read instruction. For example, the write

address corresponding to the I2C device Address 0x6C is obtained

by adding an LSB = 0, equivalent to a left-shift of one bit position

(multiply-by-two), resulting in 0xD8. The bus read address equals

the write address with the LSB changed from '0' to '1', which equals

0xD9.

SUPPORTED READ AND WRITE METHODS

The ADL5309 supports several I2C read and write methods:

►

Read/write a single register

►

Read/write multiple registers in a single operation through auto-

increment

►

Read/write a single shadow register using indirect addressing

Figure 51 summarizes the procedure for each method. Each trans-

action on the I2C bus is initiated by the controller and starts with

sending a start condition, a high to low transition on the SDA line

while SCK is high. Subsequently, the 8-bit device address (of the

selected target) is transmitted, one bit per SCK clock pulse. All

addresses and data are transmitted over the bus with the MSB first.

The ninth clock pulse is reserved to transmit the ACK (acknowl-

edge) signal from the target to the controller to indicate that the

address was received. To send an ACK, the target pulls the SDA

line low. A NACK (not acknowledge) results if the SDA line remains

high. Depending on the transaction, a series of byte read/write

transfers follow, each ending with an ACK or NACK bit. The trans-

action ends with a stop condition sent by the controller and a low to

high transition on the SDA line while SCK is high.

The autoincrement feature provides read/write access to multiple

consecutive registers in a single transaction. Each data byte is read

from/written to the next register, with address one higher than the

previous.

The indirect addressing methods are used to access the ADL5309

shadow registers, as explained in more detail in the Shadow Ac-

cess Registers section.

Figure 51. ADL5309 Serial Bus Read/Write Sequences

ADL5309ACBZ-R7 Scheda tecnica(PDF) 19 Page - Analog Devices

ADL5309ACBZ-R7 Scheda tecnica(HTML) 19 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

Scheda tecnica Scarica

Link URL