ISL22349UFV14Z-TK Intersil, ISL22349UFV14Z-TK Datasheet - Page 10

• Manufacturer Part Number: ISL22349UFV14Z-TK
• Description: IC POT DGTL 128TP LN LP 14-TSSOP
• Manufacturer: Intersil
• Series: XDCP™r

Specifications of ISL22349UFV14Z-TK

• Taps: 128
• Resistance (ohms): 50K
• Number Of Circuits: 4
• Temperature Coefficient: 80 ppm/°C Typical
• Memory Type: Non-Volatile
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 14-TSSOP
• Resistance In Ohms: 50K
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Shutdown Mode
The device can be put in Shutdown mode either by pulling the
SHDN pin to GND or setting the SHDN bit in the ACR register
to 0. The truth table for Shutdown mode is in Table 3.
I
The ISL22349 supports an I
protocol. The protocol defines any device that sends data
onto the bus as a transmitter and the receiving device as the
receiver. The device controlling the transfer is a master and
the device being controlled is the slave. The master always
initiates data transfers and provides the clock for both
transmit and receive operations. Therefore, the ISL22349
operates as a slave device in all applications.
All communication over the I
sending the MSB of each byte of data first.
Protocol Conventions
Data states on the SDA line must change only during SCL
LOW periods. SDA state changes during SCL HIGH are
reserved for indicating START and STOP conditions
(see Figure 12). On power-up of the ISL22349 the SDA pin
is in the input mode.
2
C Serial Interface
SHDN pin
High
High
Low
Low
SDA
SCL
SHDN bit
1
1
0
0
TABLE 3.
2
2
10
C bidirectional bus oriented
C interface is conducted by
FIGURE 12. VALID DATA CHANGES, START AND STOP CONDITIONS
START
Normal operation
Shutdown
Shutdown
Shutdown
Mode
STABLE
DATA
ISL22349
CHANGE
DATA
All I
condition, which is a HIGH to LOW transition of SDA while
SCL is HIGH. The ISL22349 continuously monitors the SDA
and SCL lines for the START condition and does not
respond to any command until this condition is met. A
START condition is ignored during the power-up of the
device.
All I
condition, which is a LOW to HIGH transition of SDA while
SCL is HIGH (see Figure 12). A STOP condition at the end
of a read operation, or at the end of a write operation places
the device in its standby mode.
An ACK, Acknowledge, is a software convention used to
indicate a successful data transfer. The transmitting device,
either master or slave, releases the SDA bus after
transmitting eight bits. During the ninth clock cycle, the
receiver pulls the SDA line LOW to acknowledge the
reception of the eight bits of data (See Figure 13).
The ISL22349 responds with an ACK after recognition of a
START condition followed by a valid Identification Byte, and
once again after successful receipt of an Address Byte. The
ISL22349 also responds with an ACK after receiving a Data
Byte of a write operation. The master must respond with an
ACK after receiving a Data Byte of a read operation.
A valid Identification Byte contains 1010b as the four MSBs,
and the following three bits matching the logic values
present at pins A2, A1, and A0. The LSB is the Read/Write
bit. Its value is “1” for a Read operation, and “0” for a Write
operation (see Table 4).
(MSB)
1
2
2
C interface operations must begin with a START
C interface operations must be terminated by a STOP
STABLE
DATA
TABLE 4. IDENTIFICATION BYTE FORMAT
0
Logic values at pins A2, A1, and A0 respectively
1
0
STOP
A2
A1
A0
May 28, 2009
FN6331.3
(LSB)
R/W