DS4432U+ Maxim Integrated Products, DS4432U+ Datasheet - Page 8

• Manufacturer Part Number: DS4432U+
• Description: IC DAC 7BIT 2CH 5.5V 8-MSOP
• Manufacturer: Maxim Integrated Products

Specifications of DS4432U+

• Number Of Bits: 7
• Data Interface: I²C, Serial
• Number Of Converters: 2
• Voltage Supply Source: Single Supply
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Number Of Dac Outputs: 2
• Resolution: 7 bit
• Interface Type: I2C
• Settling Time: 1.3 us
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2.7 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Supply Current: 150 uA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power Dissipation (max): -
• Settling Time: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Dual-Channel, I
Current DAC
Figure 2. I
8
TYPICAL I
Byte Read: A byte read is an 8-bit information trans-
fer from the slave to the master plus a 1-bit ACK or
NACK from the master to the slave. The 8 bits of
information that are transferred (most significant bit
first) from the slave to the master are read by the
master using the bit-read definition, and the master
transmits an ACK using the bit-write definition to
receive additional data bytes. The master must
NACK the last byte read to terminate communication
so the slave returns control of SDA to the master.
Slave Address Byte: Each slave on the I
responds to a slave address byte sent immediately fol-
lowing a START condition. The slave address byte
contains the slave address in the most significant 7
bits, and the R/W bit in the least significant bit. The
DS4432’s slave address is 90h.
When the R/W bit is 0 (such as in 90h), the master is
indicating it will write data to the slave. If R/W = 1
(91h in this case), the master is indicating it wants to
read from the slave. If an incorrect slave address is
written, the DS4432 assumes the master is commu-
nicating with another I
communication until the next START condition is
sent.
Memory Address: During an I
the master must transmit a memory address to iden-
tify the memory location where the slave is to store
the data. The memory address is always the second
byte transmitted during a write operation following
the slave address byte.
START
_______________________________________________________________________________________
A)
B)
EXAMPLE I
SINGLE BYTE WRITE
-WRITE RESISTOR
SINGLE BYTE READ
-READ RESISTOR F8h
F9h TO 00h
MSB
2
2
1
C WRITE TRANSACTION
C Communication Examples
2
C TRANSACTIONS
0
0
ADDRESS
SLAVE
START
START
1
0
1 0 0 1 0 0 0 0
1 0 0 1 0 0 0 0
0
2
90h
90h
C device and ignores the
0
READ/
WRITE
R/W
LSB
SLAVE
SLAVE
ACK
ACK
2
SLAVE
2
C write operation,
ACK
1 1 1 1 1 0 0 1
1 1 1 1 1 0 0 0
C, 7-Bit Sink/Source
MSB
F9h
F8h
b7
b6
REGISTER/MEMORY ADDRESS
2
SLAVE
SLAVE
C bus
ACK
b5
ACK
b4
0 0 0 0 0 0 0 0
REPEATED
START
b3
b2
Writing to a Slave: The master must generate a START
condition, write the slave address byte (R/W = 0), write
the memory address, write the byte of data, and gener-
ate a STOP condition. Remember that the master must
read the slave’s acknowledgement during all byte-write
operations.
Reading from a Slave: To read from the slave, the
master generates a START condition, writes the slave
address byte with R/W = 1, reads the data byte with a
NACK to indicate the end of the transfer, and generates
a STOP condition.
In this example, the typical operating circuit is used to
create Figure 3, a 2.0V voltage supply with ±20% mar-
gin. The adjustable power supply has a DC-DC convert-
er output voltage, V
feedback voltage, V
tionship of R
Substituting V
ship between R
1 0 0 1 0 0 0 1
b1
SLAVE
ACK
91h
LSB
b0
STOP
SLAVE
ACK
SLAVE
0A
ACK
FB
MSB
b7
for an Adjustable Power Supply
and R
V
0A
Applications Information
FB
= 0.8V and V
b6
and R
OUT
DATA
=
R
FB
0B
0A
b5
R
, of 0.8V. To determine the rela-
, of 2.0V and a DC-DC converter
, start with the equation:
0
= 1.5 x R
0B
A
b4
R
DATA
MASTER
0
+
NACK
is determined to be:
B
R
b3
Example Calculation
0
I
OUT
2
B
b2
C Communication
STOP
0B
×
V
= 2.0V, the relation-
b1
OUT
LSB
b0
SLAVE
ACK
STOP