DS2741 Maxim Integrated Products, DS2741 Datasheet - Page 9

• Manufacturer Part Number: DS2741
• Description: Current Monitor and Accumulator
• Manufacturer: Maxim Integrated Products

Figure 6. I
COMMUNICATIONS KEY
ble, and generates a STOP condition. See Figure 6
for a read example using the repeated START condi-
tion to specify the starting memory location.
Reading Multiple Bytes from a Slave: The read
operation can be used to read multiple bytes with a
single transfer. When reading bytes from the slave,
the master simply ACKs the data byte if it desires to
read another byte before terminating the transaction.
After the master reads the last byte, it NACKs to
indicate the end of the transfer and generates a
STOP condition. This can be done with or without
modifying the address counter’s location before the
read cycle. The DS2741’s address counter does not
wrap on page boundaries during read operations,
but the counter rolls from its uppermost memory
address FFh to 00h if the last memory location is
read during the read transaction.
WRITE TWO BYTES WITH A SINGLE TRANSACTION TO SLAVE ADRESS 68h
READ A SINGLE BYTE WITH A DUMMY WRITE CYCLE TO SET THE ADDRESS COUNTER FROM SLAVE ADDRESS 68h
READ TWO BYTES WITH A DUMMY WRITE CYCLE TO SET THE ADDRESS COUNTER FROM SLAVE ADDRESS 68h
SR
S
P
S
S
S
0 1 1 0
0 1 1 0
0 1 1 0
START
STOP
REPEATED
START
2
C Communications Examples
A
N
1
1
1
X X X X X X X X
0
0
0
_______________________________________________________________________________________
ACK
NACK
0 0
0 0
0 0
Current Monitor and Accumulator with
A
A
A
WHITE BOXES INDICATE THE MASTER IS
CONTROLLING SDA
SHADED BOXES INDICATE THE SLAVE IS
CONTROLLING SDA
MEMORY ADDRESS
MEMORY ADDRESS
MEMORY ADDRESS
8-BIT ADDRESS OR DATA
A
A
A
SR 0 1 1 0
SR 0 1 1 0
Integrated Sense Resistor
DATA
1
1
To achieve best results, it is recommended that the power
supply is decoupled with a 0.01µF or a 0.1µF capacitor.
Use high-quality, ceramic, surface-mount capacitors, and
mount the capacitors as close as possible to the V
GND pins to minimize lead inductance.
SDA is an open-collector output on the DS2741 that
requires a pullup resistor to realize high logic levels. A
master using either an open-collector output with a
pullup resistor or a push-pull output driver can be used
for SCL. Pullup resistor values should be chosen to
ensure that the rise and fall times listed in the AC elec-
trical characteristics are within specification.
For the latest package outline information and land patterns, go
to www.maxim-ic.com/packages.
0
0
PACKAGE TYPE
NOTES
0 1
0 1
1) ALL BYTES ARE SENT MOST SIGNIFICANT BIT FIRST.
2) THE FIRST BYTE SENT AFTER A START CONDITION
14 TDFN-EP
A
IS ALWAYS THE SLAVE ADDRESS FOLLOWED BY
THE READ/WRITE BIT.
A
A
DATA
Applications Information
DATA
DATA
SDA and SCL Pullup Resistors
PACKAGE CODE
Package Information
Power-Supply Decoupling
T1433+2
A
P
N
A
P
www.DataSheet4U.com
DATA
DOCUMENT NO.
21-0137
N
CC
P
and
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