ds2760bx-025-t-r Maxim Integrated Products, Inc., ds2760bx-025-t-r Datasheet - Page 15

• Manufacturer Part Number: ds2760bx-025-t-r
• Description: Ds2760 High-precision Li+ Battery Monitor
• Manufacturer: Maxim Integrated Products, Inc.

1-WIRE CRC GENERATION BLOCK DIAGRAM Figure 14
HARDWARE CONFIGURATION
Because the 1-Wire bus has only a single line, it is important that each device on the bus be able to drive
it at the appropriate time. To facilitate this, each device attached to the 1-Wire bus must connect to the
bus with open-drain or tri-state output drivers. The DS2760 used an open-drain output driver as part of
the bidirectional interface circuitry shown in Figure 15. If a bidirectional pin is not available on the bus
master, separate output and input pins can be tied together.
The 1-Wire bus must have a pull-up resistor at the bus-master end of the bus. For short line lengths, the
value of this resistor should be approximately 5k W . The idle state for the 1-Wire bus is high. If, for any
reason, a bus transaction must be suspended, the bus MUST be left in the idle state in order to properly
resume the transaction later. If the bus is left low for more than 120
interpret the low period as a Reset Pulse, effectively terminating the transaction.
1-WIRE BUS INTERFACE CIRCUITRY Figure 15
TRANSACTION SEQUENCE
The protocol for accessing the DS2760 via the 1-Wire port is as follows:
§ Initialization
§ Net Address Command
§ Function Command
§ Transaction/Data
The sections that follow describe each of these steps in detail.
MSb
Rx
Tx
BUS MASTER
+V
XOR
PULLUP
Rx = Receive
Tx = Transmit
4.7k W
(2.0V–5.5V)
15
XOR
1 m A
Typ.
DS2760 1-WIRE PORT
m
s, slave devices on the bus begin to
100 W
MOSFET
LSb
Rx
Tx
XOR
input