MAX16047A Datasheet, PDF (45/61 Pages) Maxim Integrated Products – 12-Channel/8-Channel EEPROM-Programmable System Managers with Nonvolatile Fault Registers

12-Channel/8-Channel EEPROM-Programmable
System Managers with Nonvolatile Fault Registers
Acknowledge
The acknowledge bit (ACK) is the 9th bit attached to
any 8-bit data word. The receiving device always gen-
erates an ACK. The MAX16047A/MAX16049A generate
an ACK when receiving an address or data by pulling
SDA low during the 9th clock period (Figure 11). When
transmitting data, such as when the master device
reads data back from the MAX16047A/MAX16049A, the
device waits for the master device to generate an ACK.
Monitoring ACK allows for detection of unsuccessful
data transfers. An unsuccessful data transfer occurs if
the receiving device is busy or if a system fault has
occurred. In the event of an unsuccessful data transfer,
the bus master should reattempt communication at a
later time. The MAX16047A/MAX16049A generate a
NACK after the command byte is received during a
software reboot, while writing to the EEPROM, or when
receiving an illegal memory address.
Slave Address
Use the slave address input, A0, to allow multiple identi-
cal devices to share the same serial bus. Connect A0 to
GND, DBP (or an external supply voltage greater than
2V), SCL, or SDA to set the device address on the bus.
See Table 25 for a listing of all possible 7-bit addresses.
Table 25. Setting the I²C/SMBus Slave
Address
A0
SLAVE ADDRESS
0
1010 00XR
1
1010 01XR
SCL
1010 10XR
SDA
1010 11XR
X = Don’t care, R = Read/write select bit.
1
SCL
CLOCK PULSE FOR ACKNOWLEDGE
2
8
9
SDA BY
TRANSMITTER
S
SDA BY
RECEIVER
NACK
ACK
Figure 11. Acknowledge
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