TIMEOUT FEATURE
t_timeout, the LMP91000’s I2C interface will be reset so that
the SDA line will be released. Since the SDA is an open-drain
with an external resistor pull-up, this also avoids high power
consumption when LMP91000 is driving the bus and the SCL
is stopped.
The timeout is a safety feature to avoid bus lockup situation.
If SCL is stuck low for a time exceeding t_timeout, the
LMP91000 will automatically reset its I2C interface. Also, in
the case the LMP91000 hangs the SDA for a time exceeding
REGISTERS
The registers are used to configure the LMP91000.
If writing to a reserved bit, user must write only 0. Readback value is unspecified and should be discarded.
Register map
Address
0x00
Name
STATUS
LOCK
Power on default
Access
Read only
R/W
Lockable?
0x00
0x01
N
N
0x01
0x02 through 0x09
0x10
RESERVED
TIACN
0x03
0x20
0x00
R/W
R/W
R/W
Y
Y
N
0x11
REFCN
0x12
MODECN
RESERVED
0x13 through 0xFF
STATUS -- Status Register (address 0x00)
The status bit is an indication of the LMP91000's power-on status. If its readback is “0”, the LMP91000 is not ready to accept other
I2C commands.
Bit
Name
Function
[7:1]
RESERVED
Status of Device
0 Not Ready (default)
1 Ready
0
STATUS
LOCK -- Protection Register (address 0x01)
The lock bit enables and disables the writing of the TIACN and the REFCN registers. In order to change the content of the TIACN
and the REFCN registers the lock bit needs to be set to “0”.
Bit
Name
Function
[7:1]
RESERVED
Write protection
0
LOCK
0 Registers 0x10, 0x11 in write mode
1 Registers 0x10, 0x11 in read only mode (default)
www.ti.com
14
TI [ TEXAS INSTRUMENTS ]
