LTC3567 Datasheet, PDF (18/28 Pages) Linear Technology – High Effi ciency USB Power Manager Plus 1A Buck-Boost Converter with I2C Control

LTC3567
OPERATION
Table 2. I²C Serial Port Mapping (Defaults 0xFF00 in Reset State or if DV_CC = 0V)
A7 A6 A5 A4 A3 A2 A1 A0
B7
B6
B5 B4 B3
Reserved for Internal
Use
Switching Regulator
Voltage (See Table 4)
Disable
Battery
Charger
Buck-Boost
Regulator
Mode (See
Table 5)
Reserved for Internal
Use
B2
Enable
Buck-Boost
Regulator
B1
B0
Input Current Limit
(See Table 3)
Table 3. USB Current Limit Settings
B1
B0
USB SETTING
0
0
1x Mode (USB 100mA Limit)
0
1
10x Mode (Wall 1A Limit)
1
0
Suspend
1
1
5x Mode (USB 500mA Limit)
Table 4. Buck-Boost Regulator Servo Voltage
A3 A2 A1 A0
SWITCHING REGULATOR
SERVO VOLTAGE
0
0
0
0
0.425V
0
0
0
1
0.450V
0
0
1
0
0.475V
0
0
1
1
0.500V
0
1
0
0
0.525V
0
1
0
1
0.550V
0
1
1
0
0.575V
0
1
1
1
0.600V
1
0
0
0
0.625V
1
0
0
1
0.650V
1
0
1
0
0.675V
1
0
1
1
0.700V
1
1
0
0
0.725V
1
1
0
1
0.750V
1
1
1
0
0.775V
1
1
1
1
0.800V
Table 5. Buck-Boost Switching Regulator Modes
B6
SWITCHING REGULATOR MODE
0
PWM Mode
1
Burst Mode Operation
the total of one address byte and two data bytes. Each
data byte is transferred to an internal holding latch upon
the return of an Acknowledge. After both data bytes have
been transferred to the LTC3567, the master may terminate
the communication with a Stop condition. Alternatively, a
Repeat-Start condition can be initiated by the master and
another chip on the I²C bus can be addressed. This cycle
can continue indefinitely and the LTC3567 will remember
the last input of valid data that it received. Once all chips on
the bus have been addressed and sent valid data, a global
Stop condition can be sent and the LTC3567 will update its
command latch with the data that it had received.
In certain circumstances the data on the I²C bus may
become corrupted. In these cases the LTC3567 responds
appropriately by preserving only the last set of complete
data that it has received. For example, assume the LTC3567
has been successfully addressed and is receiving data
when a Stop condition mistakenly occurs. The LTC3567
will ignore this Stop condition and will not respond until
a new Start condition, correct address, new set of data
and Stop condition are transmitted.
Likewise, with only one exception, if the LTC3567 was
previously addressed and sent valid data but not updated
with a Stop, it will respond to any Stop that appears on
the bus, independent of the number of Repeat-Starts that
have occurred. If a Repeat-Start is given and the LTC3567
successfully acknowledges its address and first byte, it
will not respond to a Stop until both bytes of the new data
have been received and acknowledged.
Disabling the I²C Port
The I²C serial port can be disabled by grounding the DV_CC
pin. In this mode, control automatically passes to the
individual logic input pins EN1 and CHRGEN. However,
with the I²C port disabled, the programmable buck-boost
switching regulator defaults to a fixed servo voltage of 0.8V
in PWM mode, and the USB input current limit defaults to
1x mode (100mA limit). By default the battery charger will
be enabled and the buck-boost will be disabled.
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