AAT3601_08 Datasheet, PDF (31/37 Pages) Advanced Analogic Technologies – Total Power Solution for Portable Applications

PRODUCT DATASHEET
AAT3601178
Total Power Solution for Portable Applications
START and STOP Conditions
START and STOP conditions are always generated by the
master. Prior to initiating a START condition, both the
SDA and SCL pin are idle mode (idle mode is when there
is no activity on the bus and SDA and SCL are pulled to
V_CC via external resistor). As depicted in Figure 9, a
START condition is defined to be when the master pulls
the SDA line low and after a short period pulls the SCL
line low. A START condition acts as a signal to the ICs
that something is about to be transmitted on the BUS.
A STOP condition, also shown in Figure 9, is when the
master releases the bus and SCL changes from low to
high followed by SDA low to high transition. The master
does not issue an ACKNOWLEGE and releases the SCL
and SDA pins.
Transferring Data
Every byte on the bus must be 8 bits long. A byte is always
sent with a most significant bit first (see Figure 10).
MSB
LSB R/W
Figure 10: Bit Order.
The address is embedded in the first seven bits of the
byte. The eighth bit is reserved for the direction of the
information flow for the next byte of information. For the
AAT3601, this bit must be set to “0”. The full 8-bit
address including the R/W bit is 0x98 (hex) or 10011000
in binary.
Acknowledge Bit
Acknowledge bit is the ninth bit of data. It is used to
send back a confirmation to the master that the data has
been received properly. For acknowledge to take place,
the MASTER must first release the SDA line, then the
SLAVE will pull the data line low as shown in Figure 9.
Serial Programming Code
After sending the chip address, the master should send
an 8-bit data stream to select which register to program
and then the codes that the user wishes to enter.
Register 0x00:
Timer
Register 0x01:
Not used
RCHG₁
Not used
Register 0x02:
LDO5₁
LDO5₀
RCHG₀
CHG₂
CHG₁
CHG₀
Not used
Not used
Not used
SYS
LDO4₁
LDO4₀
LDO3₁
LDO3₀
Figure 11: Serial Programming Register Codes.
Term₁
LDO1₁
LDO2₁
Term₀
LDO1₀
LDO2₀
USE_USB Pin
1
0
X
X
X
X
X
X
X
CHG₂
0
0
0
0
0
1
1
1
1
CHG₁
0
0
0
1
1
0
0
1
1
CHG₀
0
0
1
0
1
0
1
0
1
Constant Current Charge I_{CH_CC}
100mA (fixed internally)
800mA (set by ISET resistor)
640mA
480mA
320mA
960mA
1120mA
1280mA
1440mA
Constant Current Charge as
% of ISET current
(default)
100% (default)
80%
60%
40%
120%
140%
160%
180%
Table 4: CHG Bit Setting for the Constant Current Charge Level
(I_SET resistor = default 800mA charge current).
3601.2008.07.1.1
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