BQ2050_15 Datasheet, PDF (10/27 Pages) Texas Instruments – Lithium Ion Power Gauge™ IC

Not Recommended For New Designs
bq2050
Written by Host to bq2050 Received by Host to bq2050
CMDR = 03h
NAC = 65h
LSB
MSB LSB
MSB
Break 1 1 0 0 0 0 0 0 1 0 1 0 0 1 1 0
DQ
TD205002.eps
Figure 3. Typical Communication With the bq2050
bq2050 Registers
Primary Status Flags Register (FLGS1)
The bq2050 command and status registers are listed in The read-only FLGS1 register (address=01h) contains
Table 7 and described below.
the primary bq2050 flags.
Command Register (CMDR)
The write-only CMDR register is accessed when eight
valid command bits have been received by the bq2050.
The CMDR register contains two fields:
n W/R bit
n Command address
The W/R bit of the command register is used to select whether
the received command is for a read or a write function.
The W/R values are:
CMDR Bits
7
65
4
3
2
1
0
W/R - -
-
-
-
-
-
Where W/R is:
0 The bq2050 outputs the requested register con-
tents specified by the address portion of CMDR.
1 The following eight bits should be written
to the register specified by the address por-
tion of CMDR.
The lower seven-bit field of CMDR contains the address
portion of the register to be accessed. Attempts to write
to invalid addresses are ignored.
The charge status flag (CHGS) is asserted when a
valid charge rate is detected. Charge rate is deemed
valid when VSRO > VSRQ. A VSRO of less than VSRQ or
discharge activity clears CHGS.
The CHGS values are:
FLGS1 Bits
7
65
4
3
2
1
0
CHGS - -
-
-
-
-
-
Where CHGS is:
0 Either discharge activity detected or VSRO <
VSRQ
1 VSRO > VSRQ
The battery replaced flag (BRP) is asserted whenever
the bq2050 is reset either by application of VCC or by a
serial port command. BRP is reset when either a valid
charge action increments NAC to be equal to LMD, or a
valid charge action is detected after the EDV1 flag is as-
serted. BRP = 1 signifies that the device has been reset.
The BRP values are:
FLGS1 Bits
7
65
4
3
2
1
0
- BRP -
-
-
-
-
-
CMDR Bits
765 4
3
2
1
0
-
AD6 AD5 AD4
AD3
AD2
AD1
AD0
(LSB)
Where BRP is:
0 Battery is charged until NAC = LMD or dis-
charged until the EDV1 flag is asserted
1 bq2050 is reset
10