Samsung F8278X Computer Hardware User Manual


 
BATTERY LEVEL DETECTOR S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X
15-2
BATTERY LEVEL DETECTOR CONTROL REGISTER (BLDCON)
The bit 3 of BLDCON controls to run or disable the operation of Battery Level Detector. Basically this V
BLD
is set
as 2.2V by system reset and it can be changed in 3 kinds voltages by selecting Battery Level Detector Control
Register (BLDCON). When you write 3-bit data value to BLDCON, an established resistor string is selected and
the V
BLD
is fixed in accordance with this resistor. Table 15-1 shows specific V
BLD
of 3 levels.
Battery Level Detector Control Register
F4H, Set 1, Bank 1, R/W, Reset : 00H
.7 .6 .5 .4 .3 .2 .1 .0MSB LSB
Not used
+
Comparator
Mux
BANDGAP
BLD Enable/Disable
BLD
OUT
Bias
V
REF
V
IN
R
BLD
V
BLDREF
Resistor String
P2CONL.1-.0
V
BAT
NOTES:
1. The reset value of BLDCON is #00H.
2. V
REF
is about 1 volt.
f
BLD
Figure 15-2. Battery Level Detect Circuit and Control Register
Table 15-1. BLDCON Value and Detection Level
BLDCON .2.0
V
BLD
0 0 0 2.2 V
1 0 1 2.4 V
0 1 1 2.8 V
Other values Not available