MAX8731 Maxim Integrated Products, MAX8731 Datasheet - Page 15

• Manufacturer Part Number: MAX8731
• Description: SMBus Level 2 Battery Charger
• Manufacturer: Maxim Integrated Products

charge current-regulation loop is in control as long as
the selected battery voltage is below the charge volt-
age set point. When the selected battery voltage reach-
es its set point, the voltage-regulation loop takes control
and maintains the battery voltage at the set point. A
Figure 2. Functional Diagram
ACOK
ACIN
GND
CCV
CCS
CCI
CSSP
CSIN
CSA: CURRENT-SENSE
AMPLIFIER
SMBus Level 2 Battery Charger with
GM
______________________________________________________________________________________
MAX8731
VCC
CSS
A = 20V/V
CSA
LOWEST VOLTAGE CLAMP
GMS
REF/2
POWER-FAIL
CSI
A = 20V/V
LVC
CSA
GMI
100mV
(750mA FOR RS2 = 10mΩ)
150mV
third loop (CCS) takes control and reduces the charge
current when the adapter current exceeds the input
current limit set by the InputCurrent() command.
A functional diagram is shown in Figure 2.
A = 1V/V
ENABLE
IMIN
CCMP
GMV
ZCMD
CONVERTER
DC-DC
Remote Sense
CHARGE VOLTAGE( )
11-BIT DAC
6-BIT DAC
6-BIT DAC
OVP
IMAX
+100mV
CHARGE VOLTAGE ( )
CHARGE CURRENT ( )
INPUT CURRENT ( )
2V
(10A FOR RS2 = 10mΩ)
LEVEL
SHIFT
SMBus LOGIC
REGULATOR
LOW-
SIDE
DRIVER
REFERENCE
LINEAR
4.096V
HIGH-
SIDE
DRIVER
5.4V
BST
DHI
LX
LDO
DLO
PGND
DCIN
V
REF
SCL
SDA
V
CC
DD
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