MAX1894XEEE Maxim Integrated, MAX1894XEEE Datasheet - Page 9

• Manufacturer Part Number: MAX1894XEEE
• Description: Battery Management
• Manufacturer: Maxim Integrated
• Series: MAX1894, MAX1924r

Pack-short current fault is latched and is not reset until
the MAX1894/MAX1924 detect a reversal in the direc-
tion of current flow. A charger must be applied to
reverse the current flow (Figure 7).
Figure 2. Undervoltage and Overvoltage Protection Flow Chart
MAX1924 V
MAX1894 V
OV_HYT
OV_HYT
= 200mV
_______________________________________________________________________________________
= 0
TKO, CGO = H
RESET UVF
RESET OVF
Advanced Li+ Battery-Pack Protectors
NO
YES
NO
NO
RESET V
LATCH UVF = UVF + 1
LATCH OVF = OVF + 1
DSO, CGO, TKO = H
V
V
V
UV_TH
STANDBY = 79ms
SRC
V
CGO = DSO = H
OV_TH
V
CELL
SHUTDOWN
V
CELL
V
OV_TH
SRC
TKO = L
CC
OVF = 4
> V
UVF = 4
+ 0.1V
= 2.3V typ &
> V
= 4.25V typ
< V
B4P
> 4.5V
> V
YES
YES
YES
YES
YES
YES
OV_TH
NO
= 4.25V typ
UV_TH
B4P
+ 0.1V
NO
NO
NO
The MAX1894/MAX1924 offer the designer the flexibility
of two charging paths: a fast charging path and a trick-
le-charge path (see Figure 1). Trickle charging is
enabled and TKO is set low when one or more cells are
belows V
Figure 3. Shutdown and Control Pin Flow Charts
SHUTDOWN
DSO, CGO,
TKO = H
UV_TH
.
NO
NO
NO
Fast and Trickle-Charge Paths
NORMAL OPERATION
NORMAL OPERATION
DSO, CGO, TKO = H
DSO, CGO, TKO = H
V
SRC
SHDN = H
Design Procedure
CTL = H
> V
B4P
YES
YES
YES
+ 0.1V
SHUTDOWN PIN
CONTROL PIN
OPERATION
OPERATION
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