LT8584
33
8584fb
For more information www.linear.com/LT8584
Typical applicaTions
Stackable Fast-Charge 8 to 12-Cell Battery Module
Application Notes
1. Channels 3 through 11 are omitted for clarity. These
channels should be integrated similar to channel 2. Not
all required components for the LTC680x are shown.
Consult the LTC680x data sheet for recommended
components and their connections.
2. Up to 20 LT8584 balancers may be connected in paral
-
lel to
farther increase discharge current. The DCHRG
pin
can also drive an enable pin of a separate DC/DC
converter like the LT3750 capacitor charger.
3. Multiple modules can be stacked in series to achieve
a larger battery stack. Each module must contain an
integer multiple of the total number of cells in the stack.
For instance, an 80 cell stack should be constructed with
8 modules each having 10 cells. Use consecutive BSM
channels starting with BSM channel 1when populating
a module with less than 12 channels. Tie all unused
LTC680x C pins to MODULE+.
4. Place one CnE capacitor close to the Master LT8584’s
transformer primary, and place the other CnE capacitor
close to the Slave LT8584’s transformer primary. The
symbol ‘n’ denotes a particular channel ranging from
1 to 12.
5. Place RCD snubber composed of DnF, DnE, RnC, RnD,
CnB, CnH
, as close as possible to the respective trans-
former
primary.
The symbol ‘n’ denotes a particular
channel ranging from 1 to 12.
6. R
PASS
and M1 may be omitted for applications using
only one module in the stack.
7. Each LT8584 channel should have no less than 650mm
2
of PCB pad footprint for proper heat sinking.
8. Consult Application Engineering for proper communica-
tion with
LTC680x family of parts as well as a proper
algorithm for extracting cell parameters.
9.
Recommended for cells that operate within a 2.5V to
5.3V range.
Stackable 8 to 12-Cell Battery Module Application
Notes
See the last page Typical Application.
1. Channels 4 through 11 are omitted for clarity. These
channels should be integrated similar to channel 2. Not
all required components for the LTC680x are shown.
Consult the LTC680x data sheet for recommended
components and their connections.
2. Multiple modules can be stacked in series to achieve
a larger battery stack. Each module must contain an
integer multiple of the total number of cells in the stack.
For instance, an 80 cell stack should be constructed with
8 modules each having 10 cells. Use consecutive BSM
channels starting with BSM channel 1 when populating
a module with less than 12 channels. Tie all
unused
LTC680x C pins to MODULE+.
3.
Place the CnB capacitor close to the LT8584’s trans
-
former primary. The RCD snubber composed of CnE,
RnC and DnD should also be placed close the LT8584’s
transformer primary. The symbol ‘n’ denotes a particular
channel ranging from 1 to 12.
4. The BSM V
+
pin may share cell 12’s positive battery
connection, and the BSM V
–
pin may share cell 0’s
negative battery connection as long as the summa-
tion of
each battery connection’s PCB trace, wire, and
inter
connection resistance is less than 60mΩ.
5. R
PASS
and M1 may be omitted for applications using
only one module in the stack.
6. Each LT8584 channel should have no less than 650mm
2
of PCB pad footprint for proper heat sinking.
7. Consult Application Engineering for proper communica-
tion with
LTC680x family of parts as well as a proper
algorithm for extracting cell parameters.
8.
Recommended for cells that operate within a 2.5V to
5.3V range.
