LT8584
27
8584fb
For more information www.linear.com/LT8584
OPERATING PARALLELED LT8584s
Multiple LT8584s may be used if more discharge current
is required. The LT8584 connected to a battery stack
monitor (LTC6804 is recommended) becomes the mas
-
ter balancer. Connect its MODE pin to ground. Limit the
maximum
number
of parallel slave balancers to 20. This
gives a maximum discharge current of 50A. Other con-
verters may
also be used as a slave, including the LT3751
(must
connect its V
IN
to the cell above) and the LT3750.
Connect all slave MODE pins to V
IN
. This forces those parts
into simple mode and makes their DCHRG pin an input pin.
applicaTions inForMaTion
Connect all slave DCHRG pins (SHDN pins if using other
converters) to the master DCHRG pin. Figure 13 shows a
5A discharger circuit using two LT8584s.
Each part operates asynchronously from the other one.
Use separate transformers for each LT8584 balancer.
The slave balancers operate only when the master balancer
is operating. A fault on the master balancer will turn off all
slave balancers. A fault in any of the slave balancers will
not turn off any of the other balancers. Use an external
sense resistor, R
SNS
, and the V
SNS
pin to determine if the
average current is at the expected value.
Figure 13. LT8584 Parallel Operation
LT8584
V
IN
V
SNS
SNS
V
CELL
GND
TO ADJACENT
OUT PIN
TO ADJACENT
OUT PIN
SW
DCHRG
RTMR
MODE
OUT
D
IN
SLAVE BALANCERMASTER BALANCER
TO C PIN
TO S PIN
8584 F13
MODULE+
MODULE–
•
•
LT8584
V
IN
V
SNS
V
CELL
GND
SW
DCHRG
RTMR
MODE
OUT
D
IN
•
•
BAT
BAT
–
BAT
–
BAT
–
Figure 14. LT 8584 Suggested Layout
1
2
3
4
5
6
7
8
R1
16
15
14
13
12
11
10
9
17
• •
C
FBO
R
SNS
V
IN
DCHRG
D
IN
OUT
GND
GND
RTMR
C
VCELL
C
VIN
C
OUT
V
SNS
V
CELL
V
IN
BATTERY
STACK
GROUND
TOP OF
BATTERY
STACK
BATTERY
STACK
GROUND
TOP OF
BATTERY
STACK
D1
1
2
3
4
5
6
7
8
THERMAL VIAS
SERIAL MODE SIMPLE MODE
16
15
14
13
12
11
10
9
17
• •
C
T1T1
V
IN
D
IN
OUT
GND
GND
V
IN
D1
8584 F14
C
VTRAN
CELL INPUT
C
VCELL
C
VTRAN
C
OUT
CELL INPUT