Linear Technology Analog Devices LT8708, Datasheet

Page: 57 / 64

LT8708
57
Rev 0
For more information www.analog.com
APPLICATIONS INFORMATION
48V
to
12V
Bidirectional Dual Battery System with FHCM & RHCM
Reverse Operation (DIR
=
0V
)
For
ward Operation (DIR
=
3V
)
+
–
+
–
CSPOUT CSNOUT EXT
V
CC
VOUTLOMON
FBOUT INT
V
CC
GA
TEV
CC
IMON_ON IMON_OP
ICN ICP
IMON_INP IMON_INN CLKOUT
SYNC
SS
RT
V
C
MODE
CSNIN
TG1
BOOST1
SW1
BG1
CSP
CSN
LT8708
GND
BG2
SW2
BOOST2
TG2
CSPIN V
INCHIP
SHDN FBIN VINHIMON
SWEN
LDO33 DIR RVSOFF
120kHz
FWD (3V)
RVS (0V)
+
+
D
B1
D
B2
TO
BOOST1
TO
BOOST2
TO DIODE
D
B1
LD033
V
BA
T2
8708 T
A04a
10V
TO 16V
BA
TTER
Y
(MAX
36V FOR
LOAD DUMP
V
BA
T1
24V
TO 55V
BA
TTER
Y
TO DIODE
D
B2
LD033
I
OUT
I
IN
M3
–M4:
INFINEON BSC010N04LS
C
IN3
: 220
μF
, 100V
C
OUT3
: 330
μF
, 40V
C
IN1
, C
OUT2
, C
IN2
, C
OUT1
: 10
µF
, 100V
, X7R
M5
–M7:
T2N7002AK, TOSHIBA
*SEE UNI AND BIDIRECTIONAL CONDUCTION SECTION FOR MORE DET
AILS.
D
B1
, D
B2
:
CENTRAL SEMI CMMR1U-02-L
TE
L1: 10
μH, SER2918H-103KL
XOR:
DIODES INC. 74AHC1G86SE-7
M1
–M2:
INFINEON BSC026N08NS5
POWER TRANFER DECISION LOGIC
100k
16.9k
M6
M5
18.2k
M7
XOR
68.1k
220pF
4.7
μF
127k 100k
54.9k
220pF
5.6nF
12.1k
365k
1μ
F
4.7
nF
30.1k
10
nF
17.4k
17.4k
10
nF
10
nF
4.7
nF
4.7
nF
17.4k
13.3k
23.7k
4.7
μF
3.3
Ω
12.1k
4.7
μF
133k
1μ
F
100k 681k
12.1k 93.1k
178k
C
OUT3
C
OUT2
C
OUT1
2m
Ω
1Ω
0.22
μF
M4
M2
M3
L1 10
μH
1Ω
1.5m
Ω
10
Ω
10
Ω
1nF
1nF
3.3nF
1Ω
0.22
μF
1Ω
M1
C
IN3
C
IN2
C
IN1
5m
Ω
1μ
F
20k
340k
340k
*
V
BA
T1
24V
TO 55V
+
–
V
BA
T2
10V TO 16V
+ –
18.2k
340k
12.1k
133k
FBIN
PREVENT DISCHARGING V
BA
T1
BELOW 24V
CHARGE V BA
T2
TO
14.5V
FBOUT
LIMIT V
BA
T2
CHARGING
CURRENT TO 15A
5m
Ω
2m
Ω
POWER FLOW
8708 T
A04b
V
BA
T1
24V
TO 55V
+
–
V
BA
T2
10V TO 16V
+
–
18.2k
340k
12.1k
93.1k
FBIN
PREVENT
DISCHARGING V
BA
T2
BELOW
10.5V
CHARGE V
BA
T1
TO 48V
VOUTLOMON
LIMIT V
BA
T1
CHARGING
CURRENT TO 4A
5m
Ω
POWER FLOW
8708 T
A04c
2m
Ω
17.8k
16.9k
LD033
RVS (0V)
100k