LTC6803HG-3#PBF Linear Technology, LTC6803HG-3#PBF Datasheet - Page 31

• Manufacturer Part Number: LTC6803HG-3#PBF
• Manufacturer: Linear Technology
• Type: Battery Monitoringr

Specifications of LTC6803HG-3#PBF

• Battery Type: Li-Ion
• Operating Supply Voltage (min): 4V
• Operating Temp Range: -40C to 125C
• Package Type: SSOP
• Mounting: Surface Mount
• Pin Count: 44
• Operating Temperature Classification: Automotive
• Lead Free Status / RoHS Status: Compliant

APPLICATIONS INFORMATION
situation might occur in a modular battery system during
initial installation or a service procedure. The daisy-chain
ports are protected from the reverse potential in this sce-
nario by external series high voltage diodes required in
the upper port data connections as shown in Figure 14.
During the charging phase of operation, this fault would
lead to forward biasing of daisy-chain ESD clamps that
would also lead to part damage. An alternative connection
to carry current during this scenario will avoid this stress
from being applied (Figure 14).
Internal Protection Diodes
Each pin of the LTC6803 has protection diodes to help
prevent damage to the internal device structures caused
by external application of voltages beyond the supply rails
as shown in Figure 15. The diodes shown are conventional
silicon diodes with a forward breakdown voltage of 0.5V.
The unlabeled Zener diode structures have a reverse-
breakdown characteristic which initially breaks down at
12V then snaps back to a 7V clamping potential. The Zener
diodes labeled Z
initial reverse breakdown of 30V snapping back to 25V.
The forward voltage drop of all Zeners is 0.5V. Refer to
Figure 15 in the event of unpredictable voltage clamping
or current flow. Limiting the current flow at any pin to
±10mA will prevent damage to the IC.
PROTECT
AGAINST
BREAK
HERE
Figure 14. Reverse-Voltage Protection for
the Daisy Chain (One Link Connection Shown)
+
+
REDUNDANT
OPTIONAL
CURRENT
CLAMP
PATH
are higher voltage devices with an
V
V
–
+
SDO
(NEXT HIGHER IN STACK)
(NEXT LOWER IN STACK)
SDOI
SDI
LTC6803-1
LTC6803-1
SCKO
SCKI
CSBO
CSBI
860313 F14
RSO7J
×3
READING EXTERNAL TEMPERATURE PROBES
The LTC6803 includes two channels of ADC input, V
and V
(tempco about –4%/°C generally) or diodes (–2.2mV/°C
typical) located within the cell array. Sensors can be
powered directly from V
60µA total).
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
4
5
6
7
8
9
NOTE: NOT SHOWN ARE PN DIODES TO ALL OTHER PINS FROM PIN 30
V
C12
S12
C11
S11
C10
S10
C9
S9
C8
S8
C7
S7
C6
S6
C5
S5
C4
S4
C3
S3
C2
S2
C1
S1
C0
+
TEMP2
, that are intended to monitor thermistors
Figure 15. Internal Protection Diodes
LTC6803-1/LTC6803-3
30
V
–
Z
Z
Z
CLAMP
CLAMP
CLAMP
REF
LTC6803-3
as shown in Figure 16 (up to
Z
Z
Z
CLAMP
CLAMP
CLAMP
Z
Z
Z
CLAMP
CLAMP
CLAMP
V
V
V
GPIO2
GPIO1
WDTB
31
TEMP2
TEMP1
SCKO
CSBO
MODE
SDOI
V
CSBI
SCKI
V
SDO
TOS
REG
SDI
REF
680313 F15
TEMP1
680313f
35
34
33
32
44
43
42
41
40
39
38
37
36
3
2
1