s-8243b Seiko Instruments Inc., s-8243b Datasheet - Page 17

• Manufacturer Part Number: s-8243b
• Description: Battry Protection Ic For 3-serial Or 4-serial Cell Pack
• Manufacturer: Seiko Instruments Inc.

Rev.2.5
2.
3. Battery monitor amp circuit
1. 6 0 V battery charging function
1. 7 Delay time setting
Voltage regulator circuit
Built-in voltage regulator can be used to drive a micro computer, etc. The voltage regulator supplies voltage of 3.3 V (3
mA maximum) and an external capacitor is needed.
Caution In the power down condition the voltage regulator output is pulled down to the V
Battery monitor amp sends information of the batteries to a microcomputer. The battery monitor amp output is
controlled and selected by CTL3 and CTL4 pins to give the following two voltages.
After the state of CTL3 and CTL4 are changed, a time between 25 µs and 250 µs is needed for the battery monitor
amp to become stable.
Caution In the power down condition the battery monitor amp output is the V
(a) V
Regarding the charging of a self-discharged battery (0 V battery) the S-8243 has two functions from which one
should be selected.
Caution When the VDD pin voltage is lower than minimum of V
Overcharge detection delay times (t
Overdischarge detection delay times (t
external capacitor at CDT pin. Overcurrent detection delay time 2,3 (t
S-8243AAC, S-8243AAD, S-8243BAE, S-8243BAF
S-8243BAD
(b) N-th offset voltage V
_00
(a) 0 V battery charging is allowed (0 V battery charging is available)
(b) 0 V battery charging is forbidden (0 V battery charging is impossible)
battery voltage, and V
Each battery voltage V
BATn
internal resistor.
When a charger voltage is higher than V
When one of the battery voltages is lower than V
t
t
t
t
t
t
CU
DL
IOV1
CU
DL
IOV1
guaranteed.
= GAMPn × V
V
[ms]
[s]
[ms]
[s]
BATTERYn
[ms]
[ms] = Delay factor (
BATTERY PROTECTION IC FOR 3-SERIAL OR 4-SERIAL CELL PACK
= Delay factor (
= Delay factor (
= Delay factor (
= Delay factor (
= Delay factor (
= (V
OFFn
BATn
BATTERYn
OFFn
BATTERYn
− V
is the n-th offset voltage of the amp.
OFFn
+ V
(n = 1 to 4) is thus calculated by following equation.
) / GAMPn (n = 1, 2, 3, 4)
OFFn
DL1
CU1
33.1
min.
min.
500
555
Seiko Instruments Inc.
50
to t
where GAMPn is the n-th voltage gain of the amp, V
5
5
to t
DL4
1000
1110
66.2
CU4
) and overcurrent detection delay time 1 (t
100
0CHA
typ.
typ.
10
10
) are determined by the external capacitor at the CCT pin.
, 0 V battery can be charged.
1500 ) × C
2220 ) × C
max.
max.
150 ) × C
132 ) × C
0INH
15 ) × C
15 ) × C
, 0 V battery can not be charged.
CT
DT
DT
CT
DT
DT
[µF]
[µF]
[µF]
[µF]
[µF]
[µF]
DSOP
IOV2
, t
, the operation of S-8243 series is not
IOV3
) are fixed internally.
SS
level.
IOV1
S-8243A/B Series
) are determined by the
BATTERYn
SS
level by an
is the n-th
17