AIC AIC1782CS Dual-battery charge controller Datasheet

AIC1782
Dual-Battery Charge Controller
FEATURES
Quick and Easy Testing for Production.
Sequential
Charging
Control
of
Two
NiMH/NiCd Battery Packs.
Reliable Sequential Fast Charge Control of
Dual NiMH and/or NiCd Battery Packs, even
with a Fluctuating Charging Current.
Fast Charge Termination by: ∆T / ∆t , −∆V,
0 ∆V , Safety Timer, Maximum Temperature,
Maximum Voltage.
Safety Timer and ∆T / ∆t Detection Slope
Linearly Adjustable.
Battery Voltage Protection Range Selectable.
Mode of Battery Temperature Protection Selectable.
Protection against Battery Voltage and Battery
Temperature Faults.
Selectable LED Display Mode for Battery
Status.
Five Pulsed Trickle Charge Modes.
Discharge-before-Charge Function Available to
Eliminate Memory Effect.
20-pin DIP or SO Packages.
DESCRIPTION
Notebook and Laptop Personal Computers.
Portable Power Tools and Toys.
Portable Communication Equipments.
Portable Video & Stereo Equipments.
over battery pack B, represented by BTS and
BBV pin signals. The AIC1782 automatically
switches charging current to charge the standby
battery pack after the battery pack being charged
finishes its charging or encounters a fault condition. −∆V (-0.25%) detection, 0 ∆V (peak voltage
timer) detection, and ∆T / ∆t detection are the
primary methods employed by the AIC1782 to
terminate fast charge. The fast charge can also
be cut off by maximum battery voltage and
maximum battery temperature detection along
with the safety timer to prevent charging under
been proved powerful in terminating fast charging
reliable decision of ending fast charge and prevent
80
Cell Voltage
1.35
60
1.25
40
misaction caused by using −∆V detection alone
Temperature (°C)
Cell Voltage (V)
sented by input signals of ATS and ABV pins,
Both ∆T / ∆t and − ∆V detection methods have
100
1.45
under certain conditions. Fig. 1 shows an example
of charging curve of a battery charged by a fluctuating current from a NiMH battery charger which
uses the AIC1782 controller IC to achieve optimal
charging. The ∆T / ∆t or −∆V detection circuitry
may be disabled independently for different appli-
Temperature
30
40
50
60
20
Charge Time (min.)
Fig. 1
quence gives priority to battery pack A, repre-
the combination of these two methods to achieve
Charge Current = 600m A
Cell Capaci ty = 550m A
Ni MH B attery
20
After powered on, the AIC1782 charging se-
for NiMH and NiCd batteries. The AIC1782 utilizes
1.55
10
and NiCd batteries without the risk of malfunction.
battery itself.
Dual-Battery Fast Chargers for:
Mobile Phones.
0
for intelligent sequential charging of dual NiMH
fault conditions of the charging system or the
APPLICATIONS
1.15
The AIC1782 fast charge controller is designed
Battery Charging Characteristics Resulted from
an AIC1782-Controlled Charger with a Fluctuating Charging Current
cations, such as system-integrated chargers,
chargers with varying charge current, or battery
packs lack of temperature sensing thermistor.
Analog Integrations Corporation
4F, 9, Industry E. 9th Rd, Science Based Industrial Park, Hsinchu Taiwan, ROC
DS-1782-00
TEL: 886-3-5772500 FAX: 886-3-5772510
www.analog.com.tw
1
AIC1782
The safety timer period, mode of battery tem-
rid of memory effect of NiCd batteries without the
perature protection, battery voltage protection
risk of overdischarging. Test mode is provided for
range, pulsed trickle charge duty, and LED dis-
charger manufactures to dramatically reduce
play mode are all adjustable or selectable. Dis-
production test time.
charge-before-charge function is included to get
TYPICAL APPLICATION CIRCUIT
R1
R3
R2
R27
1N4148
R28
VIN
VCC
FB
R22
470
R4
390
R5
20/5W
R21
2.7K
Q1
D468
VIN
+
78L05
C9
100µF
R33
47K
1.5K
AIC1563
1N5820
D5
R25
470
Q5
3904
R26
330
B2
D8
1N4148
+
2.2µF
C12
1M
R36
3
680
B
C5
0.1µF
VCC(5V)
5
R11
+
C6
100µF
C7
0.1µF
R12
6
R13
VCC(5V)
7
R14 8
R24
2.7K
100K
B1
A
C8
0.1µF
VCC(5V)
R16
BBV
DIS
LEB2 18
R20
LED4
680
LEB1
17
R19
LED3
680
GND 16
BTS
VCC
SEL1 15
ADJ
SEL2
SEL3
TMR
MODE
9
ATS
R15
19
AIC1782
R32
R10
20
SW1
2
Q7
D468
DSW
ICOB
VCC 5V
4
D2
1N4148
A1012
Q4
1N4148
D3
R35
ABV
LED5
R37
3.9K
VCC(5V)
R23
330
Q3
3904
VCC(5V)
IS
1N5820
D4
THERMISTOR
GND
0.1/2W
C11
220µF
BST
C10
1nF
R30
220
200µH
+
D1
1N5821
A1012
Q2
THERMISTOR
TC
RS
1
C4
0.1µF
4.7µF
BATTERY B
SE
1N4148
L1
C3
R7 +
BATTERY A
150
SC
4.7K
C2
0.1µF
C1
4.7µF
R8 100K
R6
D7
1K
A1012
Q6
R29
+
D6
4.7K
R34
100K
R17 10
LEA1
680
ICOA
LEA2
14
13
12
11
R18 LED2
680
LED1
Battery Charger for Dual NiMH and NiCd Battery
2
AIC1782
ORDERING INFORMATION
AIC1782 XX
ORDER NUMBER
PACKAGE TYPE
N: PLASTIC DIP
S: SMALL OUTLINE
PIN CONFIGURATION
AIC1782 CN
ABV
1
20 DSW
(PLASTIC DIP)
BBV
2
19 ICOB
DIS 3
18 LEB2
TEMPERATURE RANGE
C= 0°C~70°C
AIC1782 CS
BTS
4
17 LEB1
VCC
5
16 GND
ADJ
6
15 SEL1
SEL3 7
14 SEL2
TMR 8
13 MODE
(PLASTIC SO)
9
12 ICOA
LEA1 10
11 LEA2
ATS
ABSOLUTE MAXIMUM RATINGS
Supply Voltage
.........................................................……………........................... 5.5V
DC Voltage Applied on any Pin
.......................................…………........................ 5.5V
Sink Current of ICOA Pin, LEA1 and LEA2 Pins ................………...................... 20mA
Sink Current of ICOB Pin, LEB1 and LEB2 Pins
Operating Temperature Range
................……......................... 20mA
....................................…………................... 0°C~ 70°C
Storage Temperature Range ...........................................………….........
-65°C~ 150°C
TEST CIRCUIT
Voltage
Source
-
+
ABV
DSW
BBV
ICOB
DIS
LEB2
BTS
LEB1
VCC
GND
Voltage Source
-
+
YELLOW
R1
560
-
+
Voltage Source
VCC (5V)
VCC
V1 (0.95V)
ADJ
AIC1782
R3
ORANGE
560
R4
GREEN
560
R5
RED
560
VCC
SEL1
VCC
V2 (3V)
100K
SEL3
SEL2
TMR
MODE
ATS
ICOA
LEA1
LEA2
VCC
R2
-
+
Voltage Source
RED
VCC
R6
560
R8
ORANGE
560
R7
GREEN
560
3
AIC1782
ELECTRICAL CHARACTERISTICS (Ta=25°°C,
VCC=5V, unless otherwise speci-
fied.)
PARAMETER
TEST CONDITIONS
SYMBOL
Supply Voltage
VCC
Supply Current
ICC
Battery Low
Before Initial Timer
After Initial Timer
(SEL3>3V)
Source Current
Capability
MAX.
UNIT
4.5
5
5.5
V
1.1
0.21
0.63
0.69
0.75
(SEL3<2V)
1.1
1.2
1.3
Battery High
(SEL3>3V)
2.6
2.7
2.8
(SEL3<2V)
1.9
2.0
2.1
Recommended External
Resistor of TMR pin
−∆V detection level w.r.t.*
Peak Value
V
Temperature High
VATS
1.35
1.45
1.55
Temperature Low
VBTS
3.5
3.6
3.7
140
250
Ω
25
50
Ω
MΩ
ZDIS
LEA1, LEA2, LEB1,
LEB2, ICOA, ICOB pins
ON
OFF
SEL3 pin
DSW pin
1
ISEL3
IDSW
MODE, SEL1, SEL2
pins
Input Impedance
mA
0.16
Output impedance of DIS
Pin
Output Impedance
TYP.
0.11
Voltage Protection Limit
Temperature Sense
Limit
VABV
VBBV
MIN.
ABV, BBV, ATS, BTS,
ADJ pins
5.5
16
µA
µA
300
KΩ
1
RTM
2
V
MΩ
100
1000
KΩ
R
-0.25
%
*: with respected to
4
AIC1782
TYPICAL
PERFORMANCE CHARACTERISTICS
(Ta=25°°C, R2=100KΩ
Ω,
VCC=5V, refer to Test Circuit)
Safety Timer vs Supply Volatge
Supply Current vs Supply Voltage
1.18
Safety Timer (min.)
Supply Current (mA)
81.0
1.12
1.06
80.5
80.0
79.5
1.00
4.4
4.6
4.8
5.0
5.2
79.0
5.4
4.4
4.6
4.8
Safety Timer vs Temperature
5.2
5.4
Supply Current vs Temperature
82.0
1.26
Supply Current (mA)
Safety Timer (min.)
5.0
VCC (V)
VCC (V)
81.0
80.0
1.14
1.02
0.90
79.0
0
20
40
60
80
0
20
40
60
Temperature(°C)
Temperature (°C)
ABV and BBV (High) Limit vs Temperature
(SEL3>3V)
ABV and BBV (High) Limit vs Temperature
(SEL3<2V)
2.74
80
2.03
ABV, BBV (V)
ABV, BBV (V)
2.02
2.70
2.66
2.62
0
20
40
Temperature (°C)
60
80
2.00
1.98
0
20
40
60
80
Temperature (°C)
5
AIC1782
TYPICAL
PERFORMANCE CHARACTERISTICS (Continued)
Output Impedance vs Temperature
(LEA’s, LEB’s, ICO’s pins)
ABV and BBV (Low) Limit vs Temperature
(Before Initial Timer)
29
0.163
Output Impedance(Ω)
ABV, BBV (V)
0.162
0.160
0.158
27
25
23
0
20
40
60
0
80
20
Temperature (°C)
40
60
80
Temperature(°C)
ABV and BBV (Low ) limits vs Temperature
(SEL3<2V, After Initial Timer)
ABV and BBV (Low) limits vs Temperature
(SEL3>3V, After Initial Timer)
0.710
1.22
ABV, BBV (V)
ABV, BBV (V)
0.705
1.21
0.700
1.20
1.19
0.695
0
20
40
60
80
0.690
0
20
40
60
80
Temperature (°C)
Temperature (°C)
ATS and BTS (High) Limit vs Temperature
ATS and BTS (Low) Limit vs Temperature
1.48
3.61
ATS, BTS (V)
ATS, BTS (V)
3.62
3.60
1.46
1.44
3.59
3.58
0
20
40
Temperature (°C)
60
80
1.42
0
20
40
60
80
Temperature (°C)
6
AIC1782
BLOCK DIAGRAM
GND VCC
MODE
SEL3
SEL1
SEL2
ADJ
Bandgap
Reference
& Voltage
Regulator
MODE
Selection
Battery Voltage
& Temperature
Protection
Setting
LED Display&
Trickle Charge
Duty Setting
TMR
LEB2 LEB1
LEA2
Oscillator
Timing
Control Unit
LEA1
Display
Control
Unit
Charge Control
State Machine
Charge
Control Unit
∆T/∆t Detection
Setting
Battery Temperature
Protection
ICOB
ICOA
DIS
13-bit A/D
Discharge
Control Unit
Battery Voltage
Protection
+
DSW
CHARGE END
ATS
BTS
ABV
BBV
PIN DESCRIPTIONS
range of BTS pin is 0.29 VCC to
0.72 VCC.
PIN 1: ABV - Divided battery voltage input to
sense the battery voltage of
pack A.
PIN 2: BBV - Divided battery voltage input to
sense the battery voltage of
pack B.
PIN 3: DIS
PIN 5: VCC
- Power supply input at 5V ±
10%.
PIN 6: ADJ
- For adjusting the slope of
∆T / ∆t . Acceptable voltage
range for this pin is approximately 0.28V to 3.8V. If voltage higher than VCC - 0.3V,
function of ∆T / ∆t detection is
disabled.
PIN 7: SEL3
- Determining the acceptable
voltage range of ABV and
BBV pins and mode of temperature protection function.
- Push-pull output, used to control an external transistor to discharge the battery of pack B.
DIS is active high when function
of discharge is enabled.
PIN 4: BTS - The battery cell temperature of
pack B is represented as a voltage input to the AIC1782 at this
pin. The acceptable voltage
7
AIC1782
PIN 8: TMR
- Determining the period of
safety timer with an external
resistor connected to GND.
PIN 9: ATS
- The battery cell temperature
of pack A is represented as a
voltage input to the AIC1782
at this pin. the acceptable
voltage range of ATS is 0.29
VCC to 0.72 VCC.
PIN 10: LEA1 &
PIN 11: LEA2 - Open-drained outputs used to
indicate the charging status of
the battery pack A.
PIN 12: ICOA
- Open-drained output, used to
control the charging current of
the battery pack A.
PIN 13: MODE - Determining the mode of operation for the AIC1782.
PIN 14: SEL2 &
PIN 15: SEL1
PIN 16: GND
- Tri-level inputs, that jointly
control the LED display mode
and the duty of trickle charge
after the completion of fast
charge.
- Power ground.
PIN 17: LEB1 &
PIN 18: LEB2
- Open-drained outputs used to
indicate the charging status of
battery pack B
PIN 19: ICOB
- Open-drained output, used to
control the charging current of
the battery pack B.
PIN 20: DSW
- Controlling the function of discharge-before-charge of the
battery pack B. (See discharge-before-charge
subsection in application informations).
APPLICATION INFORMATIONS
THE AIC1782 OPERATION
Power-on and Battery Prequalifying
The AIC1782 is a sequential charger, initiating a
acceptable limits of ABV and BBV are determined by the input voltage of SEL3 pin and the
acceptable temperature sense voltage window
for ATS and BTS are 0.29 VCC to 0.72 VCC.
charge action on either battery pack A or B.
When power is first applied to the AIC1782, all
internal digital circuit of the AIC1782 are reset
by the internal power-on-reset circuitry, the output of LED‘s (depending on the setting of SEL1
and SEL2 pins) flash 3 times to indicate the initiation of power-on. If both battery pack A and B
are present when VCC is applied to the AIC1782,
the charge action begins with battery pack A if
conditions are acceptable.
The AIC1782 controls the initiation of a charge
action and checks for acceptable battery voltage and temperature prior to fast charging. If
the voltage of ABV or BBV fail to fall within the
predetermined acceptable limits, the corresponding battery pack enters a chargingsuspending mode. If the voltage of ATS or BTS
is outside the 0.29 VCC to 0.72 VCC window, action to AIC1782 is determined by the input voltage of SEL3 pin.
Condition of battery pack A is examined through
the ATS and ABV pins, while battery pack B is
examined through the BTS and BBV pins. The
Discharge-Before-Charge
8
AIC1782
The AIC1782 provides the function of dis-
In the course of fast charge, the AIC1782 con-
charge-before-charge
NiCd
stantly monitors the battery voltage and tem-
batteries which suffer from memory effect. This
perature through ABV (or BBV) and ATS (or
function can only be activated for pack B after
BTS) pins. The fast charge process is regis-
the prequalification of battery voltage and tem-
tered complete when any one of the following
perature, yet before the charge completion is
situations is encountered, which are explained
registered for fast charge cycle of pack B.
below:
Negative delta voltage (-∆V).
Peak voltage timer ( 0 ∆V ).
Delta temperature/ delta time ( ∆T / ∆t ).
Maximum charge time.
Maximum battery voltage.
Maximum battery temperature.
to
precondition
To trigger this function, DSW pin has to be biased to GND over 0.18 second. After discharge
begins, LEB1 and LEB2 pins are both OFF,
ICOB pin is ON, and DIS pin goes high to activate an external circuit to discharge the battery
pack B until the voltage of BBV pin fall below
0.9V (or 0.69V, depending on the input voltage
-∆
∆V Cutoff
of SEL3 pin) or DSW pin is biased to GND for
The AIC1782 makes a voltage sampling at ABV
over 0.18 second again. The application circuit
(or BBV) pin every 4 seconds when safety timer
is
period is set equal to 80 minutes. If a negative
included
in
TYPICAL
APPLICATION
CIRCUIT.
delta voltage of 0.25% compared to its peak
value is detected at ABV (or BBV) pin, the fast
Fast Charge
After the battery passes fault checks, charge
begins on either of the batteries, the other bat-
charge cycle is terminated.
0∆
∆V Cutoff
tery remains in a waiting state until the first bat-
If the battery voltage stays at its peak value or
tery terminates fast charge. The AIC1782 will
decreases very slowly for the duration deter-
automatically switch to fast charge the second
mined by the peak voltage timer, which is in turn
battery. The battery pack A has the priority over
equal 3.7% of safety timer, the fast charge ac-
battery pack B only when power is first applied
tion is terminated.
to the AIC1782. When fast charging begins, the
initial and safety timer of the AIC1782 start
counting. Functions of -∆V detection, Peak voltage timer, ∆T / ∆t detection, and maximum
battery voltage are, however, disabled tempo-
∆T/∆
∆t Cutoff
The ∆T / ∆t detection of the AIC1782 is performed by sensing the decrease of ATS (or BTS)
pin voltage in a specific timer interval dictated
rarily until the initial timer period in the initial
by the safety timer. The fast charging termi-
stage of a charge cycle elapses. The initial timer
nates when the decrease of ATS (or BTS) pin
period is equal to 1/80 of safety timer.
voltage in 56 seconds exceeds the predetermined value set by ADJ pin input. This time in-
Since the low limit of acceptable ABV or BBV
voltage are only about 0.16V during the initial
timer period, even deeply discharged batteries
can easily qualify to be fast charged subse-
terval of 56 seconds is based on the assumption that voltage of ATS (or BTS) pin is sampled
once for every 8 seconds, which is also determined by safety timer.
quently.
14
AIC1782
Functioning of -∆V detection and peak voltage
The acceptable battery voltage range of ABV
timer ( 0 ∆V ) can be disabled if the MODE pin is
and BBV pins and mode of temperature protec-
biased to GND. Functioning of ∆T / ∆t detection
can be disabled if the voltage of ADJ pin is
tion function is determined by the voltage of
higher than VCC - 0.3V.
Maximum Safety Timer Cutoff
The maximum fast charge period is determined
by the safety timer, which is set by a resistor
connected from TMR pin to GND. Safety timer,
SEL3 pin, shown as the following:
(a) SEL3 > VCC - 0.3V
Acceptable ABV/BBV Range:
Before initial timer: 0.16V~2.7V
After initial timer: 0.69V~2.7V
Temperature Protection Mode:
-∆V sampling rate, and ∆T / ∆t sampling rate
will be longer if the resistor value is larger.
Entering charge-suspending mode when tem-
When the value of the resistor is 100KΩ, the
abnormal battery voltage. Latch for charge-
safety timer period equals 80 minutes. This can
suspending function is provided for high tem-
be verified by biasing MODE pin to VCC and the
perature protection, but not for low temperature
measured frequency on DSW pin should be
protection.
perature is either too low or too high, same as
around 32.8 KHz. After the safety timer period is
finished, the fast charge action is terminated.
(b) VCC - 1.4V> SEL3 >
V cc - 0.4V
2
Acceptable ABV/BBV Range:
Before initial timer: 0.16V~2.7V
After initial timer: 0.69V~2.7V
Maximum Voltage and Temperature Cutoff
The AIC1782 guards against the maximum
limits for battery voltage and temperature during
Temperature Protection Mode:
fast charging. If either of these limits is ex-
If temperature is too high, battery charging
ceeded, fast charge action is terminated.
is regarded as completed. If temperature is
too low, function of ∆T / ∆t detection is
disabled, just as thermistor is not existing.
Trickle Charge
There are five different selectable duty cycles
for trickle charge after the fast charge to prevent
the loss of charge due to battery selfdischarging. The setting of SEL1 and SEL2 pins
controls the duty cycle. This function can only
be activated on the following three situation:
Battery pack A is charge full and battery
pack B is abnormal.
Battery pack B is charge full and battery
pack A is abnormal.
Battery pack A and B are both charge full.
(c)
V cc - 0.4V>SEL3 >1.4V
2
Acceptable ABV/BBV Range:
Before initial timer: 0.16V~2 V
After initial timer:1.2V~2V
Temperature Protection Mode:
Entering charge-suspending mode when
temperature is either too low or too high,
same as abnormal battery voltage. Latch
for charge-suspending function is provided
DESIGN GUIDE
ABV/BBV Range and Temperature Protection
for high temperature protection, but not for
low temperature protection.
15
AIC1782
(d) 0.3V> SEL3
Acceptable ABV/BBV Range:
Before initial timer: 0.16V~2 V
After initial timer:1.2V~2V
Temperature Protection Mode:
For SEL3 < (VCC/2) -0.4V, the suggested divider
resistances of RA and RB for the corresponding
number of battery cells are as below:
If temperature is too high, battery charging
BATTERY
CELLS
RA/RB
RA(KΩ)
RB (KΩ)
is regarded as completed. If temperature is
2
1
240
240
too low, function of ∆T / ∆t detection is
disabled, just as thermistor is not existing.
3
2
240
120
4
3
240
80
5
4
300
75
6
5
300
60
8
7
360
51
Battery Voltage Measurement
The AIC1782 measures the battery voltage
through ABV and BBV pins, which is connected
to battery positive terminal through a resistordivider network, as shown in Fig. 2. The ac-
10
9
360
40
12
11
390
36
16
15
410
27
ceptable limit of divided battery voltage is determined by the input voltage of SEL3 pin.
Battery Temperature Measurement
The AIC1782 employs a negative temperature
VBAT
coefficient (NTC) thermistor to measure the
RA
’
R6
ABV/BBV
C6
AIC1782
0.1µF
100K
4.7µF
RB
+
C5
battery s temperature. The thermistor is inherently nonlinear with respect to temperature. To
reduce the effect of nonlinearity, a resistordivider network in parallel with the thermistor is
recommended. A typical application circuit is
Fig. 2 Battery Voltage Divider
shown in Fig. 3.
VCC
BATTERY
CELLS
RA/RB
RA (KΩ)
RB (KΩ)
2~4
2
240
120
3~6
3.3
300
91
4~8
4.9
300
62
5~10
6.4
300
47
6~12
7.8
310
39
8~16
10.8
390
36
Thermistor
sponding number of battery cells are as below:
5
VCC
Rx
vider resistances of RA and RB for the corre-
ATS/BTS
C7
0.1µF
For SEL3 > (VCC/2) + 0.4V, the suggested di-
VBAT
AIC1782
Ry
16
GND
Fig. 3 Battery Temperature Sense Circuit
with a Negative Temperature Coefficient (NTC) Thermistor
16
AIC1782
The calculation for Rx and Ry in the circuit is as
67
5.5
29.5
following.
68
5.3
27.5
Ry / /RTH
0.29 Vcc =
× Vcc
Rx + (Ry / / RTH)
RTH= The resistance of thermistor at upper limit
of temperature protection.
Ry / /RTH
0.72 Vcc =
× Vcc
Rx + (Ry / / RTL)
RTL= The resistance of thermistor at lower limit
of temperature protection.
69
5.2
25.8
70
5.0
24.3
TABLE. 2 Values of Rx and Ry at TL = -10°C
TH (°C)
Rx (KΩ)
Ry (KΩ)
45
11.4
95.6
46
11.0
85.0
47
10.6
76.2
48
10.2
68.9
49
9.8
62.8
50
9.5
57.5
51
9.1
52.9
52
8.8
48.8
53
8.5
45.3
If temperature characteristic of the thermistor
is like that of SEMITEC 103AT-2, the resistance of Rx and Ry is tabulated for different
TL and TH as below.
54
8.2
42.1
55
7.9
39.4
56
7.6
36.8
57
7.4
34.6
(note: TL is lower temperature limit and TH is
upper temperature limit.)
58
7.1
32.5
59
6.9
30.7
60
6.7
29.0
61
6.4
27.4
62
6.2
26.0
63
6.0
24.6
64
5.8
23.4
65
5.6
22.2
Substitution and rearranging the equations yield
Rx= 2.061 ×
Ry =
RTL × RTH
RTL − RTH
5. 3 × RTL × RTH
RTL − 6. 3RTH
TABLE. 1 Values of Rx and Ry at TL = 0°C
TH (°C)
50
51
52
53
54
55
56
Rx(KΩ)
10.1
9.7
9.4
9.0
8.7
8.4
Ry (KΩ)
551.1
300.7
204.8
153.9
122.8
101.8
8.1
86.5
57
7.8
75.0
58
7.5
66.0
59
7.2
58.7
The calculation of ADJ pin voltage is shown in
60
7.0
52.8
the following procedure followed by an example.
61
6.8
47.8
62
6.5
43.6
63
6.3
39.9
64
6.1
36.8
65
5.9
34.0
66
5.7
31.6
Setting the ADJ Pin Voltage
The slope of ∆T / ∆t detection is determined by
ADJ pin voltage of the AIC1782.
Procedure
(a) First, determine the temperature protection
limits TH and TL. Then, substitute TH & TL
into the following equation:
17
AIC1782
∆V TS
0.72V CC − 0.29V CC 0.43V CC
=
=
∆TBASE
TH − TL
TH − TL
TABLE. 3 ADJ Pin Voltage (TL=0°C, TH=50°C)
S.T.
(b) Determine the safety timer to obtain the
value of ∆tBASE .
56(sec. )
∆t BASE(sec.) =
× Safety Timer (min. )
80(min. )
(c) Determine the expected slope of ∆T / ∆t at
which temperature rises y°C in x seconds
and fast charge is subsequently cut off.
∆T y
=
∆t
x
(d) Calculate the value of VADJ
∆V TS
∆T
V ADJ = 25 ×
×
× ∆t BASE
∆TBASE ∆t
Example
∆T / ∆t
40 min. (2C)
80 min. (1C)
120 min. (0.67C)
0.75
1.0
1.25
(°C/min.) (°C/min.) (°C/min.)
0.37
0.5
0.63
0.75
1.0
1.25
1.12
1.5
1.87
1.5
2.0
2.5
1.87
2.5
3.12
2.25
3.0
3.75
160 min. (0.5C)
200 min. (0.4C)
240 min. (0.33C)
A similar table for temperature range from 0°C
to 60°C is as below.
TABLE. 4
TH=60°C)
S.T.
ADJ Pin Voltage (TL=0°C,
∆T / ∆t
0.75
1.0
1.25
(°C/min.) (°C/min.) (°C/min.)
40 min. (2C)
0.31
0.42
0.52
80 min. (1C)
0.62
0.84
1.05
120 min. (0.67C)
0.94
1.25
1.56
∆TBASE
50 − 0
which means that VTS decreases 43mV
as temperature rises 1°C.
160 min. (0.5C)
1.25
1.67
2.08
200 min. (0.4C)
1.56
2.08
2.60
(b) If safety timer is equal to 80 minutes, ∆tBASE
240 min. (0.33C)
1.87
2.5
3.12
(a) Let TH=50°C, TL=0°C, VCC =5V. We have
∆V TS
=
0. 43 × 5
= 0. 043 V / ° C
is then 56 seconds.
(c) If fast charge should be terminated when
temperature rises 1°C in 60 seconds, then
Setting the Period of Safety Timer
The AIC1782 provides a method for linearly
1
= 0. 0166
60
adjusting the period of safety timer with an ex-
(d) VADJ =25 x 0.043 x 0.0166 x 56 = 1(V)
The relation between safety timer length and
∆T / ∆ t =
If the temperature range is from 0°C to
50°C, the voltage of VADJ under different
setting conditions should be set as tabulated below.
ternal resistor connected from TMR pin to GND.
the external resistor (RTMR) is shown in Fig. 4.
The table following shows the resistor values for
some of the commonly chosen safety timer periods. Also shown in the table is their corresponding oscillator frequencies.
18
AIC1782
ABLE. 5 The Operating Mode of AIC1782
800
RTMR (KΩ)
600
MODE pin
Mode
Function
VCC
Test
Safety timer period
scaled down to 1/32....
etc.
Floating
Normal Normal operation
GND
AC
400
200
0
–∆V detection disabled
The Mode of LED Display and Trickle Charge
0
100
200
300
400
500
Safety Timer (min.)
Fig. 4 Safety Timer vs RTMR
The AIC1782 provides two LED display modes
and five pulsed trickle charge modes. The
modes of LED display and trickle charge are
RTMR
(KΩ)
11
23
48
74
100
152
206
314
491
667
Osc.Freq.
(KHz)
262.4
131.2
65.6
43.7
32.8
21.9
16.4
10.9
7.3
5.5
Safety timer
(min.)
10
20
40
60
80
120
160
240
360
480
Selecting Mode of Operation
The AIC1782 provides three modes of opera-
tion: normal, test, and AC mode, determined by
the setting of MODE pin according to TABLE 5.
The AIC1782 will operate normally when the
MODE pin is left floating (a 0.1µF capacitor is
recommended to be tied to MODE pin if the
determined by the tri-level inputs, SEL1 and
SEL2 pins, as in the TABLE 6.
TABLE.
Charge
SEL1
VCC
Floating
GND
6 Mode of LED Display and Trickle
SEL2
Trickle
Charge
LED
Duty
Display
Mode
VCC
N/A
Type 1
Floating
1/32
Type 1
GND
1/64
Type 1
VCC
1/128
Type 1
Floating
1/256
Type 1
GND
N/A
Type 2
VCC
1/32
Type 2
Floating
1/64
Type 2
GND
1/128
Type 2
Displaying the Battery Charging Status
charge circuit works in a noisy environment).
The AIC1782 provides four open-drained outputs,
When the MODE pin is biased to GND, the
in which LEA1 and LEA2 are used to indicate the
function of − ∆V detection is disabled. When
the MODE pin is biased to VCC, the AIC1782
enters the test mode. The test mode can be
used to significantly reduce production test time.
For relevant informations please contact AIC directly.
battery charging status of pack A, yet LEB1 and
LEB2 are used to indicate battery charging status
of pack B. Refer to the table of LED display mode
(TABLE 6), depending on the setting of SEL1 and
SEL2 pins, the outputs of LEA1, LEA2, LEB1, and
LEB2 pins are shown in the following table:
19
AIC1782
TYPE 1
LEA1/
Power
On
Wait
Charge
Full
Abnormal
1HZ
ON
ON
OFF
OFF
LEB1
LEA2/
Power Wait
Fast
Charge
Fault
ON
ON Charging Completed Conditions
ICOA/
ON
ICOB
OFF
ON
OFF
ON
ON
OFF
See pin 14
& 15
ON
OFF
LEB2
Test Mode
TYPE 2
LEA1/
Power
On
Wait
Charge
Full
Abnormal
1HZ
1HZ
ON
OFF
4HZ
controlled ADJ, ABV, BBV, ATS, BTS, SEL1 and
SEL2 pin voltages of a recommended AIC1782
test scheme, utilizing TEST mode function. Out-
LEB1
LEA2/
Fig. 5 shows the timing diagram for externally
1HZ
1HZ
4HZ
ON
OFF
LEB2
put waveforms of LEA1, LEA2, LEB1, LEB2,
ICOA and ICOB of a properly functioning
AIC1782 are also shown in the figure. For detailed information please consult with AIC staffs
Charging Current Control
directly.
As shown in the typical application circuit, the
AIC1782 offers two open-drained output pins,
ICOA and ICOB pins, to control the charging current of battery pack A and pack B. When fast
charge is completed, the AIC1782 enters the
trickle charge mode. In trickle charge mode, the
ICOA or ICOB pins output switch with predetermined duty cycle. Refer to the table of trickle
charge mode (TABLE 6), the duty cycle is determined by the setting of SEL1 and SEL2 pins. The
following table summarizes how ICOA and ICOB
pins correspond to various charging states.
20
AIC1782
TIMING DIAGRAM
VCC, SEL3, MODE=5V, (DSW FREQ.=820KHz, 25 TIMES of 32.8K)
Power Init. PEAK TIMER TEST
ON
-∆V TEST
5V
ADJ
SAFETY TIMER TEST
∆T/∆t TEST
-∆V DISALBE TEST
1.12V
3V
<2.1V
(-0.15%)
1.95V
2V
(A):ABV
(B):BBV
2V
1.997V
1.9V
1.5V
(A):ATS
(B):BTS
2V
2V (-0.15%)
1.997V
1.997V
1.993V
(-0.35%)
4V
4V
4V
2V
2V
1.96V
0V
ON
ON
OFF
ON
OFF
OFF
ON
SEL1
SEL2
Floating
Floating
VCC
Floating
0.1
0.14 0.12
1
0.74
2
0 0.14 0.26
6.01
ON
3.2KHz
ON
(A):ICOA
(B):ICOB
OFF
OFF
ON
OFF
(A):LEA2
(B):LEB2
2V
2mV
Step/100mS
(-2.5%)
OFF
ON
(A):LEA1
(B):LEB1
TIME (B)
(SEC.)
STAGE
1.85V
(-2.15%)
OFF
4V
<2.1V
2V
TIME (A)
(SEC.)
STAGE
2mV
Step/100mS
0.1
0.14 0.12
11
12
6.11 6.25 6.37
0.26
0.12
3
4
1
0.74
1.26 1.38
0.32
1.17
Floating
GND
0.32
0.12
5
6
0.32
0.97
0.5
0.24
7
2.02 2.14
0.26
Delay 0.3
13
14
7.21 7.47
GND
Floating
2.46
3.43
0.4
1.32
8
9
3.93 4.17
0.5
0.24
15
7.77
GND
GND
4.57
Floating
Floating
0.1
0.02
10
5.89
5.99
6.01
0.4
16
8.27 8.51
8.91
Fig. 5 Timing Diagram of AIC1782 in Test Mode
21
AIC1782
PHYSICAL DIMENSIONS
20 LEAD PLASTIC DIP (unit: mm)
D
SYMBOL
MIN
MAX
A1
0.381
—
A2
2.92
4.96
b
0.35
0.56
C
0.20
0.36
D
24.89
26.93
E
7.62
8.26
E1
6.09
7.12
E1
E
A1
A
C
L
e
eB
e
b
2.54(TYP)
eB
—
10.92
L
2.92
3.81
20 LEAD PLASTIC SO (300 mil) (unit: mm)
D
H
E
e
B
SYMBOL
MIN
MAX
A
2.35
2.65
A1
0.10
0.30
B
0.33
0.51
C
0.23
0.32
D
12.60
13.00
E
7.40
7.60
e
A
A1
C
L
1.27(TYP)
H
10.00
10.65
L
0.40
1.27
22
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