AD AIC1761

AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
FEATURES
Reliable Fast Charge Control of NiMH/NiCd Batteries.
Quick and Easy Testing for Production.
Fast Charge Termination by:
1. Accurate -∆V Detection Level with Respect to
Peak Battery Voltage Value.
AIC1761 ................……………........ -1%
AIC1766 ............…………..……...... -0.25%
2. Peak Voltage Timer (0∆V).
Adjustable Fast Charge Safety Timer.
Protection against Temperature Fault.
Protection against Short-Circuited and Open Batteries.
Wide Operation Voltage Range: 9V to 18V, no Extra Regulator Needed.
Large Battery Voltage Detection Range: 0.65V to
3.7V.
LED Drivers to Indicate Charge Status or Fault
Conditions.
Voltage Reference Output.
Space-Saving Packages:
8-PIN DIP, SO
14-PIN DIP, SO
APPLICATIONS
Battery Chargers for :
Mobile Phones
Notebook and Laptop Personal Computers
Portable Power Tools and Toys
Portable Communication Equipments
Portable Video and Stereo Equipments
DESCRIPTION
The AIC1761/1766 fast charge controller IC is
designed for intelligent charging of NiMH or NiCd
batteries without overcharging. It detects a voltage
drop (-∆V) occurring in the final stage of a fast
charging cycle and correspondingly controls the
charging current. Fast charge can also be cut off
by a peak voltage timer (0∆V).
The detection of -∆V is a very reliable method to
terminate fast charging for NiMH and NiCd batteries. The AIC1761/1766 uses -∆V detection as one
of primary decisions for fast charge cut-off. The ∆V value for the AIC1761 is as small as 16mV per
cell,
suitable
for
NiCd
batteries.
The
-∆V value for the AIC1766 is as small as 4mV per
cell, particularly suitable for NiMH as well as the
NiCd batteries. The peak voltage timer is particularly useful when the voltage drop at the end of
charge for some batteries, e.g. NiMH cells, is not
pronounced enough for reliable detection. An adjustable safety timer (3 settings) is used as a backup termination method. Provisions are made with
the AIC1761/1766 to prevent fast charge under
temperature fault conditions. Two LED outputs are
used to indicate the charging status. Another flash
LED output can be used alone to indicate charge
status.
AC mode allows the battery to drive its loads while
being charged. Test mode is provided to dramatically reduce production test time.
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1
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
TYPICAL APPLICATION CIRCUIT
VIN
R8
470
12 ~ 15 V
C1
10µF
+
R1
120
0.5W
L1
220µH
+
C2
470pF
BST
SC
8
D2
1N5819
C4
IS
3 TC
VCC
6
FB
5
C7
LED1
RED
100µF
BATTERY
3 ~ 5 CELLS
1K
R9
1K
0.33Ω
1W
220µF
R3
100K
R7
150K
7
2 SE
4 GND
C3
1µF +
D4
1N5819
*RS
+
ZD1
9.1V
R5
D1
1N4148
1
D3
1N4148
R2
1K
C6
0.1µF
R4
51K
VREF
2 GND
VDD
7
C5
3 TIMER
VOUT 6
4 MODE
LED 5
AIC1563
R10
1K
8
4.7µF
+
*Fast Charge Current= (0.3/RS) A
1 VBT
LED2
GREEN
AIC1761/66
Simple Battery Charger for NiMH / NiCd Battery
ORDERING INFORMATION
AIC176X-XXXX
PIN CONFIGURATION
ORDER NUMBER
VERSION
08: 8 PIN VERSION
14: 14 PIN VERSION
PACKAGE TYPE
N: PLASTIC DIP
S: SMALL OUTLINE
TEMPERATURE RANGE
C=0°C~70°C
-∆V DETECTION LEVEL
1: -1%
6: -0.25%
AIC1761-CN08
AIC1766-CN08
(PLASTIC DIP)
TOP VIEW
AIC1761-CS08
AIC1766-CS08
(PLASTIC SO)
AIC1761-CN14
AIC1766-CN14
(PLASTIC DIP)
VBT
1
8
VREF
GND
2
7
VDD
TIMER
3
6
VOUT
MODE
4
5
LED
TOP VIEW
AIC1761-CS14
AIC1766-CS14
(PLASTIC SO)
GND
1
14 GND
TIMER
2
13 NC
MODE
3
12 VBT
LED
4
11 NC
VOUT
5
10 VREF
NC
6
9
VNTC
FLASH
7
8
VDD
ABSOLUTE MAXIMUM RATINGS
Supply Voltage
.......................…………….......................................................................... 18V
DC Voltage Applied on any Pin
..............................................…………….............................. 18V
Sink Current of VOUT Pin, LED Pin, and FLASH Pin
Operating Temperature Range
...............................…………….........20mA
...........................................…………........................ 0°C to 70°C
Storage Temperature Range ..............................................……………................. -65°C to 150°C
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TEL: (8863)577-2500 FAX:(8863)577-2510
2
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
TEST CIRCUIT
-
150K
R2
4.7µF
C1
Voltage
Source
+
+VDD
150K
R3
VDD
VBT
+
0.1µF
C2
0.1µF
C3
+
100µF
C4
390K
R1
VOUT
GND
1.5K
R6
LED
+VDD
TIMER
1.5K
R7
FLASH
VREF
20K
R5
4.7K
R4
1.5K
R8
MODE
VNTC
ELECTRICAL CHARACTERISTICS (VDD=12.5V, Ta=25°°C, unless otherwise specified.)
PARAMETER
TEST CONDITIONS SYMBO
L
Supply Voltage
VDD
Supply Current
IDD
MIN.
TYP.
MAX.
UNIT
18
V
1.5
mA
9
-∆V Detection Level w.r.t.* Peak
Value
AIC1761
-1
%
AIC1766
-0.25
%
Voltage Protection Limits
Battery Low
VBT
Battery High
0.5
0.65
0.8
V
3.5
3.7
3.9
V
Input Impedance of TIMER Pin
ZTIMER
100
KΩ
Input Impedance of MODE Pin
ZMODE
100
KΩ
RLED
1
MΩ
Output Resistance of LED Pin
Fast Charge
Trickle Charge
Output Resistance of VOUT Pin
Fast Charge
RVOUT
25
Ω
25
Ω
MΩ
1
Trickle Charge
FLASH pin
Output Resistance
Fast Charge
RFLASH
25
Ω
Frequency
Trickle Charge
FFLASH
1
Hz
DFLASH
50
%
VREF
5.85
V
Duty Cycle
Reference Voltage
IREF
1.5
Under-Temperature
αNTCL
0.60
0.7
0.80
VREF
Over-Temperature
αNTCH
0.15
0.2
0.25
VREF
Reference Source Current
Temperature Fault Voltage
Limits as Fraction of VREF
mA
*w.r.t.: with respect to
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3
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
TYPICAL PERFORMANCE CHARACTERISTICS
Output Resistance of VOUT pin vs Power
Supply Voltage (Fast Charge Mode)
32
28
28
RLED (Ω)
RVOUT (Ω)
32
Output Resistance of LED pin vs Power
Supply Voltage (Trickle Charge Mode)
24
24
20
20
11
9
13
15
17
18
9
11
13
VDD(V)
18
Output Resistance of VOUT pin vs
Temperature (Fast Charge Cycle)
32
34
28
30
RVOUT (Ω)
RFLASH (Ω)
17
VDD(V)
Output Resistance of FLASH pin vs Power
Supply Voltage (Fast Charge Mode)
24
20
15
26
9
11
13
15
17
22
18
0
20
VDD(V)
Output Resistance of LED pin vs Temperature
(Trickle Charge Cycle)
6.0
VREF (V)
30
RLED (V)
6.2
26
22
40
80
5.8
5.6
20
60
VREF Reference Voltage vs Temperature
34
0
40
Temperature (°C)
60
80
0
20
40
60
80
Temperature (°C)
Temperature (°C)
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TEL: (8863)577-2500 FAX:(8863)577-2510
4
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
TYPICAL PERFORMANCE CHARACTERISTICS (CONTINUED)
VBT (Low) Limit vs Temperature
3.8
0.71
3.7
0.67
VBT (V)
VBT (V)
VBT (High) Limit vs Temperature
3.6
0.63
0.59
3.5
(V)
3.4
0
20
40
60
0.55
80
0
20
40
60
80
Temperature (°C)
Temperature (°C)
Safety Timer vs Temperature
(MODE pin = VDD)
Safety Timer (min.)
45
43
41
39
37
35
0
20
40
60
80
Temperature (°C)
BLOCK DIAGRAM
VREF
VNTC (for 14 pin version)
VR4
VR3
VDD
Voltage
Regulator
+
-
+
LED
Power On
Reset
-
GND
VR1
FLASH
(for 14 pin version)
+
-
CHARGE CONTROL
VBT
VR2
VOUT
STATE MACHINE
+
-
13-Bit
ADC
Timing
Control
Mode
Select
MODE
Oscillator
TIMER
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TEL: (8863)577-2500 FAX:(8863)577-2510
5
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
PIN DESCRIPTIONS
VDD PIN
-
Supply voltage input.
LED PIN
GND PIN
-
Ground.
VOUT PIN - Output, for LED indicator.
VBT PIN
-
Input, to sense battery voltage.
FLASH PIN - Output, for LED indicator.
MODE PIN -
Input, to set IC operation mode.
TIMER PIN -
Input, for safety timer control.
VREF PIN
Voltage reference output.
-
- Output, for LED indicator.
(Available for 14-pin version only.)
VNTC PIN
- Input, for temperature protection.
(Available for 14-pin version only.)
APPLICATION INFORMATIONS
BATTERY PROPERTIES
The basic principle of rechargeable battery systems, including NiMH and NiCd cells, is that the
processes of charge and discharge are reversible.
The charge characteristics of NiMH and NiCd
cells look similar in that (1) the cell voltage at the
end of charge drops and (2) the cell temperature
increases rapidly near the end of charge. Fig. 1
shows the charge voltage and charge temperature characteristics of NiMH and NiCd cells. Notice that the cell voltage decline of NiMH cells at
the end of charge is less pronounced than for
NiCd cells.
1.7
1.5
60
Voltage
1.4
50
1.3
40
NiMH
Temperature
NiCd
1.2
1.1
0
20
40
60
80
100
30
Cell Temperature (°C)
Cell Voltage (V)
70
NiMH
NiCd
20
Time (min.)
Fig. 1
Typical
Charge
NiMH/NiCd Battery
Characteristics
Negative delta voltage cutoff (-∆V).
Peak voltage timer cutoff (0∆V).
Maximum temperature cutoff (TCO).
Maximum voltage cutoff (VCO).
Safety timer cutoff.
The principle of operation of the AIC1761/1766 is
described in the following section.
THE AIC1761/1766 OPERATION
80
Charge Current=1C
1.6
The AIC1761/1766 is a battery fast charge controller IC that utilizes the following methods to
terminate the fast charge process for NiMH or
NiCd battery cells:
of
Fast-charge batteries are available where recharging takes for only 1 hour or less with a simple control circuit. One main purpose of the control circuit is to terminate the fast-charge process
to prevent the temperature and internal pressure
of the battery cell from building up to a damaging
level which degrades or even destroys the battery
cell.
When power is first applied to the charge system,
consisting of rechargeable battery cells, charge current source, the AIC1761/1766 and its associated
external circuit, all internal digital circuit blocks of
the AIC1761/1766 are reset by internal power-onreset circuitry. The internal control unit then checks
the battery condition to prevent fast charge from
taking place under battery fault conditions, i.e. cell
voltage fault (VBT<0.65V or VBT>3.7V) or cell temperature fault (αNTC>αNTCL or αNTC<αNTCH, for
the 14-pin version). Temperature fault limits corresponding to αNTCL and αNTCH are determined by
an external thermistor divider circuit as included in
the Application Examples, Fig. 10. After the battery
passes condition fault checks, VOUT pin goes to
low to start fast charge while initial timer and safety
timer of the AIC1761/1766 start counting. Both the
negative delta voltage detector and the peak voltage
timer, however, are disabled until the initial timer
period in the initial stage of a charge circle elapses.
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TEL: (8863)577-2500 FAX:(8863)577-2510
6
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
The AIC1761/1766 constantly monitors the voltage
at VBT pin, which rises as battery cells are being
fast-charged till battery full condition is nearly approached. The battery temperature is also constantly being sensed to guard against abnormal
temperature situations. VOUT pin will be pulled high
by an external pull-up device and the fast charge
process be switched to trickle charge when one of
the following situations is encountered:
The battery voltage stays at its peak value for
the duration determined by the peak voltage
timer setting (0∆V).
The VBT pin voltage exceeds the “high” battery
voltage protection limit (VCO).
If
0.65V<VBT<3.7V
NO
YES
-∆V detector &
peak voltage timer
start working after
initial period ends.
-∆V detector &
peak voltage timer
working.
If
αNTCL>αNTC
& αNTC>αNTCH
NO
YES
If
0.65V<VBT<3.7V
The selected safety timer period has finished.
YES
TIMER PIN
VOUT goes high
for trickle
charge, -∆V
detector reset,
safety timer
stops.
VOUT goes high
for trickle charge,
NO Safety Timer and
-∆V Detector
reset
If
safety timer period
has finished.
The TIMER pin can be used as follows to select
one of the preset safety timer period and its corresponding periods of initial timer and peak voltage timer:
YES
NO
NO
Safety
Timer
VOUT goes high for
trickle charge ,
-∆V detector reset,
safety timer stops.
If
αNTCL>αNTC
& αNTC>αNTCH
The battery temperature, sensed by the thermistor divider, exceeds the fault temperature
range (TCO).
TIMER
Pin
VOUT goes high for
trickle charge,
safety timer and
NO -∆V detector reset.
YES
VOUT goes low for
fast charge,
safety timer starts
counting.
A negative delta voltage (-∆V) at VBT pin is detected when compared to its peak value. The
sampling rate of -∆V detection is 2seconds/
sample. The detection level of -∆V is -1% for the
AIC1761 and -0.25% for the AIC1766.
Power ON
If
-∆V decline of VBT
is detected.
NO
If
peak voltage timer
period has finished.
YES
Peak Volt- Initial Timer
age Timer
VDD
40
min.
2 min.
1.5 min.
GND
80
min.
4 min.
3.0 min.
Floating
160 min.
8 min.
3.0 min.
YES
VOUT goes to high, fast charge finished, and trickle charge start.
Fig. 2 Operation Chart of the AIC1761/1766
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AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
MODE PIN
1. Safety timer reduced by 512 times.
The MODE pin determines the mode in which the
IC works:
2. Initial timer reduced by 512 times.
MODE
Pin
Mode
Floating
NORMAL
Normal operation
VDD
TEST
1/512 safety timer
GND
AC
−∆V detector reset,
timer stops (not reset)
3. Peak timer reduced by 64 times.
Function
The AIC1761/1766 will operate normally when the
MODE pin is left floating ( a 0.1µF capacitor is recommended to be tied to MODE pin if the charge
circuit works in a noisy environment). The
AIC1761/1766 otherwise works in following ways
if the MODE pin is biased either to VDD or to GND:
(A) AC Mode (MODE pin biased to GND)
In the midst of normal charge operation, where
VBT pin voltage is in the range from 0.8V to 3.5V
and the preset safety timer has not run out, the
safety timer will stop if the MODE pin is somehow
pulled down to GND level. As long as the MODE
pin remains low, the VOUT pin stays ON and
LED pin OFF regardless whether the battery pack
voltage declines (-∆V present) or not.
The AC mode can be activated by pulling MODE
pin to GND to avoid premature battery charge
cutoff due to fluctuating charge current source.
Switching MODE pin after the end of the safety
timer has no effect on the AIC1761/1766 display
outputs, i.e., VOUT pin stays OFF while LED pin
stays ON.
One critical requirement needs to be observed for
-∆V detector of the AIC1761/1766 to work properly in TEST mode. That is, VBT pin voltage must
be kept between approximately 2.8V to 3.3V,
rather than 0.8V to 3.5V in NORMAL mode.
If the TEST mode function is to be utilized in production test, it has to be well planned and included in circuit design phase to make the voltages of
VBT pin and MODE pin externally controllable. In
addition, an externally controllable TIMER pin can
further reduce test time required for testing the
AIC1761/1766 in TEST mode.
Fig. 3 shows the timing diagram for externally
controlled VBT, TIMER, and MODE pin voltages
of a recommended AIC1766 charge circuit production test scheme, utilizing TEST mode function. Output waveforms of VOUT and LED pins
(and FLASH pin for 14 pin version) of a properly
functioning AIC1766 are also shown in the figure.
In timer segments 4, 8 and 10, VOUT pin should
change from ON to OFF, LED pin from OFF to
ON, and FLASH pin from ON to flashing output
(approximately 4 Hz). For the reset of time,
VOUT pin should remain ON, LED pin OFF, and
FLASH pin ON.
(B) TEST Mode (MODE pin biased to VDD)
An unique feature of the AIC1761/1766 is that it
can be put into a TEST mode by pulling the
MODE pin to VDD, allowing verification tests for
the AIC1761/1766 charge circuit to be performed
in a few tens of seconds, extremely valuable in final phase of production.
When the AIC1761/1766 is in TEST mode, all the
internal timers are reduced by the following factors when compared to normal operation:
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8
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
Init. VBT
Timer Set
Up
TIMER
Pin
AC
Mode
VBT
Set Up
AC
Mode
-∆V Test
(min. 3.75S)
Safety Timer Test
VDD/2
VDD
GND
MODE
Pin
VDD
3V
VBT
Pin
Peak Timer Test
(min.1.875S)
GND
GND
3V
2.995V
2.98V
2.995V
*2.988V
2.8V
OFF
VOUT
Pin
ON
LED
Pin
OFF
ON
FLASH
Pin
*
ON
4.27Hz
TIME
0.5S
0.4S
1.5S
1.5S
20mS
0.4S
4.7S
1.5S
20mS
2.5S
0.5S
Section
1
2
3
4
5
6
7
8
9
10
11
2.972V for the AIC1761
Fig. 3
Timing Diagram of AIC1766 in Test Mode
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9
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
R14+R13 must be greater than 535KΩ if R15 is
150KΩ (refer to Fig. 4). When the battery pack is
disconnected from the charging circuitry the VBT
pin voltage must be higher than 4.0V, dictating
VBAT node voltage of the charging circuitry to be
higher than 18.3V (4V x 4.57). Practically, however,
the charging circuit supply voltage +VIN should be
higher than 18.5V in order to ensure proper operation. In the case that supply voltage +VIN can
not meet this requirement, application circuit of Fig.
4 can be adopted to get around this problem.
The LED indicators work as the following table:
LED
PIN
VOUT
PIN
FLASH
PIN
Fast Charge
OFF
ON
ON
Trickle
Charge
ON
OFF
FLASH
VBT
Abnormal
OFF
OFF
OFF
LED pin is used in conjunction with VOUT pin
while FLASH pin works alone.
+VIN
Referring to the APPLICATION EXAMPLES (Fig.
10), the temperature limits beyond where the fast
charge is prohibited can be set by choosing values
for resistors and the thermistor of the thermistor
divider according to the following formula:
27K
VBAT
9012
Q2
R2
150K
R13
270K
9012
Q1
R18 = 3.57 RT1 RT2/ (RT1 - RT2)
R3
R19 = 10 RT1 RT2 / (1.218 RT1 - 11.2 RT2)
RT1 : Thermistor resistance at low temperature
limit.
RT2 : Thermistor resistance at high temperature
limit.
BATTERY VOLTAGE DIVIDER
To ensure proper operation of the AIC1761/1766,
selection of resistor values for battery voltage divider must meet the following two crucial requirements:
1. When the battery pack is disconnected from
the charge circuitry, the voltage of VBT pin
must be higher than 4.0V or lower than 0.5 V to
put the AIC1761/1766 in reset status, where
VOUT and LED pins become high impedance
and FLASH pin (only for 14 pin version) goes to
high level.
R14
0.1µF
C1
R7
R5
270K
VBT
150K
+
0.1µF
C3
150K
R15
4.7µF
C2
GND
Fig. 4 Battery Voltage can be Raised to VIN - 0.9V
when being Charged.
CHARGER CIRCUIT DESIGN TIPS
1.
A stable constant charge current is crucial for
reliable precision −∆V detection by the
AIC1761/1766 since fluctuation of the charge
current can cause fluctuation of the battery
terminal voltage due to battery internal series
resistance, which will likely result in errors
−∆V detection by a properly functioning
AIC1761/1766.
2.
To prevent the AIC1761/1766 from overvoltage damage, make sure that none of
AIC1761/1766 pins sees any voltage beyond
the supply voltage, which needs to be between +9V and +18V.
2. When the battery pack is connected in normal
operation, the VBT pin voltage must remain in
the range of 0.8V to 3.5V even when the battery pack voltage reaches to its peak when
near full charge.
Take charging a 8-cell battery pack as an example.
The highest voltage would be 16V when fully
charged if the highest voltage of a fully charged
battery cell is assumed to be 2V. Since the VBT
pin voltage is restricted to be no higher than 3.5V,
the battery voltage divider ratio must be higher
than 3.57 (16V/3.5V -1). In other words, resistor
390K
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TEL: (8863)577-2500 FAX:(8863)577-2510
10
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
Since the AIC1761/1766 is fabricated with
CMOS process, cares must be taken in handling this device to avoid possible damage
from electro-static discharge.
Charge Current=0.7A
Cell Capacity=700mAH
50
1.6
Voltage
40
1.5
Temperature
30
1.4
AIC1766
1.3
0
20
40
60
Cell Temperature(°C)
5.
Critical components need to meet adequate
rating to prevent heating-up of these components from causing circuit malfunction.
60
1.7
20
80
Charge Time (min.)
EXPERIMENTAL RESULTS
Fig. 6 Charge Characteristics of NiCd Battery
60
1.6
Charge Current = 1A
Cell Capacity =1000mAH
1.5
50
Cell Voltage(V)
Experiments have been conducted to verify the
AIC1761/1766 operation with NiCd and NiMH
battery cells of various brands. Actual results
shown in the following figures clearly indicate that
the negative delta voltage detector and the peak
voltage timer of the AIC1761/1766 have precisely
detected the tiny cell voltage drops or the cell voltage peaks and subsequently terminated the fast
charge process after batteries are fully charged.
The battery cell temperatures were all under
safety levels. Note that the fast charge for the
NiMH battery in Fig. 5 is terminated by the peak
voltage timer (0 ∆V ) while the fast charge for the
NiCd battery in Fig. 6 is terminated by the -∆V
detector.
Voltage
40
1.4
Temperature
1.3
30
Cell Temperature(°C)
4.
If the battery charge current is high, say, over
1.5A, quality of circuit board layout and wiring
connection points become increasingly important in the charger circuit reliability.
Cell Voltage (V)
3.
AIC1761
1.2
0
10
20
30
40
50
60
20
70
Charge Time (min.)
Fig. 7 Charge Characteristics of NiMH Battery
1.6
Cell Voltage (V)
Voltage
40
1.4
Temperature
30
1.3
AIC1766
20
1.2 0
20
40
60
1.7
60
Charge Current=0.7A
Cell Capacity=700mAH
50
1.6
Voltage
40
1.5
30
1.4
AIC1761
80
Charge Time (min.)
Temperature
1.3
Fig. 5 Charge Characteristics of NiMH Battery
Cell Temperature(°C)
50
Cell Voltage(V)
AIC1766
1.5
Cell Temperature(°C)
60
Charge Current = 1A
Cell Capacity = 1000mAH
20
0
20
40
60
80
Charge Time (min.)
Fig. 8 Charge Characteristics of NiCd Battery
Both Fig. 5 and Fig. 6 were obtained by using the
AIC1766. Results of similar experiments by using the
AIC1761 are shown in Fig. 7 and Fig.8.
ANALOG INTEGRATIONS CORPORATION
www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
11
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
APPLICATION EXAMPLES
R8
+VIN
12~28 V
D1
1N4148
+
C1
220µF
35V
1
SC
BST
SE
IS
2
3
TC
VCC
4
C2
1nF
GND
FB
8
D3
1N4148
R2
1.2K
R1
2K
*L1
220µH
C3
4.7µF +
50V
D4
1N5819
**RS
+
D2
1N5819
470
C4
220µF
35V
0.33Ω
1W
R4
1K
R6
51K
R7
150K
+
C5
4.7µF
C6
0.1µF
1
2
3
4
5
*L1=MPP Core or Iron Powder Core
**Fast Charge Current:(0.3/RS)A
LED1
RED
LED2
GREEN
R9
1K
6
AIC1563
C7
100µF
# BATTERY
R5
100K
7
+
ZD1
9.1V
VBT
VREF
GND
VDD
TIMER VOUT
LED
MODE
# 3~5 Cells for VIN=12~28V
# 3~6 Cells for VIN=15~28V
R10
1K
Q1
2N3904
8
7
D5
1N4148
6
5
AIC1761/66
Fig. 9 Battery Charge Circuit for NiMH/NiCd Battery with Wide Range Input Voltage
A1012
Q1
+VIN
L1
R1
1N5819
D1
400µH
1N5819
D2
470
VBAT
C8
0.1µF
R17
330
12
8
11
R8
4
7
5
6
16
LED2
GREEN
R11
494
14
13
15
3
VREF
2K
2
390K
MODE
R9
10K
1.5K
1
VDD
TIMER
R18
AIC1766
LED1
RED
VNTC
LED
BATTERY
10
R14
R13
1.5K
THERMISTOR
9
ZD1
16V
R19
R4
560
R6
+
C2
1nF
R3
6.8nF
R5
5.1K
33K
27K
R7
1.1K
Q2
9014
R10
20K
R12
1.7K
VOUT
C5
0.1uF
C3
C1
220µF
25V
+
C4
100µF
25V
VBT
GND
C6
0.1µF
R16
150K
C7
4.7µF
6.3V
+
R15
150K
VB-
R2
GND
0.2
Note:
VIN should be higher than 10V, ZD1 is required when VIN exceed 18V.
Fast charge current is approximately 1A. Adjustable through R7.
Trickle charge current is adjustable through R12
Fig. 10 Step-Down Rechargeable Battery Charger
ANALOG INTEGRATIONS CORPORATION
www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
12
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
APPLICATION EXAMPLES (CONTINUED)
ZD1
GND
FB
D3
AIC1630
33K
R9
100K
C3
VDD
TIMER
VOUT
MODE
LED
1N4148
100K
R6
Charging current =0.8A
(RIF sets the Charging Current)
FIG. 11
+
1.5K
R13
1.5K
R12
AIC1761/1766
10nF
Note:
VREF
GND
22K C6
R7
0.82
RIF
0.1µF
C5
VBT
R11
120K
12K
R2
R5
C1
100µF
C4
Trickle
LBO
+
4.7µF
LBI
EXT
R3
+
C2
1N4148
VOUT
VIN
+
100µF
4.7V
Q1
IRFD020
SD
33K
VBAT
R4
220µF
R1
240K
D2
150
+VIN
(VIN < VBAT)
220
R10
Charging
Battery Pack
IN5819
L1
50µH
2A FUSE
D1
VIN must be lower than VBAT.
Short Circuit Condition is protected with a 2A Fuse.
Step-Up Rechargeable Battery Charger
+
2N3904
R2
750
AIC1630
FIG. 12
GND
TIP32C
Q3
220
9014
Q1
4.7K
R6
0.1µF
9014
Q4
2
R7
10
R9
R10
VBAT
0.1µF
C5
+
C6
100µF
390K
150K
+
VBT
R11
150K
R1 20K 9014
Q2
LED
Q6
9014
9V
ZD1
1N4001
680
R5 C1
MODE
AIC1761/1766
120
R15
VBAT
C2 BATTERY
4.7µF 2~8 cells
R3
10K
R2
VOUT
RIF sets Fast Charge Current, RIT sets Trickle Charge Current
Typical Efficiency = 75%.
With Short Circuit Protection.
R4
D1
+VIN
9~18V
VDD
TIMER
Step-Up/Down Rechargeable Battery Charger
R10
330
VREF
VBT
+
C3
4.7µF
120K
R15
Note: Fast Charge Current = 0.8A @VIN<VBAT
=(VIN - VBAT - 0.5)/0.82 @VIN>VBAT
Trickle charge Current = 30mA.
1.5K
R14
1.5K
R13
120K
R11
22K
R9
RIF
0.82
0.1µF
C5
Trickle
FB
2N2222
Q4
2N3904
Q5
+
Charging
GND
12K R5
Q2
100µF
C4
C3
GND
TIMER
R8
MODE
VREF
1.5K
R12
VDD
VOUT
LED
1.5K
R14
10K
R13
9014
Q5
Charging
LBO
C2
RIT
75K
R6
330
100K
LBI
EXT
+
220µF
VOUT
VIN
240K
R4
VIN
(+VIN can be either higher or lower
than the battery voltage.)
220
R12
Trickle
+
C1
100µF
SD
47K
R3
Battery Pack
0.1µF
ZD1
150
R1
TIP42C
Q3
4.7V
L1
IRFD020
Q1
50µH
IN5819 D2
AIC1761/1766
Note:
VIN=9V~18V for 2~8 cells
Fast Charge Current=400mA (
FIG. 13
V BE
0.65
≅
)
R7 / /R8 R7 / /R8
Step-Down Low-Side Current Sense Pulse Battery Charger
ANALOG INTEGRATIONS CORPORATION
www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
13
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
APPLICATION EXAMPLES (CONTINUED)
IN4001
VBAT of
Battery
150
9012
Q1
R3
To VBT pin of
AIC1761/1766
9014
Q2
12K
R1
R5
33
2W
Final Voltage of Battery
R26
6V
6.8K
5V
5.1K
4V
3.9K
3V
2.7K
R26
3.9K
9014
Q3
1K
R2
S1
Note:
The final voltage of battery is determined by R26.
Discharge current is decided by R5.
S1: Push to initiate discharge
Fig. 14 Discharge Circuit of Rechargeable Battery
+VIN
2.4K
R4
0.1µF
330K
R2
4.7M
R1
9014
Q1
C33
4.7M
R33
100K
R5
VDD
TIMER
MODE
AIC1761/1766
9014
Q2
VOUT
VREF
LED
VBT
GND
GND
Note:
Fig. 15
Frequency (about 1Hz) is determined by R33 and C33.
LED will flash when LED pin goes low.
Flashing-LED Circuit for Trickle Mode
+VIN
1M
R1
1nF
100K
R2
Q1
9014
C33
240K
R33
100K
R4
10K
R5
To
Buzzer
Q2
9014
VDD
TIMER
MODE
AIC1761/1766
VOUT
VREF
LED
VBT
GND
GND
Note:
Fig. 16
Frequency (about 1Hz) is determined by R33 and C33.
Buzzer will be activated when LED pin goes low.
Buzzer Circuit for Trickle Mode
ANALOG INTEGRATIONS CORPORATION
www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
14
AIC1761/1766
BATTERY CHARGE CONTROLLER
SPEC NO: DS-1761-02
PHYSICAL DIMENSION
8 LEAD PLASTIC DIP
8 LEAD PLASTIC SO
4.80±0.20
9.3±0.3
6.0±0.2
3.8±0.2
6.2±0.2
8.0±0.5
1.27±0.10
0.6±0.3
3.2±0.3
8.5±1.0
0.5±0.1
2.54±0.10
0.45±0.10
14 LEAD PLASTIC DIP
0.2 ± 0.1
1.5±0.2
2.5±0.1
10°max
0.015X45°
0.25±0.10
3.3±0.1
8° max.
14 LEAD PLASTIC SO
8.6±0.2
6.2±0.2
8.0±0.5
3.3±0.1
3.2±0.1
0.38 ×45°
1.27±0.10
0.6±0.3
1.5±0.2
0.25±0.1
10° max.
8.5±1.0
0.45±0.05
2.54±0.10
0.2±0.1
1.5±0.5
0.5±0.1
6.0±0.2
3.8±0.2
19.0±0.5
0.25±0.10
8° max.
UNIT: mm
ANALOG INTEGRATIONS CORPORATION
www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
15