U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
1 (17)
Fast Charge Controller for Drained NiCd/NiMH Batteries
Description
The fast-charge battery controller circuit, U2405B, uses
bipolar technology. The IC enables the designer to create
an efficient and economic charge system. The U2405B
incorporates intelligent multiple-gradient battery-
voltage monitoring and mains phase control for power
management. With automatic top-off charging, the
integrated circuit ensures that the charge device stops
regular charging before the critical stage of overcharging
is achieved. It incorporates an additional algorithm for
reactivating fully drained batteries especially after long-
time storage. It has two LED driver indications for charge
and temperature status.
Features
D Preformation algorithm for drained batteries
D Multiple gradient monitoring
D Temperature window (T
min
/T
max
)
D Exact battery voltage measurement without charge
D Phase control for charge-current regulation
D Top-off and trickle charge function
D Two LED outputs for charge status indication
D Disabling of d
2
V/dt
2
switch-off criteria
during battery formation
D Battery-voltage check
Applications
D Portable power tools
D Laptop/notebook personal computer
D Cellular/cordless phones
D Emergency lighting systems
D Hobby equipment
D Camcorder
Package: DIP18, SO20
Gradient
d
2
V/dt
2
and dV
5 (5)
Sync
R
Phase control
18 (20)
17 (19)
16 (18)
Power supply
V
S
= 8 to 26 V
Trigger output
V
i
Power - on control
V
Ref
6.5 V/10 mA
14 (15)
Oscillator
160 mV
Ref
Temp. control
T
max
Sensor
Battery
detection
V
Ref
= 5 V
Status control
Scan path
V
Batt
Monitor
0.1 to 4 V
Charge break
output
Control unit
13 (14)
12 (13)
11 (12)
3 (3)
10 (11)
6 (6)
7 (8)
8 (9)
9 (10)
4 (4)
1 (1)
15 (17)
2 (2)
94 8585
C
( ) SO 20, Pins 7 and 16 NC
Figure 1. Block diagram
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
2 (17)
Pin Description
Package: DIP18
18
10
1
2
3
4
5
6
7
8
9
11
12
13
14
15
16
17
Output
GND
LED2
LED1
93 7723 e
V
i
t
p
V
sync
C
R
V
Ref
Osc
S
TM.
V
S
V
Batt
OP
O
OP
I
T
max
Sensor
Package: SO20
18
10
1
2
3
4
5
6
7
8
9
11
12
13
14
15
16
17
Output
GND
LED2
LED1
94 8594
20
19
V
i
OP
O
t
p
NC
V
Batt
S
TM.
Osc
V
Ref
R
C
V
sync
V
S
NC
OP
I
T
max
Sensor
Pin
Symbol
Function
1
Output
Trigger output
2
GND
Ground
3
LED2
Display output "Green"
4
V
i
Phase angle control input voltage
5
OP
O
Operational amplifier output
6
OP
I
Operational amplifier input
7
T
max
Maximum temperature
8
Sensor
Temperature sensor
9
t
p
Charge break output
10
V
Batt
Battery voltage
11
LED1
LED display output "Red"
12
S
TM.
Test mode switch (status control)
13
Osc
Oscillator
14
V
Ref
Reference output voltage
15
V
S
Supply voltage
16
R
Ramp current adjustment
resistance
17
C
Ramp voltage capacitance
18
V
sync.
Mains synchronization input
Pin
Symbol
Function
1
Output
Trigger output
2
GND
Ground
3
LED2
Display output "Green"
4
V
i
Phase angle control input voltage
5
OP
O
Operational amplifier output
6
OP
I
Operational amplifier input
7
NC
Not connected
8
T
max
Maximum temperature
9
Sensor
Temperature sensor
10
t
p
Charge break output
11
V
Batt
Battery voltage
12
LED1
LED display output "Red"
13
S
TM.
Test mode switch (status control)
14
Osc
Oscillator
15
V
Ref
Reference output voltage
16
NC
Not connected
17
V
S
Supply voltage
18
R
Ramp current adjustment
resistance
19
C
Ramp voltage capacitance
20
V
sync.
Mains synchronization input
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
3 (17)
Sync
R
C
Phase control
18
17 16
Power supply
V
S
= 8 to 26
V
T
rigger output
V
i
Power on
control
V
Ref
6.5 V/10
mA
14
Oscillator
160 mV
Ref
T
emp. control
T
max
Sensor
Battery
detection
V
Ref
= 5
V
Status
control
Scan path
V
Batt
Monitor
0.1 to 4
V
Char
ge break
output
Contr
ol unit
Gradient
d
2
V/dt
2 & dV
13 12
11
3
10
5
6
7
8
9
4
94 8674
R
3
2.2 k
R
13
100 k
R
4
560 k
C
3
10 nF
C
2
0.22 F
R
0
270 k
C
0
10 nF
Red
D
7
D
8
Green
C
6
0.1 F
10 k
R
2
D
1
10
1
D
4
D
5
D
2
D
3
Th1
Th2
Mains
D
6
R
10
R
11
560
2x
R
9
R
8
1 k
R
7
1 k
BC 308
T
1
R
1
1 k
R
5
C
1
470 F
R
B1
10 k
C
R
1 F
R
6
10 k
C
4
R
T3
24 k
0.1 F
C
8
R
T2
100 k
R
T1
To
V
Ref
(Pin 14)
R
B2
C
7
4.7 F
R
B3
NTC
DC
0.2
Battery
(4 cells)
T
o
Pin 4
From
R
T1
/ R
T2
15
2
1 k
16 k
R
sh
160 mV
12 k
I ch
W
W
W
W
m
W
m
1 F
m
W
W
W
m
W
W
m
W
10 k
m
W
W
W
W
m
W
W
W
W
V
S
V
S
From Pin 15
Figure 2. Block diagram with external circuit (DIP pinning)
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
4 (17)
General Description
The integrated circuit, U2405B, is designed for charging
Nickel-Cadmium (NiCd) and Nickel-Metal-Hydride
(NiMH) batteries. Fast charging results in voltage lobes
when fully charged (figure 3). It supplies two
identifications ( i. e., + d
2
V/dt
2
,
and
DV) to end the
charge operation at the proper time.
As compared to the existing charge concepts where the
charge is terminated
* after voltage lobes * according
to
DV and temperature gradient identification, the
U2405B takes into consideration the additional changes
in positive charge curves, according to the second
derivative of the voltage with respect to time (d
2
V/dt
2
).
The charge identification is the sure method of switching
off the fast charge before overcharging the battery. This
helps to give the battery a long life by hindering any
marked increase in cell pressure and temperature.
Even in critical charge applications, such as a reduced
charge current or with NiMH batteries where weaker
charge characteristics are present multiple gradient
control results in very efficient switch-off.
An additional temperature control input increases not
only the performances of the charge switching
characteristics but also prevents the general charging of
a battery whose temperature is outside the specified
window.
A specific preformation algorithm is implemented for
reactivating fully drained batteries especially in the case
of batteries that have been stored for a long time.
A constant charge current is necessary for continued
charge-voltage characteristic. This constant current
regulation is achieved with the help of internal amplifier
phase control and a simple shunt-current control tech-
nique.
All functions relating to battery management can be
achieved with DC-supply charge systems. A DC-DC-
converter or linear regulator should take over the function
of power supply. For further information please refer to
the applications.
5 V
95 10616
Battery insertion
Fast charge stop
Top-off charge stop
Top-off
charge rate
1/4 I
O
Battery
voltage
without
charge control
preformation
t
1
= 5 min
Trickle
1/256 I
O
t
Fast charge rate I
O
t
2
= 20 min
) d
2
V
dt
2
,
D
V
) d
2
V
dt
2
DV
charge rate
1.6 V
DV
I (R
B1)
Figure 3. Charge function diagram, f
osc
= 800 Hz
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
5 (17)
Flow Chart Explanation, f
osc
= 800 Hz
(Figures 2, 3 and 4)
Battery pack insertion disables the voltage lock at battery
detection input Pin 10. All functions in the integrated
circuit are reset. For further description, DIP-pinning is
taken into consideration.
Battery Insertion and
DV
Monitoring
After battery insertion fast charge I
o
begins when the
input voltage V
Batt
is higher than 1.6 V. For the first
5 minutes the d
2
V/dt
2
-gradient recognition is suppressed,
DV monitoring is activated. In case the detected V
Batt
voltage is less then 1.6 V, the special preformation
procedure will be activated. The reference level with
respect to the cell voltage can be adjusted by the resistor
R
B3
(see figure 2).
Preformation Procedure
Before fast charge of fully drained or long time stored
batteries begin, a reactivation is necessary. The
preformation current is dependent on pull-up resistor
R
B1
. The fast charge starts only after the V
Batt
is higher
than 1.6 V level. During the first 10 minutes the green
LED2 is blinking. If, after 10 minutes, V
Batt
voltage has
not reached the reference level, the indication changes to
red blinking LED1. The charge will continue with
preformation rate I (R
B1
). In case V
Batt
increases to 1.6 V
reference level, the fast charge rate current, I
o
, is
switched-on and the green LED2 is blinking.
DV Cut-Off (Monitoring)
When the signal at Pin 10 of the DA converter is 12 mV
below the actual value, the comparator identifies it as a
voltage drop of
DV. The validity of DV cut-off is
considered only if the actual value is below 12 mV for
three consecutive cycles of measurement.
d
2
V/dt
2
-Gradient
If there is no charge stop within the first 5 minutes after
battery insertion, then d
2
V/dt
2
monitoring will be active.
In this actual charge stage, all stop-charge criteria are
active.
When close to the battery's capacity limit, the battery
voltage curve will typically rise. As long as the +d
2
V/dt
2
stop-charging criteria are met, the device will stop the fast
charge activities.
Top-Off Charge Stage
By charge disconnection through the + d
2
V/dt
2
mode, the
device switches automatically to a defined protective
top-off charge with a pulse rate of 1/4 I
O
(pulse time,
t
p
= 5.12 s, period, T = 20.48 s).
The top-off charge time is specified for a time of
20 minutes @ 800 Hz.
Trickle Charge Stage
When top-off charge is terminated, the device switches
automatically to trickle charge with 1/256 I
O
(t
p
= 5.12 s,
period = 1310.72 s). The trickle continues until the
battery pack is removed.
Basic Description
Power Supply, Figure 2
The charge controller allows the direct power supply of
8 to 26 V at Pin 15. Internal regulation limits higher input
voltages. Series resistance, R
1
, regulates the supply
current, I
S
, to a maximum value of 25 mA. Series
resistance is recommended to suppress the noise signal,
even below 26 V limitation. It is calculated as follows.
R
1min
w
V
max
26 V
25 mA
R
1max
v
V
min
8 V
I
tot
where
I
tot
= I
S
+ I
RB1
+ I
1
V
max,
V
min
= Rectified voltage
I
S
= Current consumption (IC) without load
I
RB1
= Current through resistance, R
B1
I
1
= Trigger current at Pin 1
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
6 (17)
t
ch
>10 min
Batt. inserted
*)
Reset
LED1,2 off
Power on reset
Temp. range ?
LED1 on
LED2 blinking
V
Batt
> 1.6 V
Fast charge
begins
LED2 blinking
V
Batt
4 V
dV
switch off
Batt. inserted
*)
LED1 blinking
Temp. range ?
no
Charge stop
LED1 off
LED2 blinking
LED1 blinking
LED2 off
no
Charge time
t
1
>5 min?
dV and d
2
V/dt
2
monitoring activated
Batt temp
range?
LED1 on
dV
disconnect
LED2 on
Trickle charge
1/256 I
O
Batt. inserted
*)
Batt. inserted
*)
LED2 on
Top off charge
1/4 I
O
d
2
V/dt
2
disconnect ?
t
2
> 20 min
Start
95 10625
Preformation
current I
RB1
no
yes
no
no
yes
no
yes
yes
no
no
no
no
no
yes
yes
*) 70 mV > V
Batt
<
5 V
yes
no
yes
yes
yes
yes
yes
no
no
Figure 4. Flow chart
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
7 (17)
Battery Voltage Measurement
The battery voltage measurement at Pin 10 (ADC-
converter) has a range of 0 V to 4 V, which means a
battery pack containing two cells can be connected
without a voltage divider.
If the AD converter is overloaded (V
Batt
w 4 V) a safety
switch off occurs. The fast charge cycle is terminated by
automatically changing to the trickle charge.
Precaution should be taken that under specified charge
current conditions, the final voltage at the input of the
converter, Pin 10, should not exceed the threshold voltage
level of the reset comparator, which is 5 V. When the
battery is removed, the input (Pin 10) is terminated across
the pulled-up resistance, R
B1,
to the value of 5 V-reset-
threshold. In this way, the start of a new charge sequence
is guaranteed when a battery is reinserted.
If the battery voltage exceeds the converter range of 4 V,
adjusting it by the external voltage divider resistance, R
B2
and R
B3
is recommended.
Value of the resistance, R
B3
is calculated by assuming
R
B1
= 1 k
W, R
B2
= 10 k
W, as follows:
R
B3
+ R
B2
V
10max
V
Bmax
V
10max
The minimum supply voltage, V
smin
, is calculated for
reset function after removing the inserted battery
according to:
V
smin
+
0.03mA
@ R
B3
R
B1
) R
B2
) 5V R
B1
) R
B2
) R
B3
R
B3
where:
V
10max
= Max voltage at Pin 10
V
Smin
= Min supply voltage at the IC (Pin 15)
V
Bmax
= Max battery voltage
The voltage conditions mentioned above are measured
during charge current break (switch-off condition).
7 V
DAC control
comparator
comparator
10
- dV Recognition
V
DAC
V
DAC
R
B1
R
B2
R
B3
V
6
Battery
R
sh
V
S
95 10174
+
+
15
V
Ref
=
12 mV
V
Ref
=
4.3 V
V
Ref
= 0.1 V
Reset
I
ch
+
=
V
Batt
Reset
V
B
Figure 5. Input configuration for the battery voltage measurement
Table 1. valid when V
10max
= 3.5 V
Cell No.
1
2
3
4
5
6
7
8
9
10
11
12
V
Smin
(V)
8
8
8
9
11
13
15
17
19
21
23
25
R
B3
(k
W)
51
16
10
7.5
5.6
4.7
3.9
3.3
3
2.7
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
8 (17)
Analog-Digital-Converter (ADC),
Test Sequence
A special analog-digital-converter consists of a five-bit
coarse and a five-bit fine converter . It operates by a linear
count method which can digitalize a battery voltage of
4 V at Pin 10 in 6.5 mV steps of sensitivity.
In a duty cycle, T, of 20.48 s, the converter executes the
measurement from a standard oscillation frequency of
f
osc
= 800 Hz. The voltage measurement is during the
charge break time of 2.56 s (see figure 6), i.e., no-load
voltage (or currentless phase). Therefore it has optimum
measurement accuracy because all interferences are
cut-off during this period (e.g., terminal resistances or
dynamic load current fluctuations).
After a delay of 1.28 s the actual measurement phase of
1.28 s follows. During this idle interval of cut-off
conditions, battery voltage is stabilized and hence
measurement is possible.
An output pulse of 10 ms appears at Pin 9 during charge
break after a delay of 40 ms. The output signal can be used
in a variety of way, e.g., synchronising the test control
(reference measurement).
Plausibility for Charge Break
There are two criterian considered for charge break
plausibility:
DV Cut-Off
When the signal at Pin 10 of the DA converter is 12 mV
below the actual value, the comparator identifies it as a
voltage drop of
DV. The validity of DV cutt-off is
considered only if the actual value is below 12 mV for
three consective cycles of measurement.
d
2
V/dt
2
Cut-Off
A four bit forward/ backward counter is used to register
the slope change (d
2
V/dt
2
, V
Batt
slope). This counter is
clocked by each tracking phase of the fine AD-counter.
Beginning from its initial value, the counter counts the
first eight cycles in forward direction and the next eight
cycles in reverse direction. At the end of 16 cycles, the
actual value is compared with the initial value. If there is
a difference of more than two LSB-bit (13.5 mV) from the
actual counter value, then there is an identification of
slope change which leads to normal charge cut-off. A
second counter in the same configuration is operating in
parallel with eight clock cycles delay, to reduce the total
cut-off delay, from 16 test cycles to eight test cycles.
2.56 s
T= 20.48 s
t
10 ms
40 ms
t
t
1.28 s
1.28 s
charge
break
output
Status
ADC
conversion
time
(internal)
94 8693
Charge
Charge break
Figure 6. Operating sequence of voltage measurements
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
9 (17)
Temperature Control, Figure 7
When the battery temperature is not inside the specified
temperature windows, the overal temperature control will
not allow the charge process. Sensor short circuit or
interruption also leads to switch-off.
Differentiation is made whether the battery exceeds the
maximum allowable temperature, T
max
, during the
charge phase or the battery temperature is outside the
temperature window range before battery connection.
A permanent switch-off follows after a measurement
period of 20.48 s, if the temperature exceeds a specified
level, which is denoted by a status of a red LED
1
. A charge
sequence will start only when the specified window
temperature range is attained. In such a case, the green
LED
2
starts blinking immediately showing a quasi charge
readiness, even though there is no charge current flow.
NTC sensors are normally used to control the temperature
of the battery pack. If the resistance values of NTC are
known for maximum and minimum conditions of
allowable temperature, then other resistance values, R
T1
,
R
T2
and R
T3
are calculated as follows:
suppose R
T2
= 100 k
W, then
R
T1
+ R
NTCmax
V
Ref
4V
4V
R
T3
+ R
NTCmin
R
T2
R
T1
7 V
7
R
T2
R
T3
14
+
7 V
R
T1
NTC
sensor
8
94 8682
V
Ref
V
Ref
= 4 V
High
temperature
Low
temperature
+
Sensor
V
Ref
T
max
Figure 7. Temperature window
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
10 (17)
Current Regulation Via Phase
Control (Figure 8)
Phase Control
An internal phase control monitors the angle of current
flow through the external thyristors as shown in figure 2.
The phase control block represents a ramp generator
synchronized by mains zero cross over and a comparator.
The comparator will isolate the trigger output, Pin 1, until
the end of the half wave (figure 8) when the ramp voltage,
V
ramp,
reaches the control voltage level, V
i,
within a
mains half wave.
Charge Current Regulation (Figure 2)
According to figure 2 the operational amplifier (OpAmp)
regulates the charge current, I
ch
(= 160 mV / R
sh
),
average value. The OpAmp detects the voltage drop
across the shunt resistor (R
sh
) at input Pin 6 as an actual
value. The actual value will then be compared with an
internal reference value (rated value of 160 mV).
The regulator's output signal, V
5,
is at the same time the
control signal of the phase control, V
i
(Pin 4). In the
adjusted state, the OpAmp regulates the current flow
angle through the phase control until the average value at
the shunt resistor reaches the rated value of 160 mV.
The corresponding evaluation of capacitor C
R
at the
operational amplifier (regulator) output determines the
dynamic performance of current regulation.
Internal
zero pulse
Current flow angle
6V
0ms
10ms
20ms
30ms
100mV
93 7697 e
f
mains
= 50 Hz
V
sync
(Pin 18)
Ramp
voltage
(Pin 17
)
V
i
V
i
V
i
Trigger
output
(Pin 1)
Figure 8. Phase control function diagram
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
11 (17)
Status Control
Status control inside and outside the charging process are designated by LED
1
and LED
2
outputs given in the table
below:
LED1 (red)
LED2 (green)
Status
OFF
ON
Top-off charge, trickle charge
OFF
Blinking
Quick charge
ON
OFF
Temperature out of the window
Blinking
OFF
Drained battery (0.1 V < V
Batt
> 1.6 V, if t > 10 min.)
Battery break, short circuit
ON
Blinking
Temperature out of window before battery insertion or power on
OFF
OFF
No battery (V
Batt
> 5 V)
The blink frequency of LED outputs can be calculated as
follows:
f
(LED)
+
Oscillator frequency, f
osc
1024
Oscillator
Time sequences regarding measured values and
evaluation are determined by the system oscillator. All
the technical data given in the description are with the
standard frequency 800 Hz.
It is possibe to alter the frequency range in a certain
limitation. Figure 9 shows the frequency versus
resistance curves with different capacitance values.
Oscillation Frequency Adjustment
Recommendations:
0.5C charge
0.5
500 Hz =
250 Hz
1C charge
500 Hz
2C charge
2
500 Hz = 1000 Hz
3C charge
3
500 Hz = 1500 Hz
0.1
1
10
100
1000
10000
R ( k )
O
f
O
( kHz )
10
95 11408
W
C
O
=2.2nF
C
O
=4.7nF
C
O
=10nF
Figure 9. Frequency versus resistance for different capacitance values
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
12 (17)
Absolute Maximum Ratings
Reference point Pin 2 (GND), unless otherwise specified
Parameters
Symbol
Value
Unit
Supply voltage
Pin 15
V
S
26
V
pp y
g
Voltage limitation
I
S
= 10 mA
31
Current limitation
Pin 15
t < 100
ms
I
S
25
100
mA
Voltages at different pins Pins 1, 3 and 11
Pins 4 to 10, 12 to 14 and 16 to 18
V
26
7
V
Currents at different pins Pin 1
Pins 3 to 14 and 16 to 18
I
25
10
mA
Power dissipation
T
amb
= 60
C
P
tot
650
mW
Ambient temperature range
T
amb
10 to +85
C
Junction temperature
T
j
125
C
Storage temperature range
T
stg
40 to +125
C
Thermal Resistance
Parameters
Symbol
Value
Unit
Junction ambient
DIP18
SO20
R
thJA
R
thJA
80
100
K/W
K/W
Electrical Characteristics
V
S
= 12 V, T
amb
= 25
C, reference point Pin 2 (GND), unless otherwise specified
Parameters
Test Conditions / Pins
Symbol
Min.
Typ.
Max.
Unit
Power supply
Pin 15
Voltage range
V
S
8
26
V
Power-on threshold
ON
OFF
V
S
3.0
4.7
3.8
5.7
V
V
Current consumption
without load
I
S
3.9
9.1
mA
Reference
Pin 14
Reference voltage
I
Ref
= 5 mA
I
Ref
= 10 mA
V
Ref
6.19
6.14
6.5
6.5
6.71
6.77
V
V
Reference current
I
Ref
10
mA
Temperature coefficient
TC
0.7
mV/K
Operational amplifier OP
Output voltage range
I
5
= 0
Pin 5
V
5
0.15
5.8
V
Output current range
V
5
= 3.25 V
Pin 5
I
5
80
mA
Output pause current
Pin 5
I
pause
100
mA
Non-inverting input voltage
Pin 6
V
6
0
5
V
Non-inverting input current
Pin 6
I
6
0.5
mA
Comparator or temperature control
Input current
Pins 7 and 8
I
7, 8
0.5
mA
Input voltage range
Pins 7 and 8
V
7, 8
0
5
V
Threshold voltage
Pin 8
V
8
3.85
4.15
V
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
13 (17)
Unit
Max.
Typ.
Min.
Symbol
Test Conditions / Pins
Parameters
Charge break output
Pin 9
Output voltage
High, I
9
= 4 mA
Low, I
9
= 0 mA
V
9
8.4
100
V
mV
Output current
V
9
= 1 V
I
9
10
mA
Battery detection
Pin 10
Analog-digital converter
Conversion range
Full scale level
V
Batt
0
3.85
4.0
V
Input current
0.1 V
v V
Batt
v 4.5 V
I
Batt
0.5
mA
Input voltage for reset
V
Batt
4.8
5.0
5.3
V
Input current for reset
V
Batt
y 5 V
I
Batt
8
35
mA
Battery detection
Maximum voltage
D V
Batt
80
120
mV
Hysteresis
Maximum voltage
V
hys
15
mV
Mode select
Pin 12
Treshold voltage
Testmode
V
12
4.7
V
Input current
I
12
20
mA
Input current
Normal mode Pin 12 open
12
0
m
Sync. oscillator
Pin 13
Frequency
R = 150 k
W
C = 10 nF
f
osc
800
Hz
Threshold voltage
High level
Low level
V
T(H)
V
T(L)
4.3
"3%
2.2
"3%
V
Input current
I
13
0.5
0.5
mA
Phase control
Ramp voltage
R
= 270 k
W
Pin 16
V
16
2.9
3.9
V
Ramp current
I
16
0
100
mA
Ramp voltage range
V
17
0
5
V
Ramp discharge current
I
17
3.3
8
mA
Synchronisation
Pin 18
Minimum current
V
sync
v 80 mV
I
sync
10
2
mA
Maximum current
V
sync
= 0 V
I
sync
15
30
mA
Zero voltage detection
V
sync
83
100
135
mV
Hysteresis
V
hys
15
mV
Charge stop criteria (function) Pin 10
Positive gradient-turn-off
threshold
f
osc
= 800 Hz
d
2
V/dt
2
4.8
mV/
min
2
DV-turn-off threshold
DV
12
mV
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
14 (17)
R
T1
10
W
R
1
R
B1
1 k
W
R
B2
10 k
W
R
B3
16 k
W
Output
1
V
sync
18
V
Batt
Sensor
10
8
NTC
LM358
Battery
C
8
0.1 F
S
TM
6
12 k
W
C
4
1 F
R
6
10 k
W
15
V
S
C
1
2
220 F
LED1
16
R
C
17
5
OP
O
4
14
V
i
V
Ref
11
TLHR5400
LED2
3
TLHG5400
Green
Ready
R
5
1 k
W
7
T
max
R
T2
100 k
W
R
T3
24 k
W
9
12
t
p
13
Osc
R
O
270 k
W
C
O
10 nF
94 8733
OP
I
GND
R
15
100 k
W
R
13
100 k
W
R
14
100 k
W
R
12
100 k
W
C
7
4.7 F
I
ch
= 0.16
V/R
sh
0.2
WW
/ 1
W
L
1
200 H
C
5
47 F
D
1
BYV27/50
C
10
10 F
8
V
to
R
sh
+
Red
T
emp
1 k
W
R
2
1 k
W
R
3
T1
C
R
1 F
R
4
22 k
W
C
3
1 nF
BD646
T2
BC237
T3
R
7
10 k
W
R
8
10 k
W
R
10
10 k
W
R
11
4.7 k
W
R
16
1 k
W
D
2
1N4148
C
2
0.22 F
R
9
10 k
W
T4
BC308
4
8
/ V
S
+
m
m
m
m
m
m
m
m
m
26 V
R
17
1k
1 A
x)
x) Manufacturer Pikatron
W
D
3
BYV27/50
Figure 10. Car battery supplied charge system with high side current detection for 4 NiCd/NiMH cells @ 800 mA
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
15 (17)
2.2 k
W
D
2
D
3
Th1
D
5
R
11
560
W
R
9
10 k
W
1 k
W
BC 308
Red
T
emp
BYT86
R
10
560
W
C
7
4.7
C
6
D
6
R
8
T
1
R
T1
4148
R
2
100 k
W
R
3
R
13
R
7
10 k
W
1 k
W
4148
D
1
10
W
0.1
R
1
R
B1
1 k
W
R
B2
10 k
W
R
B3
16 k
W
Output
1
V
sync
18
V
Batt
Sensor
10
8
NTC
R
22
10 k
W
C
10
0.1
R
23
10 k
W
BC 308
R
24
10 k
W
BC 307
BC 307
D
10
4148
D
11
4148
R
25
6.2 k
W
S1
R
29
10 k
W
R
21
1 k
W
R
20
10
W
/
4 W
0.1
W
BD 649
Battery
4148
Th2
D
4
4148
C
8
0.1
S
TM
6
12 k
W
C
4
1
R
6
10 k
W
15
V
S
C
1
2
220
LED2
16
R
R
4
560 k
W
17
10 nF
C
3
C
R
5
4.7
OP
O
4
14
V
i
V
Ref
11
TLHG5400
LED1
3
TLHR5400
Green
Ready
R
5
1 k
W
7
T
max
R
T2
100 k
W
R
T3
24 k
W
9
12
t
p
13
Osc
R
O
270 k
W
C
O
10 nF
94 8734
OP
I
GND
C
2
0.22
Mains
D
12
4148
V
Batt (Pin 10)
R
28
R
26
R
27
10 k
W
10 k
W
1 k
W
R
sh
= 0.16
V/I
ch
I
ch
C
m
F
m
F
m
F
m
F
m
F
m
F
m
F
m
F
BC 308
Sensor (Pin 8)
D
13
D
14
D ,
13
D = 1N4148
14
T
2
T
5
T
4
T
6
T
3
Figure 11. Standard application with predischarge for 8 NiCd/NiMH cells @ 1600 mA
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
16 (17)
Package Information
13019
Package DIP18
Dimensions in mm
0.5 min
technical drawings
according to DIN
specifications
7.77
7.47
23.3 max
4.8 max
3.3
6.4 max
0.36 max
9.8
8.2
1.64
1.44
0.58
0.48
2.54
20.32
18
10
1
9
13038
technical drawings
according to DIN
specifications
Package SO20
Dimensions in mm
9.15
8.65
11.43
12.95
12.70
2.35
0.25
0.10
0.4
1.27
7.5
7.3
0.25
10.50
10.20
20
11
1
10
U2405B
TELEFUNKEN Semiconductors
Rev. A2, 14-Nov-96
17 (17)
Ozone Depleting Substances Policy Statement
It is the policy of TEMIC TELEFUNKEN microelectronic GmbH to
1. Meet all present and future national and international statutory requirements.
2. Regularly and continuously improve the performance of our products, processes, distribution and operating systems
with respect to their impact on the health and safety of our employees and the public, as well as their impact on
the environment.
It is particular concern to control or eliminate releases of those substances into the atmosphere which are known as
ozone depleting substances ( ODSs ).
The Montreal Protocol ( 1987 ) and its London Amendments ( 1990 ) intend to severely restrict the use of ODSs and
forbid their use within the next ten years. Various national and international initiatives are pressing for an earlier ban
on these substances.
TEMIC TELEFUNKEN microelectronic GmbH semiconductor division has been able to use its policy of
continuous improvements to eliminate the use of ODSs listed in the following documents.
1. Annex A, B and list of transitional substances of the Montreal Protocol and the London Amendments respectively
2 . Class I and II ozone depleting substances in the Clean Air Act Amendments of 1990 by the Environmental
Protection Agency ( EPA ) in the USA
3. Council Decision 88/540/EEC and 91/690/EEC Annex A, B and C ( transitional substances ) respectively.
TEMIC can certify that our semiconductors are not manufactured with ozone depleting substances and do not contain
such substances.
We reserve the right to make changes to improve technical design and may do so without further notice.
Parameters can vary in different applications. All operating parameters must be validated for each customer
application by the customer. Should the buyer use TEMIC products for any unintended or unauthorized
application, the buyer shall indemnify TEMIC against all claims, costs, damages, and expenses, arising out of,
directly or indirectly, any claim of personal damage, injury or death associated with such unintended or
unauthorized use.
TEMIC TELEFUNKEN microelectronic GmbH, P.O.B. 3535, D-74025 Heilbronn, Germany
Telephone: 49 ( 0 ) 7131 67 2831, Fax number: 49 ( 0 ) 7131 67 2423
PDF 
ZIP