U243B
Electrical Characteristics
Typical values under normal operation in application circuit figure 1, V
S
(+49, Pins 2 and 6) = 12 V
Reference point ground (–31), T
amb
= 25°C, unless otherwise specified
Parameters
Test Conditions / Pin
Supply voltage range
Pins 2 and 6
Supply current,
Pins 2 and 6
dark phase or stand-by
Supply current,
Pins 2 and 6
bright phase
Z–diode limitation
I
S2, 6
= 70 mA
Pins 2 and 6
Relay output,
saturation voltage
I
0
= 150 mA, V
S
= 9 V
Pin 3
Relay output,
Pin 3
reverse current
Relay coil resistance
Start delay
(first bright phase)
Frequency-determining
resistor
Frequency-determining
capacitor
Frequency tolerance (normal flashing, basic frequency
f
1
not including the tolerance of the external compo-
nents R
1
and C
t
)
Bright period
(basic frequency f
1
)
Bright period
(control frequency f
2
)
Frequency increase
(lamp failure)
Control-signal threshold
V
S
= 15 V
Pin 7
V
S
= 9 V
Pin 7
V
S
= 12 V
Pin 7
Transfer resistance
49a to common for
stand-by
Lamp load
Symbol
V
S
(+49)
I
S
I
S
V
S
Min
Typ
9 ... 15
4.5
7.0
23
Max
Unit
V
mA
mA
V
8
11
V
O
I
O
R
L
t
on
R
t
C
t
∆f
1
∆f
1
∆f
2
f
2
V
R3
V
R3
V
R3
R
P
P
L
10
6.8
1.0
0.1
60
10
510
47
V
mA
W
ms
k
W
m
F
%
%
%
–5
47
37
2.15 f
1
85
66
76
91
71
81
2
+5
53
45
2.3f
1
97
76
87
5
mV
mV
mV
k
W
W
Applications
D
Flashing generator, operation with smaller loads
(≥ 2 W)
By adding a resistor to the application circuit (figure 1),
defined operation with lamp loads
≥
2 W is possible. The
voltage drop across the resistor R
4
is generated by the
current flowing over the relay and should be about 15 mV.
With a relay current of 150 mA (relay resistance 73 Q),
this requires a resistance of R
4
= 100 m
W
. The change of
TELEFUNKEN Semiconductors
Rev. A1, 05-Sep-96
the operating point by 15 mV results in a corresponding
change of the control signal threshold by 15 mV. For a
lamp current of 2.7 A, a measuring resistance of
R
3
=
81 mV – 15 mV
2.7 A
= 25 m
W
results.
3 (6)
Preliminary Information
TEMIC [ TEMIC SEMICONDUCTORS ]
