U6046B Datasheet, PDF (3/13 Pages) TEMIC Semiconductors – Rear Window Heating Timer

U6046B
Functional Description
Power Supply (Pin 8)
For reasons of interference protection and surge immunity, the supply voltage (pin 8)
must be provided with an RC circuit as shown in Figure 3. Dropper resistor, R₁, limits the
current in case of overvoltage, whereas C₁ smoothes the supply voltage at pin 8.
Recommended values are: R₁ = 510 W, C1 = 47 µF.
The integrated Z-diode (14 V) protects the supply voltage, V_S. Therefore, the operation
of the IC is possible between 6 V and 16 V, supplied by V_Batt.
However, it is possible to operate the integrated circuit with a 5 V supply, but it should be
free of interference voltages. In this case, pin 7 is connected to pin 8 as shown in Figure
4, and the R₁C₁ circuit is omitted.
Figure 3. Basic Circuit for 12 V Supply and Oscillator
V_Batt
R₁ 510 W
C₂
C₁
R₂
47 mF/
16 V ₈
7
6
5
U6046B
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2
3
4
Figure 4. Basic Circuit for V_S = 5 V
V_S = 5 V
C₂
R₂
V_Batt
8
7
6
5
U6046B
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2
3
4
3
4674A–AUTO–01/03