U4790B Datasheet, PDF (1/5 Pages) List of Unclassifed Manufacturers – Automotive Lamp-Outage Monitor, VT = 8 mV, VZ(3,5) = 22 V

U4790B
Automotive Lamp-Outage Monitor, V_T = 8 mV, V_Z(3,5) = 22 V
Description
The bipolar IC U4790B is designed as a monitor for lamp
failure in automobiles. The comparator threshold is
matched to the PTC characteristic of incandescent lamps.
The threshold is tied to a typical value of V_4,6 = V_S – V_T
where V_T = 8 mV.
If the voltage drop across shunt resistor, R_sh, exceeds
8 mV, the output is turned off, otherwise the output is
turned on. Without supply voltage or open input Pin 8, the
output is turned off. An unused comparator input must be
connected to Pin 7.
Features
D 10 kV–ESD protection
D Two comparators with common reference
D Tight threshold tolerance
D Threshold matched to PTC characteristic
of incandescent lamps
D Temperature compensated
D NPN output
D Interference and damage–protection
according to VDE 0839
D EMI protection
D Reversal polarity protection
D Load-dump protection
Ordering Information
Extended Type Number
U4790B
Package
DIP8
Remarks
Block Diagram
V_S
2
7
R_sh
Z₂
4
–
&
+
R_sh
8
0.6 V_S
–
+
–
+
&
6
Lamps
1
R₁ 150 W
Figure 1. Schematic and application circuit
V_Batt
5 _OUT1
Z₅
3 _OUT2
Z₃
95 10606
TELEFUNKEN Semiconductors
1 (5)
Rev. A2, 03-Dec-97