U4791B Datasheet, PDF (1/5 Pages) TEMIC Semiconductors – Automotive Lamp Outage Monitor, VT = 53 mV

U4791B
Automotive Lamp Outage Monitor, V_T = 53 mV
Description
The monolithic integrated bipolar circuit, U4791B, is de-
signed 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 whereas
V_T = 53 mV.
The integrated circuit is recommended for the application
of parallel connected lamps. If the voltage drop across
shunt resistor, R_sh, exceeds 53 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.
A not used comparator 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
U4791B
U4791B–FP
Block Diagram
Package
DIP8
SO8
V_S
2
R_sh
Z₂
4
7
–
&
+
R_sh
8
0.6 V_S
–
+
–
+
&
6
Lamps
1
R_{1 150 W}
Remarks
V_Batt
5 _OUT1
Z₅
3 _OUT2
Z₃
95 10613
Figure 1. Schematic and application circuit
TELEFUNKEN Semiconductors
1 (5)
Rev. A2, 17-Dec-96