U4790B

www.DataSheet4U.com U4790B Automotive Lamp-Outage Monitor, VT = 8 mV, VZ(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 V4,6 = VS – VT where VT = 8 mV. If the voltage drop across shunt resistor, Rsh, 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 VS 2 Rsh Z2 – + & Z5 0.6 VS – + 8 – + 6 Z3 1 95 10606 VBatt 7 5 OUT1 4 Rsh 3 OUT2 & Lamps R1 150 W Figure 1. Schematic and application circuit TELEFUNKEN Semiconductors Rev. A2, 03-Dec-97 1 (5) DataSheet 4 U .com www.DataSheet4U.com U4790B Pin Description Input switch VRef IN2 OUT1 Pin 1 2 3 4 5 6 7 8 Symbol GND VS OUT2 IN1 OUT1 IN2 VRef Input Function Reference point, ground Supply voltage Output 2 Input 1 Output 1 Input 2 Reference voltage Input switch GND VS OUT2 IN1 1 2...