LM1042 Fluid Level Detector
February 1995
LM1042 Fluid Level Detector
General Description
The LM1042 uses the thermal-resistive probe technique to
measure the level of non-flammable fluids An output is pro-
vided proportional to fluid level and single shot or repeating
measurements may be made All supervisory requirements
to control the thermal-resistive probe including short and
open circuit probe detection are incorporated within the de-
vice A second linear input for alternative sensor signals
may also be selected
Features
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Selectable thermal-resistance or linear probe inputs
Control circuitry for thermal-resistive probe
Single-shot or repeating measurements
Switch on reset and delay to avoid transients
Output amplifier with 10 mA source and sink capability
Short or open probe detection
a
50V transient protection on supply and control input
7 5V to 18V supply range
Internally regulated supply
b
40 C to
a
80 C operation
Block Diagram
TL H 8709 鈥?1
C
1995 National Semiconductor Corporation
TL H 8709
RRD-B30M115 Printed in U S A