Electrical Characteristics
(Continued)
Note 1:
“Absolute Maximum Ratings” indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
functional, but do not guarantee specific performance limits.
Note 2:
For operating at temperatures above 25˚C, the LM392 and the LM2924 must be derated based on a 125˚C maximum junction temperature and a thermal
resistance of 122˚C/W which applies for the device soldered in a printed circuit board, operating in still air ambient. The dissipation is the total of both amplifiers — use
external resistors, where possible, to allow the amplifier to saturate or to reduce the power which is dissipated in the integrated circuit.
Note 3:
Short circuits from the output to V
+
can cause excessive heating and eventual destruction. When considering short circuits to ground, the maximum output
current is approximately 40 mA for the op amp and 30 mA for the comparator independent of the magnitude of V
+
. At values of supply voltage in excess of 15V, con-
tinuous short circuits can exceed the power dissipation ratings and cause eventual destruction.
Note 4:
This input current will only exist when the voltage at any of the input leads is driven negative. It is due to the collector-base junction of the input PNP tran-
sistors becoming forward biased and thereby acting as input diode clamps. In addition to this diode action, there is also lateral NPN parasitic transistor action on the
IC chip. This transistor action can cause the output voltages of the amplifiers to go to the V
+
voltage level (or to ground for a large overdrive) for the time duration
that an input is driven negative. This is not destructive and normal output states will re-establish when the input voltage, which was negative, again returns to a value
greater than −0.3V (at 25˚C).
Note 5:
These specifications apply for V
+
= 5V, unless otherwise stated. For the LM392, temperature specifications are limited to 0˚C
≤
T
A
≤
+70˚C and the LM2924
temperature specifications are limited to −40˚C
≤
T
A
≤
+85˚C.
Note 6:
At output switch point, V
O
≅
1.4V, R
S
= 0Ω with V
+
from 5V to 30V; and over the full input common-mode range (0V to V
+
− 1.5V).
Note 7:
The direction of the input current is out of the IC due to the PNP input stage. This current is essentially constant, independent of the state of the output so
no loading change exists on the input lines.
Note 8:
The input common-mode voltage or either input signal voltage should not be allowed to go negative by more than 0.3V. The upper end of the common-mode
voltage range is V
+
− 1.5V, but either or both inputs can go to 32V without damage (26V for LM2924).
Note 9:
Due to proximity of external components, insure that coupling is not originating via the stray capacitance between these external parts. This typically can be
detected as this type of capacitive increases at higher frequencies.
Note 10:
Positive excursions of input voltage may exceed the power supply level. As long as the other input voltage remains within the common-mode range, the
comparator will provide a proper output state. The input voltage to the op amp should not exceed the power supply level. The input voltage state must not be less
than −0.3V (or 0.3V below the magnitude of the negative power supply, if used) on either amplifier.
Note 11:
The response time specified is for a 100 mV input step with 5 mV overdrive. For larger overdrive signals 300 ns can be obtained.
Schematic Diagram
DS007793-2
Application Hints
Please refer to the application hints section of the LM193 and the LM158 datasheets.
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