Connection Diagram
Dual-in-Line Package
DS005104-32
Top View
Order Number LM3915N-1
See NS Package Number NA18A
*
Order Number LM3915N
See NS Package Number N18A
Discontinued, Life Time Buy date 12/20/99
*
sured at the current source outputs. As the forward voltage
Definition of Terms
of an LED does not change significantly with a small change
in forward current, this is equivalent to changing the voltage
at the LED anodes by the same amount.
Absolute Accuracy: The difference between the observed
threshold voltage and the ideal threshold voltage for each
comparator. Specified and tested with 10V across the inter-
nal voltage divider so that resistor ratio matching error pre-
dominates over comparator offset voltage.
Line Regulation: The average change in reference output
voltage (VREF) over the specified range of supply voltage
(V+).
Adjust Pin Current: Current flowing out of the reference ad-
just pin when the reference amplifier is in the linear region.
Load Regulation: The change in reference output voltage
over the specified range of load current (IL(REF)).
Comparator Gain: The ratio of the change in output current
(ILED) to the change in input voltage (VIN) required to pro-
duce it for a comparator in the linear region.
Offset Voltage: The differential input voltage which must be
applied to each comparator to bias the output in the linear re-
gion. Most significant error when the voltage across the in-
ternal voltage divider is small. Specified and tested with pin
6 voltage (VRHI) equal to pin 4 voltage (VRLO).
Dropout Voltage: The voltage measured at the current
source outputs required to make the output current fall by
%
10
.
Relative Accuracy: The difference between any two adja-
cent threshold points. Specified and tested with 10V across
the internal voltage divider so that resistor ratio matching er-
ror predominates over comparator offset voltage.
Input Bias Current: Current flowing out of the signal input
when the input buffer is in the linear region.
LED Current Regulation: The change in output current over
the specified range of LED supply voltage (VLED) as mea-
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