LM3914 Datasheet, PDF (10/19 Pages) National Semiconductor (TI) – Dot/Bar Display Driver

Typical Applications (Continued)
Expanded Scale Meter, Dot or Bar
DS007970-8
*This application illustrates that the LED supply needs practically no filtering
Calibration: With a precision meter between pins 4 and 6 adjust R1 for voltage V_D of 1.20V. Apply 4.94V to pin 5, and adjust R4 until LED No. 5 just lights.
The adjustments are non-interacting.
Application Example:
Grading 5V Regulators
Highest No.
LED on
10
9
8
7
6
5
4
3
2
1
Color
Red
Red
Yellow
Green
Green
5V
Green
Green
Yellow
Red
Red
V_OUT(MIN)
5.54
5.42
5.30
5.18
5.06
4.94
4.82
4.7
4.58
4.46
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