LM3915N-1/NOPB National Semiconductor, LM3915N-1/NOPB Datasheet
LM3915N-1/NOPB
Specifications of LM3915N-1/NOPB
*LM3915N-1/NOPB
LM3915N-1
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LM3915N-1/NOPB Summary of contents
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... Directly drives TTL or CMOS n The internal 10-step divider is floating and can be referenced to a wide range of voltages The LM3915 is rated for operation from 0˚C to +70˚C. The LM3915N-1 is available in an 18-lead molded DIP package. DS005104 February 2001 ± 35V without damage or false outputs ...
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Typical Applications Notes: Capacitor C1 is required if leads to the LED supply are 6" or longer. Circuit as shown is wired for dot mode. For bar mode, connect pin 9 to pin 3. V dissipation. www.national.com 0V to 10V ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Power Dissipation (Note 6) Molded DIP(N) Supply Voltage Voltage on Output Drivers Electrical Characteristics Parameter COMPARATOR Offset Voltage, Buffer and First Comparator Offset Voltage, Buffer and Any Other Comparator Gain (∆ ...
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Electrical Characteristics Parameter SUPPLY CURRENT Standby Supply Current (All Outputs Off) 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 ...
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Typical Performance Characteristics Supply Current vs Temperature Reference Voltage vs Temperature LED Current-Regulation Dropout Operating Input Bias Current vs Temperature 00510434 Current vs Temperature 00510436 LED Driver Saturation 00510438 5 00510435 Reference Adjust Pin 00510437 Voltage 00510439 www.national.com ...
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Typical Performance Characteristics Input Current Beyond Signal Range (Pin 5) LED Driver Current Regulation Common-Mode Limits www.national.com (Continued) 00510440 Total Divider Resistance 00510442 Output Characteristics 00510444 6 LED Current vs Reference Loading 00510441 vs Temperature 00510443 00510445 ...
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Block Diagram (Showing Simplest Application) 7 00510404 www.national.com ...
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Functional Description The simplified LM3915 block diagram is included to give the general idea of the circuit’s operation. A high input imped- ance buffer operates with signals from ground to 12V, and is protected against reverse and overvoltage signals. The ...
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Mode Pin Functional Description (Continued) DOT OR BAR MODE SELECTION The voltage at pin 9 is sensed by comparator C1, nominally + referenced to (V − 100 mV). The chip is in bar mode when pin 9 is above this ...
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Application Hints (Continued) Power dissipation, especially in bar mode should be given consideration. For example, with a 5V supply and all LEDs programmed the driver will dissipate over 600 mW. In this case a 7.5Ω resistor in ...
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Application Hints (Continued) D1, D2: 1N914 or 1N4148 FIGURE 3. Precision Full-Wave Average Detector D1, D2, D3, D4: 1N914 or 1N4148 CASCADING THE LM3915 To display signals dynamic range, multiple LM3915s can be easily ...
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Application Hints (Continued) in both the precision rectifier and the 30 dB gain stage. To extend this approach to get display, another amplification must be placed in the signal path ahead of the lowest ...
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Application Hints (Continued) the LED current will be at least 5 mA. R1 will typically be between 1 kΩ and 2 kΩ. To trim the reference voltage, vary R2. The circuit in Figure 8 shows how to add a LED ...
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Application Hints (Continued) < < 10V LED REF FIGURE 9. Independent Adjustment of Reference Voltage and LED Intensity for Multiple LM3915s The scheme in Figure 10 is useful when the reference and ...
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Typical Applications *Optional circuit for improved intensity matching at low currents. See text. FIGURE 10. Wide-Range Adjustment of Reference Voltage and LED Intensity for Multiple LM3915s FIGURE 11 10V Log Display with Smooth Transitions 00510419 15 00510418 www.national.com ...
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Typical Applications This application shows that the LED supply requires minimal filtering. *See Application Hints for optional Peak or Average Detector. † Adjust R3 for 3 dB difference between LED #11 and LED #12. LED Threshold ...
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Typical Applications (Continued) Indicator and Alarm, Full-Scale Changes Display from Dot to Bar *The input to the dot bar switch may be taken from cathodes of other LEDs. Display will change to bar as soon as the LED so selected ...
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Typical Applications ± R7 thru R15: 10k 10% D1, D2: 1N914 or 1N4148 *Half-wave peak detector. See Application Hints. Supply current drain is only 15 mA with ten LEDs illuminated. www.national.com (Continued) Driving Vacuum Fluorescent Display Low Current Bar Mode ...
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Typical Applications (Continued) Full-scale causes the full bar display to flash. If the junction of R1 and C1 is connected to a different LED cathode, the display will flash when that LED lights, and at any higher input signal. Driving ...
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Typical Applications Logarithmic response allows coarse and fine adjustments without changing scale. Resolution ranges from 500 www.national.com (Continued) Precision Null Meter ± = 1.25V 00510428 ...
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Typical Applications (Continued) Operating with a High Voltage Supply (Dot Mode Only) The LED currents are approximately 10 mA, and the LM3915 outputs operate in saturation for minimum dissipation. *This point is partially regulated and decreases in voltage with temperature. ...
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Typical Applications Load Impedance 4Ω 8Ω 16Ω www.national.com (Continued) Audio Power Meter R1 10k 18k 30k 22 00510431 See Application Hints for optional Peak or Average Detector ...
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... Dual-in-Line Package 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 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 ...
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... Note: Unless otherwise specified. 1. Standard Lead Finish: 200 microinches /5.08 micrometer minimum lead/tin 37/63 or 15/85 on alloy 42 or equivalent or copper 2. Reference JEDEC registration MS-001, Variation AC, dated May 1993. www.national.com inches (millimeters) unless otherwise noted Molded Dual-In-Line Package (N) Order Number LM3915N-1 NS Package Number NA18A 24 ...
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... Deutsch Tel: +49 (0) 69 9508 6208 English www.national.com Français Tel: +33 ( 8790 Molded Dual-In-Line Package (N) Order Number LM3915N * NS Package Number N18A *Discontinued, Life Time Buy date 12/20/ critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system affect its safety or effectiveness ...