Part Number: LM3915, LM3915N
Function : Dot / Bar Display Driver
Package: DIP 18 Pin type
Manufacturer: National Semiconductor, TI
Image
Description
The LM3915 is a monolithic integrated circuit that senses analog voltage levels and drives ten LEDs, LCDs or vacuum fluorescent displays, providing a logarithmic 3 dB/step analog display. One pin changes the display from a bar graph to a moving dot display. LED current drive is regulated and programmable, eliminating the need for current limiting resistors. The whole display system can operate from a single supply as low as 3V or as high as 25V. The IC contains an adjustable voltage reference and an accurate ten-step voltage divider. The high-impedance input buffer accepts signals down to ground and up to within 1.5V of the positive supply. Further, it needs no protection against inputs of ±35V. The input buffer drives 10 individual comparators referenced to the precision divider. Accuracy is typically better than 1 dB.
Pinout
Features
1. 3 dB/step, 30 dB range
2. Drives LEDs, LCDs, or vacuum fluorescents
3. Bar or dot display mode externally selectable by user
4. Expandable to displays of 90 dB
5. Internal voltage reference from 1.2V to 12V
6. Operates with single supply of 3V to 25V
7. Inputs operate down to ground
8. Output current programmable from 1 mA to 30 mA
Typical Applications
Reference Site: https://en.wikipedia.org/wiki/LM3914