LM3915N

LM3915 www.ti.com SNVS740C – JANUARY 2000 – REVISED MARCH 2013 LM3915 Dot/Bar Display Driver Check for Samples: LM3915 FEATURES 1 2 3 dB/step, 30 dB Range Drives LEDs, LCDs, or Vacuum Fluorescents Bar or Dot Display Mode Externally Selectable by User Expandable to Displays of 90 dB Internal Voltage Reference from 1.2V to 12V Operates with Single Supply of 3V to 25V Inputs Operate Down to Ground Output Current Programmable from 1 mA to 30 mA Input Withstands ±35V without Damage or False Outputs Outputs are Current Regulated, Open Collectors Directly Drives TTL or CMOS 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 18lead PDIP Package. 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 highimpedance input buffer accepts signals down to ground and up to within 1.5V of the positive supply. Further, it needs no protection against ...