LM3915 LED Dot/Bar Display Driver IC

LM3915 is a monolithic integrated circuit that drives a 10 segment LED bar and dot matrix. It is commonly used to visualize audio signals. It provides 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 power supply as low as 3V or as high as 25V.

Features

• 3 dB/step, 30 dB range
• Drives LEDs, LCDs, or vacuum fluorescents
• Bar or dot display mode externally selectable by the user
• Expandable to displays of 90dB
• Internal voltage reference from 1.2V to 12V
• Operates with a single supply of 3V to 25V
• Inputs operate down to the 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-steps divider is floating and be referenced to a wide range of voltages

Specification

• Maximum supply voltage: 25V
• Voltage on output drivers: 25V
• Input signal over-voltage: ±35V
• Divider voltage: -100mV to V+
• Reference load current: 10 mA
• Power dissipation: 1365 mW
• Storage temperature range: -55℃ to +150℃

Application

• Audio visualization circuit
• Crude battery level indicator
• Fade bars