DESCRIPTION

· The LM3914 is a monolithic integrated circuit that senses analog voltage levels and drives 10 LEDs, providing a linear analog display.

· It features a single pin that changes the display from a moving dot to a bar graph.

· The circuit includes its own adjustable reference and an accurate 10-step voltage divider.

· The low-bias-current input buffer accepts signals down to ground or V−, without needing protection against inputs of ±35V.

· The buffer drives 10 individual comparators referenced to the precision divider, ensuring indication non-linearity is typically held to ½% over a wide temperature range.

FEATURES

· Drives LEDs, LCDs, or Vacuum Fluorescents, easily added to the display system.

· Bar or Dot Display Mode externally selectable by the user.

· Expandable to displays of 100 steps, with both ends of the voltage divider externally available.

· Internal voltage reference from 1.2V to 12V, operates with a single supply of less than 3V.

· Inputs operate down to ground, with output current programmable from 2mA to 30mA.

· No multiplex switching or interaction between outputs, with LED driver outputs being current regulated.

· Outputs can interface with TTL or CMOS logic, and the internal 10-step divider is floating and can be referenced to a wide range of voltages.

APPLICATIONS

· The LM3914 is very easy to apply as an analog meter circuit, requiring only one resistor and a single 3V to 15V supply in addition to the 10 display LEDs.

· It can be used as a controller, visual alarm, and expanded scale functions.

· The circuit can drive LEDs of many colors or low-current incandescent lamps.

· Many LM3914s can be "chained" to form displays of 20 to over 100 segments.

· It can also act as a programmer or sequencer, with various effects achievable by modulating the currents.