LM3915 / LM3914 10 Segment Led dot / bar display driver ic

LM3915 / LM3914 are 10-segment dot/bar display driver ICs designed to sense analog voltage levels and drive LEDs, LCDs, or vacuum fluorescent displays. These ICs integrate precision comparators, an internal voltage reference, and a resistor divider network, enabling accurate and stable visual indication with minimal external components. LM3915 provides a logarithmic scale (3 dB per step), while LM3914 provides a linear scale for direct voltage measurement applications.

Configuration:
10-step display driver (LM3915 logarithmic, LM3914 linear)
Selectable display mode: dot or bar
Through-hole package (DIP-18)
Expandable by cascading multiple ICs

Electrical Characteristics:
Supply voltage: 3 V to 25 V (single supply)
Internal reference voltage: adjustable from 1.2 V to 12 V
Output current: programmable from ~2 mA to 30 mA
Input voltage range: from ground to (V+ − 1.5 V)
Input overvoltage protection: up to ±35 V
LM3915 scale: 3 dB per step (30 dB range)
LM3914 scale: linear voltage steps

Construction:
Internal precision 10-step resistor divider
10 comparators for level detection
Current-regulated open-collector outputs
High-impedance input buffer
Integrated adjustable voltage reference

Configuration Notes:
Bar or dot mode selectable via mode pin
LED current is internally regulated (no external resistors required)
LED brightness adjustable using reference current
Devices can be cascaded to extend display range (20 to 100 segments)
Outputs can interface with TTL or CMOS logic

Intended Use:
Audio level indicators (VU meters)
Signal strength meters
Power and voltage level displays
Process monitoring indicators
General-purpose analog display systems