This is the circuit for bar mode using LM3914 IC for great expanded scale. This circuit is very simple design. This circuit is only consists of some resistors circuit. This is the figure of the circuit.
Placing the LM3914 internal resistor divider in parallel with a section (.230Ω) of a stable, low resistance divider greatly reduces voltage changes due to IC resistor value changes with temperature. Voltage V1 should be trimmed to 1.1V first by use of R2. Then the voltage V2 across the IC divider string can be adjusted to 200mV, using R5 without affecting V1. LED current will be approximately 10mA. [Schematic source: National Semiconductor, Inc].
Placing the LM3914 internal resistor divider in parallel with a section (.230Ω) of a stable, low resistance divider greatly reduces voltage changes due to IC resistor value changes with temperature. Voltage V1 should be trimmed to 1.1V first by use of R2. Then the voltage V2 across the IC divider string can be adjusted to 200mV, using R5 without affecting V1. LED current will be approximately 10mA. [Schematic source: National Semiconductor, Inc].
how to calculate resistor values for voltages other than those shown in the datasheet examples ?
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