The LM3914 is an amazing analog - controlled LED driver for dot/bar displays using a linear output scale. With just one analog signal, it can drive a string of 10 or more LEDs. You can easily switch between bar mode (where LEDs below a certain level light up) and dot mode (with only one LED on at a time). This makes it super handy for creating all kinds of cool multi - LED displays.
Applying the LM3914 as an analog meter circuit is a breeze. For a 1.2V full - scale meter, you only need 1 resistor, a single 3V to 15V power supply, and the 10 display LEDs. If you use a potentiometer as the resistor, you can control the LED brightness. The simplified block diagram shows how simple the external circuitry is.
**Features**:
- Can drive LEDs, LCDs, or Vacuum Fluorescents.
- You can externally choose between bar or dot display mode.
- It can be expanded to 100 - step displays.
- Has an internal voltage reference from 1.2V to 12V.
- Works with a single supply of less than 3V.
- Outputs can connect with TTL or CMOS Logic.
**Documents**:
- Datasheet
- Hookup Guide
- Product Video
Using the LM3914 is straightforward. First, connect your power supply. It can work with a single supply of less than 3V. Then, connect the 10 or more LEDs. With a single analog signal, you can start driving these LEDs. You can decide whether to use bar mode or dot mode according to your needs. Just hook up the external pins as per the hookup guide.
When using it as an analog meter circuit, for a 1.2V full - scale meter, add a single resistor and the power supply. If you want to control the LED brightness, use a potentiometer as the resistor.
As for maintenance, keep the device in a dry and cool place. Make sure the power supply is stable to avoid damage to the internal voltage reference. If you have any problems, refer to the datasheet or the product video for more detailed information.
