How LM3914 IC works?
The LM3914 is a monolithic integrated circuit that senses analog voltage levels and drives 10 LEDs, providing a linear analog display. A single pin changes the display from a moving dot to a bar graph. Current drive to the LEDs is regulated and programmable, eliminating the need for resistors.
What is dot mode and display mode?
The Mode pin allows you to select between “bar” mode and “dot” mode. In bar mode, all LEDs sequentially turn on. So, if the signal voltage is near max, all LEDs should be on. In “dot” mode just a single LED is on at any time.
What are two modes of LEDs the LM3914 can control and how?
The analog input voltage can vary from 3V to 18V and the LED current can be limited by simply using a single resistor on pin 7 (Ref Out). The IC also has two operating modes DOT mode and BAR mode, also more than one IC can be cascaded to control upto 100 LEDs.
What is the maximum output current of LM3914 IC?
The LM3914 is relatively low-powered itself, and since any number of LEDs can be powered from about 3V, it is a very efficient display driver. Typical standby supply current (all LEDs OFF) is 1.6mA (2.5mA max).
How does a LM3915 work?
LM3915 is a dot/bar display driver which drives a series of LEDs based on the analog input. It basically drives each adjacent LED in 3DB steps i.e.in logarithmic way. It operates from a supply voltage of 3 V to 25 V. Pins 1, 10 to 18: Each of these pins is connected to the cathode of the output LED.
What is the difference between LM3914 and LM3915?
The LM3914 / LM3915 / LM3916 are identical except for the ten resistor divider inside each part. LM3915 – 3dB logarithmic steps, scaled by a resistor divider consisting of 6630, 4690, 3310, 2340, 1660, 1170, 830, 590, 410, 1000 ohm resistors.
What is VU meter in audio?
VU is an abbreviation for volume unit. Thus, a VU meter is a device for measuring the level of SOUND INTENSITY with audio equipment, such as AMPLIFIERs and TAPE RECORDERs.