Design Your Circuit Part I – Display Driver


Use LM 3914 Integrated circuit to make an LED meter as Volt meter or Audio level indicator. Only a few discrete components are required to construct a Bar graph display in addition to this  IC.  LM 3914 / 3915 / 3916 version ICs are used in display circuits to drive either individual LED or Matrix LED. These are mainly used in circuits where precision output display is needed. Its each output becomes low one by one with the increment of 125 milli volts in its input. Let us see the details of its design.

Continue reading

Advertisements

Battery Level Meter


With this circuit, you can assess the voltage level in Lead Acid Car battery or Inverter battery. It gives LED indications in Dot Mode display to show the level of voltage in the battery. A Lead Acid battery attains 13.8 volts and tubular battery 14.8 volts in the fully charged state. If the battery voltage level drops below 10 volts, it needs immediate charging, and if it is not attaining full charge, it cannot be used to drive the load.

Continue reading

IC LM 3914 Design Note


LED displays are necessary to indicate audio levels, measurements and even for ornamental purposes. The simplest way to design an LED display is the circuit around the popular bar graph IC LM 3914. Only few discrete components are required to construct of Bar graph display. The note given here is useful to design the display driver using LM 3914 and its related versions.

Continue reading

IC LM 3914 Design Note


LED displays are necessary to indicate audio levels, measurements and even for ornamental purposes. The simplest way to design an LED display is the circuit around the popular bar graph IC LM 3914. Only few discrete components are required to construct of Bar graph display. The note given here is useful to design the display driver using LM 3914 and its related versions.

Continue reading

Stress Meter


This is my circuit published in Electronics for You magazine September 2005 issue. This Stress meter lets you assess your emotional pain.It gives audio visual indication when the stress level is too high. It is too small and can be wear on the wrist to monitor the Stress level
Circuit in PDF
stress meter

Bargraph Display


LM 3914 / 3915 / 3916 versions ICs are used in display circuits to drive either individual LED or Matrix LED. These are mainly used in circuits where precision output display is needed. Its each output becomes low one by one with the increment of 125 milli volts in the input. These ICs are used in Audio displays, Temperature meters, Decibel meters etc.

Continue reading