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Fluorescent Lighting Technology

At the forefront of the most efficient incandescent alternatives are LED and Fluorescent technologies. Both have advantages and technical challenges and provide significantly improved efficacy (lumens/watt) over incandescent lighting. Additionally both technologies provide opportunities to add intelligence beyond simple incandescent light bulb replacement.


  • Relatively Inexpensive
  • Good Efficiency
    • ~75% less energy than incandescent
    • ~25% input energy = light
    • More than 70++ lumens/watt (efficacy)
  • Long Life: >20,000 hours


  • Requires ballast to initiate & maintain electrical reaction
  • Typically requires “warm-up”
  • Can contain mercury
  • Sensitive to environment & orientation

Variations (Gas Discharge & Arc Lamps)

  • Fluorescent, CFL, HID, Low/High Pressure Sodium,
  • Induction, Neon, Xenon, Mercury Vapor, Metal Halide

Typical fluorescent lighting operates by driving a current through a glass enclosure containing an inert gas along with mercury – and with the help of phosphors, create visible light when excited by electricity. Arc lamps are similar in function but create visible light through electrically excited gases (plasma) without the use of phosphors. Whether its gas-discharge or arc lamps – a ballast is required to initiate and maintain this electrical reaction.

A Microchip based solution can provide these capabilities and more…

Controlling a Fluorescent Source

The ballast kick-starts the electrical-gas reaction with a large amount of energy and then regulates the current back down to a normalized operating current. To accurately control this reaction as well as provide smooth dimming control – high resolution PWM frequency control is required.


To learn more about PWM variants - visit Focus Peripherals

Efficient Power Conversion

Microchip based solutions can provide accurate lighting and dimming control as well as add additional capabilities beyond that of traditional lighting solutions. The flexibility of these solutions allows for simplified attachment to existing designs or the development of full Switch Mode Power Supply (SMPS) based intelligent solutions.

PIC MCU attach to basic power supply

  • Simplified design-in
  • Customizable features
  • Simplified modifications via firmware updates
  • Intelligent Control Capabilities

SMPS with PIC MCU & Microchip Analog

  • Increased MCU integration
  • Fully Customizable
  • Increased Efficiency
  • Power Factor Correction (PFC)
  • Flexible Topologies
  • Simplified modifications via firmware updates
  • Closed loop control feedback
  • High performance PWM and current control variation
  • Intelligent Control Capabilities

The SMPS topologies utilized to regulate the power within lighting applications are the same used within a power supply application. Each SMPS topology has its advantages and determining the proper topology is dependent upon the specific application requirements. Reference the table for topology guidelines ...

Common Power Conversion Topologies

General SMPS Guidelines

TopologyVin vs. Vout RelationshipPower Range (max)Peak Efficiency
BuckVin > Vout1000W>90%
BoostVin < Vout150W>90%
Buck/BoostVout < Vin < Vout150W>80%
SEPIC, Cuk, ZetaVout < Vin < Vout150W>90%
FlybackVout < Vin < Vout150W>80%
ResonantVout < Vin < Vout500W>90%
Push-PullVout < Vin < Vout1KW>90%


Intelligent Control Capabilities

In addition to efficient power conversion and LED control, a Microchip based lighting solution provides opportunities to further enhance your lighting application through product differentiation and increased user experience.

  • Custom User Interface & Control
  • Communication & Networking
  • Environmental Sensing
    • Motion, External Light Source, etc.
  • Auto-Dimming
  • Smooth Dimming Control
  • System Health Monitoring
  • Predictive Failure Monitoring
  • Remote Fault Detection
  • Auto-Dimming
  • Smooth Dimming Control
  • System Health Monitoring
  • Predictive Failure Monitoring
  • Remote Fault Detection