IRPLLNR4 International Rectifier, IRPLLNR4 Datasheet - Page 8

• Manufacturer Part Number: IRPLLNR4
• Description: BALLAST UNIV INP FLUOR IR2166
• Manufacturer: International Rectifier

Specifications of IRPLLNR4

• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: *IRPLLNR4

Demo board Overview
This demo-board is designed for single TL5/35W Lamp, voltage mode heating (JV1 and JV2 mounted,
JC1 and JC2 not mounted). TL5 lamps are becoming more popular due to their lower profile and
higher lumen/ watt output. These lamps, however, can be more difficult to control due to their higher
ignition and running voltages. A typical ballast output stage using current-mode filament heating
(filament placed inside L-C tank) will result in excessive filament current during running. The output
stage has therefore been configured for voltage-mode filament heating using secondary windings off
of the resonant inductor LRES. The lamp has been placed outside the under-damped resonant circuit
loop, which consist of LRES and CRES. The filament heating during preheat can be adjusted with the
capacitors CH1 and CH2. The result is a more flexible ballast output stage necessary for fulfilling the
lamp requirements. The DC blocking capacitor, CDC, is also placed outside the under-damped
resonant circuit loop such that it does not influence the natural resonance frequency of LRES and
CRES. The snubber capacitor, CSNUBB, serves as charge pump for supplying the IR2166.
The IR2166 Ballast Control IC is used to program the ballast operating points and protect the ballast
against conditions such as lamp strike failures, low DC bus, thermal overload or lamp failure during
normal operations. It is also used to regulate the DC bus and for power factor control allowing high
power factor and low harmonic distortion.
Power Factor Correction Section
The power factor correction section contained in the IR2166 forms the control for a boost topology
circuit operating in critical conduction mode. This topology is designed to step-up and regulate the
output DC bus voltage while drawing sinusoidal current from the line (low THD) which is “in phase”
with the AC input line voltage (HPF).
Ballast Control Section
The ballast control section of the IR2166 Ballast Control IC contains an oscillator, a high voltage half-
bridge gate driver and lamp fault protection circuitry. Please, refer to the datasheet of this IC for the
block diagram and the state diagram. Following is a breakdown of the operation of the ballast in all of
the different modes of operation.
Startup Mode
When power is initially applied to the ballast, the voltage on the VCC pin of the IR2166 begins to
charge up. The voltage for the IR2166 is derived from the current supplied from the rectified AC line
through startup resistor RSUPPLY. During this initial startup when the VCC voltage of the IR2166 is
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