IRPLHALO1E International Rectifier, IRPLHALO1E Datasheet - Page 14

• Manufacturer Part Number: IRPLHALO1E
• Description: KIT HALOGIN CONVERTER 100VA
• Manufacturer: International Rectifier

Specifications of IRPLHALO1E

• Main Purpose: Lighting, Ballast Control
• Utilized Ic / Part: IR2161
• Lead Free Status / RoHS Status: Lead free / RoHS non-compliant
• Secondary Attributes: -
• Embedded: -
• Primary Attributes: -
• Other names: *IRPLHALO1E

IRPLHALO1E
In the event of the voltage at the half bridge failing to slew all the way down to COM the adaptive
dead time circuit will time out after 1 to 1.5uS and switch on the relevant MOSFET thus operating
with hard switching. This could happen during the first few cycles after start up. It should never be
the case in normal running conditions unless the load is very light or the primary leakage induc-
tance is excessive or that an unnecessarily large snubber capacitor is present.
This system avoids the need for an external resistor to program the dead time and contributes with
the multi functional nature of CSD to the IR2161 being realized with only 8 external pins.
Dimming
DC BUS VOLTAGE
Almost any Halogen convertor available can be dimmed
by an external phase cut dimmer that operates in trailing
edge mode. This means that at the beginning of the line
voltage half cycle voltage the switch inside the dimmer is
closed and mains voltage is supplied to the convertor al-
LAMP VOLTAGE
lowing the convertor to operate normally. At some point
during the half cycle the switch inside the dimmer is opened
and voltage is no longer applied. The DC bus inside the
convertor almost immediately drops to 0V and the output
is no longer present. In this way bursts of high frequency
output voltage are applied to the lamp. The RMS voltage
across the lamp will naturally vary depending on the
phase angle at which the dimmer switch switches off. In this
Fig. 5 Trailing Edge Dimming
way the lamp brightness may easily be varied from zero to maximum output.
Trailing edge dimmers are less common however than
leading edge dimmers. This is because they are more
expensive to make and need to incorporate a pair of
DC BUS VOLTAGE
MOSFETs or IGBTs whereas a leading edge dimmer is
based around a single triac.
Conversely many Halogen convertors are not able to op-
erate with leading edge dimmers because of the fact that
LAMP VOLTAGE
they are based around a triac. It is possible however to
design a Halogen convertor that will work effectively with
a triac based dimmer by paying attention to design the
input filter components correctly and to ensure that at the
firing point of the triac the oscillator will start up rapidly. In
the IR2161 based system this is easy to achieve through
the addition of RD and CD which conduct a large current
Fig. 6 Leading Edge Dimming
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