IRPLHALO1E International Rectifier, IRPLHALO1E Datasheet - Page 7

• 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
This is provided that the correct value of current sense resistor has been selected for the maximum
rated load and line voltage supply of the convertor. This should be 0.33 Ohm (0.5W) for a 100W
system running from a 220-240V AC line. (It should be noted that the RCS resistor value is also
critical for setting the limits for the shut down circuit).
In run mode the oscillator frequency will vary from approximately 30kHz when VCSD is 5V (maxi-
mum load) to around 60kHz when VCSD is 0V (no load). The result of this is that at lighter loads, for
example if only a single 35W lamp is connected to a 100W convertor, the frequency will shift up-
wards so that the output voltage falls below the maximum that is acceptable for the lamp. This
provides sufficient compensation for the load to ensure that the lamp voltage will always be within
acceptable limits but does not require a complicated and expensive system involving feedback
from the output.
An additional internal current source has been included to discharge the external capacitor. This will
provide ripple at twice the line frequency if CSD is 100nF.
The advantage of this frequency modulation (or “dither”) is that during the line voltage half cycle the
oscillator frequency will vary by several kHz, thus spreading the EM conducted and radiated emis-
sions over a range of frequency and avoiding high amplitude peaks at certain frequencies. In this
way the filter components used may be similar to those used in a common bipolar self-oscillating
system.
Shut Down operation
The IR2161 contains a dual mode auto-resetting shutdown circuit that detects either a short circuit
or overload condition at the output. The load current detected at the CS pin is used to sense these
conditions. If the output of the convertor is short-circuited, a very high current will flow in the half
bridge and the system must shut down within a few mains half cycles otherwise the MOSFETs will
rapidly be destroyed due to excessive die temperature. The CS pin has an internal threshold of ap-
proximately 1.0V so that if the voltage exceeds this level for more than 50mS the system will shut down.
A delay is included to prevent false tripping either due to lamp inrush current at switch on (this
current is still higher than normal with the soft start operation) or transient currents that may occur if
an external triac based phase cut dimmer is being used.
There is also a lower threshold of 0.5V, which has a much longer delay before it shuts down the
system. This provides the overload protection if an excessive number of lamps is connected to the
output or the output is short-circuited at the end of a length of cable that has sufficient resistance to
prevent the current from being large enough to trip the short circuit protection. Under this condition
there is also an excessive current in the half bridge that is sufficient to cause heating and eventual
failure but over a longer period of time. The threshold for overload shutdown is approximately 50%
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