IRS2158DSTRPBF International Rectifier, IRS2158DSTRPBF Datasheet - Page 25

• Manufacturer Part Number: IRS2158DSTRPBF
• Description: IC BALLAST CTRL 600V 16-SOIC
• Manufacturer: International Rectifier
• Type: Fluorescent Lamp Driverr

Specifications of IRS2158DSTRPBF

• Frequency: 42.5 ~ 48.5 kHz
• Current - Supply: 3.5mA
• Current - Output: 260mA
• Voltage - Supply: 11.5 V ~ 15.6 V
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 16-SOIC (3.9mm Width)
• For Use With: IRPLDIM3 - KIT DES FLUOR BALLAST IRS2158D
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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Step 5: Program Ignition Ramp Time
The preheat time is defined by the time it takes for the external capacitor on pin VCO to charge up to 5V.
The external timing resistor (RPH) connected to FMIN charges capacitor CVCO. The ignition ramp time is
therefore given as:
Step 6: Program Maximum Ignition Current
The maximum ignition current is programmed with the external resistor RCS and an internal threshold of
1.2V. This threshold determines the over-current limit of the ballast, which will be reached when the
frequency ramps down towards resonance during ignition and the lamp does not ignite. The maximum
ignition current is given as:
or
VCC Double Filter
It is recommended to utilize a double filter arrangement from the charge pump (CSNUB, DCP1 and DCP2)
to VCC as shown in the schematic of Figure 9. This circuit is designed to protect the VCC supply pin of the
IRS2158D from high peak currents that occur when the MOSFET MHS switches VS from COM to VBUS.
DCP2 should be an 18 V rated zener diode and RSUPPLY should connect to the cathode of DCP2. This is
to protect the VCC input of the IRS2158D from possible surges and transient voltages.
I
R
IGN
CS
=
=
1
R
I
1
IGN
2 .
CS
2 .
C
C
Figure 9: VCC Double Filter Arrangement
VCO
[Amps Peak]
PH
[Ohms]
t
RAMP
=
=
R
t
t
R
CPH
PH
RAMP
=
PH
R
PH
⋅
C
(11)
VCO
(10)
25
or
[Seconds] (8)
[Farads]
[Farads]
(7)
(9)
© 2009 International Rectifier
IRS2158D(S)