IR21593 International Rectifier, IR21593 Datasheet - Page 22

• Manufacturer Part Number: IR21593
• Description: IC CTRLR BALLAST DIMMING 16-DIP
• Manufacturer: International Rectifier
• Type: Ballast Controllerr

Specifications of IR21593

• Frequency: 30 ~ 230 kHz
• Current - Supply: 10mA
• Voltage - Supply: 12.5 V ~ 15.6 V
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 16-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Current - Output: -
• Other names: *IR21593

IR21592/IR21593
Ballast Output Stage
The components comprising the output stage are
selected using a set of equations. Different ballast
operating frequencies and their respective
voltages and currents are calculated.
The inductor and capacitor values are obtained
using equations (2) through (7). The results of
these equations reveal the location of each
operating frequency and the corresponding
voltages and currents. For a given L, C, DC bus
voltage, and pre-heat current, the resulting voltage
over the lamp during pre-heat is given as:
The resulting operating frequency during pre-heat
is given as:
The resulting operating frequency during ignition
is given as:
The total load current during ignition is given as:
22
V
I
ph
ign
f
f
ign
ph
2
f
1
2
ign
V
CV
2
DC
CV
I
1
ph
ph
ign
LC
2
4
V
V
2
ign
DC
8
C
L
I
ph
2
1
2
( S ) & ( PbF )
[Hz]
[App] (5)
[Hz]
2
V
DC
(4)
(3)
The cathode heating current at minimum lamp
power is given as:
Design Constraints
The inductor and capacitor values should be
iterated until the following design constraints have
been fulfilled (Table II).
In order to program the MIN and MAX settings of
the dimming interface, the phase of the output
stage current at minimum and maximum lamp
power must be calculated. This is obtained using
the following equations:
The operating frequency [Hz] at maximum lamp
power is given as:
IR21592/IR21593 Programmable Inputs
f
100
%
I
Cath
2
f
I
1
Design Constraint
ph
Cath
V
1
I
%
ign
ph
LC
1
Table II, Ballast design constraints
1
%
f
ign
V
I
C
V
32
ign
I
2
ph
1
V
P
Cath
100
%
100
2
max
max
4
5
%
%
kHz
f
min
1
2
%
LC
C
1
Ignition during pre-
heat
Production tolerances
Inductor saturation
Lamp
during dimming
C
32
2
V
P
100
100
2
4
%
%
Reason
extinguishing
2
1
www.irf.com
L
V
4
2
100
C
V
DC
%
2
2
(7)
(6)