IRS21571DSPBF International Rectifier, IRS21571DSPBF Datasheet - Page 21

• Manufacturer Part Number: IRS21571DSPBF
• Description: IC BALLAST CTRL 600V 16-SOIC
• Manufacturer: International Rectifier
• Type: Ballast Controllerr

Specifications of IRS21571DSPBF

• Frequency: 43.7 ~ 48.3 kHz
• Current - Supply: 10mA
• Current - Output: 180mA
• Voltage - Supply: 11.5 V ~ 15.6 V
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 16-SOIC (0.154", 3.90mm Width)
• Package: 16-lead SOIC Narrow
• Circuit: Fluorescent Ballast IC
• Offset Voltage (v): 600
• Output Source Current Min (ma): 180
• Output Sink Current Min (ma): 260
• Pbf: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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When the SD pin exceeds 2.0V (approximately 150mV of hysterisis is included to increase noise immunity),
signaling either a lamp fault or lamp removal, the oscillator is disabled, both gate driver outputs are pulled low,
and the chip is put into the micropower mode. Since a lamp fault would normally lead to a lamp exchange, when
a new lamp is inserted into the fixture, the SD pin would be pulled back to near the ground potential. Under these
conditions a reset signal would restart the chip from the beginning of the control sequence, as shown in the timing
diagram in Figure 13.
Thus, for a lamp removal and replacement, the ballast automatically restarts the lamp in the proper manner,
maximizing lamp life and minimizing stress on the power MOSFETs or IGBTs.
VDC
CPH
RPH
RUN
OC
RT
CT
DT
SD
CT
CPH
LO
HO-VS
Figure 12: Lamp presence detection circuit
1
2
3
4
5
6
7
8
Figure 13: SD pin fault and auto restart
2
15
15
4
8
16
15
14
13
12
11
10
9
connection (shaded area)
RUN mode
VCC
COM
HO
VS
VB
CS
SD
LO
+ rectified
AC Line
R
C
D
C
GHS
R3
BS
BOOT
VCC
C2
R4
R
GLS
V
R
BUS
Supply
R
21
CS
SD mode
+ V
return
BUS
R5
D1
C
C
D2
BLOCK
SNUBBER
Restart
L
RES
C
RES
© 2008 International Rectifier
IRS21571D