IR21571 Datasheet, PDF (1/17 Pages) International Rectifier – FULLY INTEGRATED BALLAST CONTROL IC

Data Sheet PD No. 60179-I
IR21571^(S)
FULLY INTEGRATED BALLAST CONTROL IC
Features
• ^{Programmable preheat time & frequency}
• ^{Programmable ignition ramp}
• ^{Protection from failure-to-strike}
• ^{Lamp filament sensing & protection}
• ^{Protection from operation below resonance -}
0.2V CS threshold sync’d to falling edge on LO
• ^{Protection from low-line condition}
• ^{Automatic restart for lamp exchange}
Description
• ^{Thermal overload protection}
• ^{Programmable deadtime}
• ^{Integrated 600V level-shifting gate driver}
• ^{Internal 15.6V zener clamp diode on VCC}
• ^{Micropower startup (150uA)}
• ^{Latch immunity protection on all leads}
• ^{ESD protection on all leads}
Packages
The IR21571 is a fully integrated, fully protected 600V ballast control IC designed to
drive virtually all types of rapid start fluorescent lamp ballasts. Externally program-
mable features such as preheat time & frequency, ignition ramp characteristics, and
running mode operating frequency provide a high degree of flexibility for the ballast
design engineer. Comprehensive protection features such as protection from failure of
a lamp to strike, filament failures, low dc bus conditions, thermal overload, or lamp
failure during normal operation, as well as an automatic restart function, have been
included in the design. The heart of this control IC is a variable frequency oscillator
with externally programmable deadtime. Precise control of a 50% duty cycle is accom-
plished using a T-flip-flop. The IR21571 is available in both 16 pin DIP and 16 pin narrow
body SOIC packages.
16 Lead SOIC
(narrow body)
16 Lead PDIP
Typical Connection
+ Rectified AC Line
+ V_BUS
R2
R1
C1
C_PH
C_RAMP R_PH
R_T
R_RUN
C_START R_START
C_T
R_OC
R_DT
VDC
1
CPH
2
RPH
3
RT
4
RUN
5
CT
6
DT
7
OC
8
HO
16
VS
15
VB
14
VCC
13
COM
12
LO
11
CS
10
SD
9
R_Supply
R_GHS
C_BS
D_BOOT
C_VCC
R3 ^RGLS
R4
C2 R_CS
C_BLOCK L_RES
C_SNUBBER
D1
D2
R5
C_RES
V_BUS return
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