ISL1902 Datasheet, PDF (4/25 Pages) Intersil Corporation – Full-Featured, Dimmable AC Mains LED Driver with PFC

Functional Block Diagram - ISL1902
VREF
VDD
GND
UVLO
+
-
OTP Shutdown
BG
150 - 170 °C
Bias and
Reference
Generator
BIAS/UVLO/OTP
INRUSH CONTROL CIRCUIT
DELAYED AC-P
Q
Q
150us
One Shot
AC Present 0-Xing
Blanking
Q
Q
350 μS
One Shot
LPOUT
AC
PRELOAD
OFFREF
IOUT
CS-
CS+
REFIN
DELADJ
OC
RAMP
DUTY CYCLE TO
VOLTAGE
CONVERTER
LOW PASS FILTER
Master
CLK
Oscillator
Peak
REF
DetecAtoCr
DETECTION
-
+
AC-PRESENT
DIFFERENTIAL ISENSE
-
IOUT
+
No AC Counter
MINIMUM DIMMING
LEVEL CONTROL
CLK
CARRY
-
+
INHIBIT
Triangle Wave
Generator
CLK
DIMMING PWM
-
+
REFINBUFF
+
+
_
Reference SS
Buffer
-
+
CrCM
DETECTOR
Quasi-ZVS
Delay
fMAX
Clamp
fMIN
Clamp
Leading
Edge
Blanking
+
600 mV -
PRIMARY OC
200mV
Verr/5 SS/5
+
-
-
PWM
COMPARATOR
1/5
1/5
EA1
+
-
+
EA2
-
SQ
RQ
PWM LATCH
CrCM OSCILLATOR/PWM/ERROR
AMPLIFIERS
PWM
SS
REFINBUFF
VERR
VERR
FB2 FB1
VREF
+
-
LINEAR AMPLIFIER
INHIBIT
Reference SS
VERR CLAMP
-
+
SOFT-START/POR/OVP
+
- 1.50 V
SS
ENABLE
300 ms
Soft Start
SS LOW +
-
0.25 V
FAULT LATCH
SQ
RQ
INRUSH
LREF
LOUT
LFB
PWMOUT
OUT
OVP