FA5546 Datasheet, PDF (5/27 Pages) Fuji Electric – Switching Power Supply Control IC

FA5546/47
4. Block diagram
FA5546 (Overload protection : Auto recovery type)
Start up
VH
Current
ON
UVLO
-
+
5V Reg.
OFF
Reset
Internal Power Supply
Reset
OSC Dmax
VCC
30V
DBL
OUTPUT
OUT
Freq control
1shot
input
CLR
RSFF
OFF(FB)
SQ
5V
-
R
+
FB
×
INV. AMP
Lv. Shift
IS
IS comp.
+
+
-
OFF (IS)
+
-
Start up
Management
Logic
VCC
Monitor Ctrl
ON
LAT
GND
Brownout
+
Brown out BO
-
Timer
- ^OLP
+
T1
Ctrl
T2
OLP Timer
VCC _{+ OVP}
5V
-
T1:Delay time to OLP-stop
T2:Time to OLP-stop
LAT
-
+
Latch _Latch
Set
UVLO
Reset
Over Load
BO
Latch
FA5547 (Overload protection : Latch shutdown type)
Start up
VH
Current
ON
UVLO
-
+
5V Reg.
OFF
Reset
Internal Power Supply
Reset
OSC Dmax
VCC
30V
DBL
OUTPUT
OUT
Freq control
1shot
input
CLR
RSFF
OFF(FB)
SQ
5V
-
R
+
FB
×
INV. AMP
Lv. Shift
IS
IS comp.
+
+
-
OFF (IS)
+
-
Start up
Management
Logic
VCC _{Monitor Ctrl}
ON
LAT
GND
Brownout
+
Brown out BO
-
Timer
- ^OLP
+
T1
Ctrl
T2
OLP Timer
Over Load
VCC _{+ OVP}
5V
-
T1:Delay time to OLP-Latch
BO
LAT
-
+
Over Load
Latch _Latch
Set
UVLO
Reset
Latch
Fuji Electric Co., Ltd.
AN-027E Rev.0.4
April -2011
5
http://www.fujielectric.co.jp/products/semiconductor/