MIC4043 Datasheet, PDF (9/12 Pages) Micrel Semiconductor – Low-Voltage Secondary-Side Shunt Regulator

MIC4043
Off-Line 3.3V/2A Power Supply
85 to 264Vac
50/60Hz
Hot
F1
Ground
1A
Neutral
L1
20mH
C2
2200pF
400V
U2a
2501
C10
0.1µF
50/63V
U1
MIC38HC43BN
R5 _{1 COMP}
1.21k 1%
V_REF ⁸
2 _FB
R6
V_DD ⁷
1.21k
1%
3 _ISNS
V_OUT ⁶
4 _{RT/CT GND} 5
R7
14k 1%
C6
470pF
63V
R1
C7 1k 1%
470pF
63V
C1
0.1µF
250V
C3
2200pF
400V
R2
332k
1%
R3
332k
1%
R4
34Ω
1%
D2 C5
18V 0.1µF
50/
63V
BR1
DBR1
C4
47µF
400V
1
77T
2
D1
1N4448
4
C8
10T
22µF
25V
3
U2b
2501
C14 R10
3000pF 20k
50V 1%
U3
MIC4043
IN SNK
GND FB
D4
12CTQ045
R15
47.5k
1%
R12
90Ω
C13
1000pF
50/63V
R11
33k
1%
L2
V_OUT
+3.3V/2A
7
5µH
R14
3T
C11
1200µF
C12
220µF
200Ω
1%
6
10V
10V
Return
T1
V_TRIP
=
1.245V

R2
R1
+
1^{}
R13
10Ω 1%
Q1
IRFIBE30G
R8
1.0Ω
1/4W
1%
C9
100pF
1kV
R9
470Ω
1/2W
D3
UF4005
Figure 5. Off-Line 3.3V/2A Power Supply
Micrel
Figure 5a. 3.3V/1A Bode Plot
(θ margin = 76°)
Figure 5b. 3.3V/2A Bode Plot
(θ margin = 74°)
May 2000
9
MIC4043