A High Efficiency, 10 W, Dual Output - Universal Input Power Supply (Innoswitch3-Ep) - Power integrations InnoSwitch3 Application Note

Application Note
R3
2 MΩ
1%
BR1
DF08S
800 V
R4
1.8 MΩ
1%
C2 C3
F1
10 µF 10 µF
1 A
400 V 400 V
RT1
t
O
10 Ω
D7
90 - 265
DFLR1200-7
VAC
L N
L1
22 µF
330 µH
50 V
Figure 27. Schematic DER-611, 5 V, 0.3 A and 12 V, 0.7 A for HVAC (Heating, Ventilation and Air-Conditioning) Application.
A High Efficiency, 10 W, Dual Output – Universal Input Power
Supply (InnoSwitch3-EP)
The circuit in Figure 27 delivers 10 W output power from 90 VAC to
265 VAC input. Higher than 84% efficiency at 90 VAC input at full
load is achieved (using INN3672C from the InnoSwitch3-EP family), and
provides accurate cross regulation between two outputs with two SR
FETs.
Primary-side overvoltage protection is obtained using Zener diode
VR1. In the event of overvoltage occurred on any output, the
increased voltage at the output of the bias winding causes the Zener
diode VR1 to conduct and triggers the OVP latch in the primary-side
controller of the InnoSwitch3-EP IC.
34
Rev. A 10/18
C4
R8
1000 pF
200 kΩ
630 V
D1
R22
DFLR1600-7
68 Ω 600 V
4
3
VR1
MMSZ5231B-7-F
D V
D3
BAV21WS-7-F
CONTROL
R26
36 Ω
R6
1/10 W
6.2 kΩ
1/10 W
S
BPP
C5 C6
4.7 µF
16 V
C10
470 pF
250 VAC
2 FL1
C21 R25
1 nF 30 Ω
C19
200 V 1/8 W
680 µF
16 V
1 FL2
Q2
AO4486
6
R24 C22
62 Ω 1 nF
C18
1/8 W 200 V
560 µF
6.3 V
5
NC Q1
AO6420
T1
EE1621
R9
47 Ω
1/10 W
C7
2.2 µF
C8
25 V
330 pF
50 V
FB
IS
InnoSwitch3-EP
U1
INN3672C-H602
Output rectification of the 5 V output is provided by SR FET Q1, and
output rectification of the 12 V output is provided by SR FET Q2. The
timing of Q1 and Q2 turn-on is controlled by the 5 V winding voltage
sensed via R9 and the FORWARD pin of the IC. Resistor R16, R27
and R13 form a voltage divider network that senses the output
voltage from both outputs to provide better cross-regulation. The
feedback current ratio between 12 V and 5 V outputs is 1:3 to provide
better regulation on the 5 V output and good cross regulation.
Feedback compensation networks comprising capacitors C23 and C24
reduce output ripple voltage. Capacitor C8 provides decoupling to
prevent high frequency noise interfering with power supply operation.
Zener diode VR2 improves the cross regulation when the 5 V output
only is fully loaded when no-load is present on the 12 V output.
VR2
SMAZ8V2-13-F
8.2 V
L2
10 µH
R30
R27
100 Ω
1.2 MΩ
1/10 W
1%
C24
1/16 W
2.2 nF
50 V
L3
R29
10 µH
100 Ω R16
133 kΩ
1/10 W
1%
C23
1/16 W
2.2 nF
50 V
R13
33.2 kΩ
1%
1/16 W
R12
0.2 Ω
1%
AN-72
12 V, 0.7 A
C14
2.2 µF
25 V
5 V, 0.3 A
C12
2.2 µF
25 V
RTN
PI-8374-082018
www.power.com