Evaluation and Finding of Isolated Flyback Converter: © 2016 ROHM Co.,Ltd
Evaluation and Finding of Isolated Flyback Converter: © 2016 ROHM Co.,Ltd
Evaluation and Finding of Isolated Flyback Converter: © 2016 ROHM Co.,Ltd
AGENDA
Description: BM2P014
• Easy to design various types of low power
AC/DC converter with integrated 650V
MOSFET, and configurable to both isolated
and non-isolated
• High flexibility in design with external
current sense resistor and current mode
provides cycle by cycle current limiting
and high speed load transient response.
• Low power with internal 650V start-up
circuit and high efficiency at right load
with switching frequency reduction
function
Product lineup
Part # MOSFER Ron
Circuit Example
F1
1.6A/
ACIN_L AC250V LF1
BR1
D6
800V 1A
FRD 200V 5A Vout
AC90V ZNR1 1
T1
8,9
-264V
C1 R4 C2
47uF 120k 2200pF C12 C15 12V
400V 1000uF 0.1uF
ACIN_N
C3 D3 25V 16V 1.5A
0.1uF/X2 FRD
650V 0.5A
C8 3 6,7
100pF D4 R5 GND
1kV 200V 0.5A 5.1 4
C5
10uF
8
5
50V R11 R12
Drain
Drain
VCC
2k 43k
IC1
BM2P014
R13
Source
5 R6 2.7k
GND
NC
1.2k
FB
C7
1
2200pF/Y1 C10 R7
0.1uF 1k
4 1
C6 PC1 IC2 R8
R3 1000pF PC817 TL431 12k
0.39 3 2
NP2
3 10
NP1 NS1 ND NS2 NP2
NS2
4 9
ND NS1
5 8 4mm
6 7 Insulation tape 3T
Tolerance P-S : AC3.0KVrms 1MIN. 2mA or AC3.6KVrms 1S 2mA Beginning of winding: Fixed with barrier tape
PS-CORE : AC1.5KVrms 1MIN. 2mA or AC1.8KVrms 1S 2mA End of winding:Drawn to form a right angle & held in
IR : P-S,PS-CORE 100MΩ MIN. at DC 500V Winding direction: Uniformed
45mm
90mm
Measurement Methods
Parameters Conditions Equipment
Input Voltage Input 90VAC, 100VAC, 230VAC and 264VAC Voltage meter (AC), Power
using a high voltage step-up/step-down meter
transformer.
Input Current Measure at each Vin with all Iout range Clamp ammeter, Power
meter
Input Voltage Measure Vin Voltage meter (AC), Power
meter, Clamp ammeter
Output Voltage Measure at each Vin with full of Iout range Voltage meter (DC)
Output Current 0A to 1.5A using adjustable load equipment Ammeter (DC)
Isolated AC/DC
Converter 0A~1.2A
(+)
IDC
Vout
Load
90VAC~
Vin VDC 12Vout
AC
VAC
264VAC
(-)
Pout
W Efficiency (%) =
Pin
IAC
Vout
<Conditions to Verify>
Vin: Min and max
Load:Max
Environment:Max and min
Vds Vds
Ids Ids
<Conditions to Verify>
Vin: Min & max at start-up & ordinary state
Load current: Max
Ambient Temperature: Min and max
Ids
<Conditions to Verify>
Vin: Max and min
Load current: Max
Ambient Temperature: Min and max
Vr
BR1
D6
2.Finding of AC90V
Isolated Flyback Converter
800V 1A
T1 FRD 200V 5A
ZNR1 1 8,9
-264V
C1 R4 C2
120k 2200pF C12
④ Vcc pin voltage
47uF
400V 1000uF
C3 D3 25V
ACIN_N
0.1uF/X2 FRD
5
R11
• The surge voltage is induced by the Vcc
50V
Drain
Drain
VCC
IC1 2k
Source
5 R6
GND
NC
• R5 as limiting resistor can be used to reduce
1.2k
FB
C7
4
the surge voltage induced by the Vcc 2200pF/Y1 C10
0.1uF
windings 4 1
<Finding>
Vcc pin voltage > 9.7V at Vin = min & max, and load current = min (or no load)
Vcc pin voltage < 26V at Vin = min & max, and load current = max
R4 Min and
Vin: C2 max
120k 2200pF C12 C15 12V
Load: Max D3to min and min 1000uF
25V to max
0.1uF
16V 1.5A
Temperature: Min and max
FRD
Ambient 650V 0.5A Vout
3 6,7
D4 R5 GND
Vout fluctuation
200V 0.5A 5.1 4
C5
10uF
7
Drain
VCC
2k 43k
IC1
BM2P014
R13
Source
5 R6 2.7k
GND
NC
1.2k
FB
2200pF/Y1
need to adjust the gain
C10 R7
0.1uF 1k
4 1 and phase characteristics
C6 PC1 IC2 R8
R3 1000pF PC817 TL431 12k
0.39 3 2
<Conditions to verify>
Vin: Min and max
Load: Max and min Vout
Ambient Temperature: Min and max
Calcuration of Tj
Ex. BM2P014 θja
Tc
θjc
Tj
MOSFET CHIP Control CHIP
FLAME FLAME
DRAIN OTHER
θjc= (Tj-Tc)/P [℃/W]
Tj = Tc + P*θjc
②
②
④
Die Temperature
Calculation
Support Site
http://www.rohm.com/web/global/groups/-/group/groupname/Transistors Usability Judgment Method
C9
100m
22 33p
R4 TX1 R21
180
Set Ta
DRF08L6S R12 P1 S1
D5 2.7u
100m
R6 D2
L1
R8008ANX DRF601T2D
P2
C3 Vo24
10 D1 220p D4
R1 Q4 39k
C4 R108
100 15k DRF601T2D
R7 R8
150m 3k 100m 1.5m R2
R5 R107 R19 C1 6.67
2k
R13
Set θ
BD7681beta
U1 103.3k
OUT ZTin R16
VFB 1k
(V(drain)-V(source))*I(d) U6 R3
Vcs
ARB1 GND C2
1n IC=4
I(d)
OUT POWER
POWER
drain 10n
12k
source
R20
C5
Loss model
U7
12k
R18
Change Tj to
Calculate loss & Tj calculated value
Size
ヒートシン クサイ ズ 25*20 25*43 50*54
-------
|Ta-Tj| < 0.2℃ 熱抵抗 - 20℃/W 16℃/W 13℃/W
θ0 50 50 50
1 97.2 87.7 80.6
2 115.2 98.1 87.2
Cubic volume of 16℃/W
3 128.5 103.2 89.2
is 2.5 x of 13℃/W
4 154.7 104.9 89.6
5 323.7 106.2 89.8
Fix Tj and loss 6 106.9
7 106.7
・If the capacitor deteriorates, a leakage occurs and the capacitance lowers
⇒Affections for a power supply circuit:
REVIEW