- 您現(xiàn)在的位置：買(mǎi)賣(mài)IC網(wǎng) > PDF目錄364677 > AN-30 TOPSwitch-GX Forward Design Methodology PDF資料下載
參數(shù)資料
| 型號(hào)： | AN-30 |
| 英文描述： | TOPSwitch-GX Forward Design Methodology |
| 中文描述： | 的TOPSwitch - GX系列正向設(shè)計(jì)方法 |
| 文件頁(yè)數(shù)： | 15/40頁(yè) |
| 文件大?。?/td> | 311K |
| 代理商： | AN-30 |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)當(dāng)前第15頁(yè)第16頁(yè)第17頁(yè)第18頁(yè)第19頁(yè)第20頁(yè)第21頁(yè)第22頁(yè)第23頁(yè)第24頁(yè)第25頁(yè)第26頁(yè)第27頁(yè)第28頁(yè)第29頁(yè)第30頁(yè)第31頁(yè)第32頁(yè)第33頁(yè)第34頁(yè)第35頁(yè)第36頁(yè)第37頁(yè)第38頁(yè)第39頁(yè)第40頁(yè)
AN-30
15
B
12/02
voltage, and the voltage on the L pin as shown in Figure 1. The
Zener diode is chosen as required to raise the curve of D
at
the low input voltages. It may not be necessary in all applications.
The Zener voltage is 6.8 V in this example.
Next, select a value for D
XHL
that is between D
HL_ACTUAL
and
D
HL_RESET
.
(40)
(41)
Find the range of permissible values for D
.
To compute the
upper and lower bounds on D
XDO
, define the intermediate
variable K
XDO.
(42)
The upper bound for D
XDO
is then
(43)
and the lower bound for D
XDO
is
(44)
Choose an appropriate value for D
between D
and
D
MAX_ACTUAL
that also satisfies the boundaries of (43) and (44).
Next, compute the intermediate constants r
1
and r
2
.
(45)
While there are four resistors, only three are unknown because
R
and R
are identical by definition. They are connected in
series to keep the voltage across each one below its maximum
rating. The three unknown resistors and one capacitor make
four unknown quantities that are determined by the four
constraints.
Figure 8 illustrates the general case where D
is between the
actual duty ratio D
and D
at the input voltage
V
. If the converter is not required to respond to transient
loads at the end of the holdup time, D
and D
can
be set to D
. Since response to transient loads is usually
required at V
, the designer will want to set D
XHL
at a
comfortable margin between D
HL_ACTUAL
and D
HL_RESET
Begin with the computation of values for R
A
and R
B
to set the
line under-voltage threshold V
ACUV
.
(35)
where V
is the AC input voltage (non-doubled) required for
the converter to start, and I
is the line under-voltage threshold
current of the L pin of
TOPSwitch-GX
from the datasheet.
Choose the nearest standard resistor value for R
A
and R
B
.
Define intermediate variables to make the expressions easier to
write and interpret.
D
I
L
(36)
(37)
(38)
(39)
In Equation (36), D
IL1
and D
are respectively the values of
DC
at currents I
and I
into the L pin. Obtain these values
from the data sheet. Use the typical values at first. Then check
that the circuit will perform properly at the high and low ends
of the tolerance range.
In Equation (37), D
is the value of DC
at current I
L
into the
L pin. Use the same D
with I
or D
with I
L2
as in
Equation (36). Either pair will give the same result. I
has a
physical interpretation that cannot be realized: if the duty ratio
reduction characteristic continued along its linear slope, it
would reach zero at the current I
LD0
.
The voltages V
, V
and V
are respectively the forward drop
of the rectifier in series with the Zener diode and R
C
, the Zener
R
R
V
I
A
B
ACUV
2
UV
=
=
2
R
R
R
AB
A
B
≡
+
I
D
m
I
LD
IL
IL
L
0
≡
+
V
V
V
V
BZL
DB
Z
L
≡
+
+
D
V
V
V
V
N
N
V
V
HL
ACTUAL
MAIN
)
DMAINC
MAX
DS
S
P
DMAINF
DMAINC
_
=
+
(
+
D
V
V
HL
RESET
MAX
DSOP
_
=
1
K
m
I
V
R
D
m
V
N
N
V
V
N
N
V
XDO
IL
LD
MAX
AB
XHL
IL
DROPOUT
B
P
BZL
MAX
B
P
BZL
≡
0
D
m
I
V
R
K
XDO
IL
LD
DROPOUT
AB
XDO
<
0
D
m
I
V
R
K
D
XDO
IL
LD
DROPOUT
AB
XDO
XHL
>
+
0
1
m
D
I
IL
IL
IL
L
≡
1
2
2
1
r
V
N
N
V
D
I
V
R
D
m
DROPOUT
B
P
BZL
XDO
LD
DROPOUT
AB
XDO
IL
1
0
≡
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| AN-31 | DPA-Switch Forward Converter Design Guide |
| AN-32 | TOPSwitch-GX Flyback Design Methodology |
| AN-37 | LinkSwitch-TN Design Guide |
| AN-995A | Electronic Ballasts Using the Cost-Saving IR215X Drivers(153.99 k) |
| AN0416NA | TRANSISTOR | MOSFET | ARRAY | N-CHANNEL | 160V V(BR)DSS | 30MA I(D) | DIP |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| AN300 | 功能描述:環(huán)境檢測(cè)設(shè)備 Large Vane CFM/CMM Thermo-Anemometer RoHS:否 制造商:Fluke 設(shè)備類(lèi)型:Vibration Meter 測(cè)量?jī)x器:Vibration |
| AN3000-521P | 制造商:未知廠(chǎng)家 制造商全稱(chēng):未知廠(chǎng)家 功能描述:AN0625-521P |
| AN3001 | 制造商:MA-COM 制造商全稱(chēng):M/A-COM Technology Solutions, Inc. 功能描述:PIN diode Vector Modulators - Fundamentals and Drive Requirements |
| AN-3001 | 制造商:FAIRCHILD 制造商全稱(chēng):Fairchild Semiconductor 功能描述:Application Note AN-3001 Optocoupler Input Drive Circuits |
| AN-3002 | 制造商:FAIRCHILD 制造商全稱(chēng):Fairchild Semiconductor 功能描述:Low Current Input Circuit Ideas |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。