NCP3163 データシートの表示（PDF） - ON Semiconductor
部品番号
コンポーネント説明
メーカー
NCP3163 Datasheet PDF : 20 Pages
| |||
NCP3163, NCV3163
Calculation
(See Notes 1,2,3)
ton
toff
Step−Down
Vout ) VF
Vin * Vsat * Vout
ton
toff
ton
ǒ Ǔ ƒ
ton
toff
)
1
CT
32.143
·
f
10*6
*
20
@
10*12
IL(avg)
Iout
Ipk (Switch)
RSC
L
Vripple(pp)
Vout
IL(avg)
)
DIL
2
0.25
Ipk (Switch)
ǒ Ǔ Vin * Vsat * Vout
DIL
ton
ǒ Ǔ2
DIL
1
8 ƒ CO
) (ESR)2
ǒ Ǔ Vref
R2
R1
)
1
Step−Up
Vout ) VF Vin
Vin Vsat
ton
toff
ǒ Ǔ ƒ
ton
toff
)
1
32.143
·
f
10*6
*
20
@
10*12
ǒ Ǔ Iout
ton
toff
)
1
IL(avg)
)
DIL
2
0.25
Ipk (Switch)
ǒ Ǔ Vin * Vsat
DIL
ton
[
ton Iout
CO
ǒ Ǔ Vref
R2
R1
)
1
Voltage−Inverting
|Vout| ) VF
Vin * Vsat
ton
toff
ǒ Ǔ ƒ
ton
toff
)
1
32.143
·
f
10*6
*
20
@
10*12
ǒ Ǔ Iout
ton
toff
)
1
IL(avg)
)
DIL
2
0.25
Ipk (Switch)
ǒ Ǔ Vin * Vsat
DIL
ton
[
ton Iout
CO
ǒ Ǔ Vref
R2
R1
)
1
The following Converter Characteristics must be chosen:
Vin − Nominal operating input voltage.
Vout − Desired output voltage.
Iout − Desired output current.
DIL − Desired peak−to−peak inductor ripple current. For maximum output current it is suggested that DIL be chosen to be less
than 10% of the average inductor current IL(avg). This will help prevent Ipk (Switch) from reaching the current limit
threshold set by RSC. If the design goal is to use a minimum inductance value, let DIL = 2(IL(avg)). This will
proportionally reduce converter output current capability.
p − Maximum output switch frequency.
Vripple(pp) − Desired peak−to−peak output ripple voltage. For best performance the ripple voltage should be kept to a low value
since it will directly affect line and load regulation. Capacitor CO should be a low equivalent series resistance (ESR)
electrolytic designed for switching regulator applications.
NOTES: 1. Vsat − Saturation voltage of the output switch, refer to Figures 10 and 11.
NOTES: 2. VF − Output rectifier forward voltage drop. Typical value for 1N5822 Schottky barrier rectifier is 0.5 V.
NOTES: 3. The calculated ton/toff must not exceed the minimum guaranteed oscillator charge to discharge ratio of 8, at the minimum
NOTES: 3. operating input voltage.
Figure 22. Design Equations
http://onsemi.com
11
Share Link: 