ncp1653 ON Semiconductor, ncp1653 Datasheet - Page 17

• Manufacturer Part Number: ncp1653
• Description: Compact Fixed-frequency Current-mode Power Factor Correction Controller
• Manufacturer: ON Semiconductor

APPENDIX I – SUMMARY OF EQUATIONS IN NCP1653 BOOST PFC
Boost Converter
Input Current Averaged by
Filter Capacitor
Nominal Output Voltage (I
= 200 mA)
Feedback Pin Voltage V
Output Voltage
Inductor Current
Peak−Peak Ripple
Control Current
Switching Frequency
Minimum Inductor for CCM
Input Impedance
Input Power
Output Power
Maximum Input Power when
I
Current Limit
Power Limit
Output Overvoltage
Output Undervoltage
Input Voltage Sense Pin
Resistor R
PWM Comparator
Reference Voltage
control
= 100 mA
Description
vac
FB1
FB
³
Please refer to Figure 11.
V out
V in t V out t 192 mA @ R FB
DI L(pk * pk) t 2 @ I L * 50
P in +
I in + I L * 50
V in
V out(nom) + I FB R FB ) V FB1
I control + I control(max) +
f + 67 or 100 kHz
L u L (CRM) +
Z in +
P out + hP in +
P in(max) + P in +
I L(OCP) +
I L @ V AC t
V out(OVP) + 107% @ V out(nom)
V out(UVP * on) + 8% @ V out(nom)
V out(UVP * off) + 12% @ V out(nom)
R vac u 938 kW and R vac +
V ref + 2.62 V
V out * V in
+
R S R vac I ref V ref
R M R CS V ac V out
R S R vac I ref V ref
t 1 ) t 2
V out
t 2
R M R CS
[ I FB R FB + 200 mA @ R FB
R CS
[ 214 mA @ R FB
R CS
Follower Boost Mode
R S
R S
+
+
V out * V in
hR S R vac I ref V ref
@ 200 mA
[ 16 mA @ R FB
[ 24 mA @ R FB
R vac ) 12 kW
T * t 1
t 1 ) t 2
NCP1653, NCP1653A
R S R vac I ref V ref
V out
T
t 1
R M R CS
http://onsemi.com
R M R CS
V out
2
V ac
+
I ref
DI L(pk * pk)
2
t 1
T
R vac ) 12 kW
+ 100 mA
17
@ 3 nA 2
V in
V out
V ac
V out
2
V ac
1
f
192 mA @ R FB t V out t 200 mA @ R FB
Same as Follower Boost Mode
Same as Follower Boost Mode
Same as Follower Boost Mode
Same as Follower Boost Mode
Same as Follower Boost Mode
Same as Follower Boost Mode
Same as Follower Boost Mode
Circuit will enter follower boost region when
maximum power is reached.
Same as Follower Boost Mode
Same as Follower Boost Mode
Same as Follower Boost Mode
Same as Follower Boost Mode
Same as Follower Boost Mode
Same as Follower Boost Mode
I control +
and I control t I control(max) + 100 mA
Z in +
P in +
P out +
2R S R vac I control V ref
2R S R vac V ref
Constant Output Voltage Mode
h2 R S R vac V ref
R M R CS V ac V out
R M R CS
I control(max)
R M R CS
0.04
I control V ac
1 *
V out
I control V ac
V out
R FB I ref
V out