NCP3066SCBCKGEVB ON Semiconductor, NCP3066SCBCKGEVB Datasheet - Page 9

• Manufacturer Part Number: NCP3066SCBCKGEVB
• Description: EVAL BOARD FOR NCP3066SCBCKG
• Manufacturer: ON Semiconductor

Specifications of NCP3066SCBCKGEVB

• Design Resources: NCP3066 Buck SOIC EVB BOM NCP3066SCBCKGEVB Gerber Files NCP3066 BUCK EVB Schematic
• Current - Output / Channel: 150mA
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 3.2V
• Features: Brightness Control
• Voltage - Input: 12V
• Utilized Ic / Part: NCP3066
• Silicon Manufacturer: On Semiconductor
• Silicon Core Number: NCP3066
• Kit Application Type: Power Management - Voltage Regulator
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: NCP3066SCBCKG
• Other names: NCP3066SCBCKGEVBOS

of the NCP3066. Two main converter topologies are
demonstrated with actual test data shown below each of the
circuit diagrams. The demo boards have an input for a digital
dimming signal. You can provide a PWM signal to change
9. V
10. V
11. The calculated t
The Following Converter Characteristics Must Be Chosen:
less than 10% of the average inductor current I
set by R
converter output current capability.
value since it will directly affect line and load regulation. Capacitor C
electrolytic designed for switching regulator applications.
Figures 15 through 24 show the simplicity and flexibility
V
V
I
DI
f − Maximum output switch frequency.
V
out
out
in
ripple(pp)
SWCE
F
L
Parameter
I
− Output rectifier forward voltage drop. Typical value for 1N5819 Schottky barrier rectifier is 0.4 V.
V
− Nominal operating input voltage.
pk (Switch)
− Desired output current.
− Desired peak−to−peak inductor ripple current. For maximum output current it is suggested that DI
− Desired output voltage.
ripple(pp)
I
L(avg)
R
SC
t on
t off
I
t
C
out
on
− Darlington Switch Collector to Emitter Voltage Drop, refer to Figures 7 and 8.
L
SC
T
. If the design goal is to use a minimum inductance value, let DI
− Desired peak−to−peak output ripple voltage. For best performance the ripple voltage should be kept to a low
on
/t
off
must not exceed the minimum guaranteed oscillator charge to discharge ratio.
V in * V SWCE * V out
DI L
V in * V SWCE * V out
L(avg)
Figure 14. Design Equations
V
I L(avg) )
R
f
I pk (Switch)
Step−Down
V out ) V F
ref
. This will help prevent I
DI L
8 f C O
s
http://onsemi.com
APPLICATIONS
1
0.20
I out
t on
t off
t on
t off
C T + 381.6 @ 10
) 1
2
DI L
) (ESR)
2
9
the average output current and reduce the LED brightness.
Figure 14 gives the relevant design equations for the key
parameters. Additionally, a complete application design aid
for the NCP3066 can be found at www.onsemi.com.
f osc
t on
2
O
*6
should be a low equivalent series resistance (ESR)
pk (Switch)
* 343
L
= 2(I
from reaching the current limit threshold
L(avg)
10
*12
). This will proportionally reduce
t on I out
C O
V in * V SWCE
V out ) V F * V in
V in * V SWCE
I out
I L(avg) )
I pk (Switch)
f
Step−Up
) DI L
DI L
V
R
0.20
ref
s
L
t on
t off
t on
t off
t on
t off
be chosen to be
) 1
DI L
2
) 1
ESR
t on