ncp5050 ON Semiconductor, ncp5050 Datasheet - Page 6

• Manufacturer Part Number: ncp5050
• Description: 4.5 W Inductive Boost Led Driver For Flash And Lcd Backlight
• Manufacturer: ON Semiconductor

13. Pulse of 500 ms every 3 s in Flash Mode (Current following through HCS pin).
14. Efficiency = 100 x (Number of LED stacked x V
1000
800
600
400
200
90
80
70
60
50
90
80
70
60
50
0
10
10
5
L = TDK VLF5014A-2R7M1R5, (Notes 13 and 14)
Figure 4. Maximum Output Current Available
L = TDK VLF5014A-2R7M1R5, (Notes 13 and 14)
V
Operating Area
in
Figure 6. Efficiency vs. Current @ 2 LEDs
= 3.3 V
Figure 8. Efficiency vs. Current @ 4 LEDs
V
10
in
V
in
= 4.2 V
V
V
= 3.7 V
V
in
in
(7.0 V @ 350 mA),
in
V
V
= 4.2 V
= 5.0 V
(14 V @ 350 mA),
in
in
= 5.0 V
= 4.2 V
= 3.7 V
vs. V
I
I
V
out
out
V
out
in
15
100
100
(mA)
(mA)
= 3.8 V
(V)
out
V
TYPICAL OPERATING CHARACTERISTICS
in
V
= 3.3 V
in
= 3.3 V
LED
20
x I
LED
http://onsemi.com
)/P
NCP5050
in
.
1000
1000
25
6
1200
1000
800
600
400
200
90
80
70
60
50
90
80
70
60
50
0
2.5
L = TDK VLF5014A-2R7M1R5, (Notes 13 and 14)
10
10
L = TDK VLF5014A-2R7M1R5 (Notes 13 and 14)
Figure 5. Typical Maximum Output Current vs.
Input Voltage, L = TDK VLF5014A-2R7M1R5
Figure 7. Efficiency vs. Current @ 3 LEDs
Figure 9. Efficiency vs. Current @ 5 LEDs
3.0
V
in
V
= 3.7 V
(10.5 V @ 350 mA),
in
(17.5 V @ 350 mA),
3.5
V
= 4.2 V
2 LEDs
V
in
V
V
in
in
= 3.7 V
in
3 LEDs
= 5.0 V
(Note 13)
= 4.2 V
= 5.0 V
V
I
out
in
4.0
100
100
4 LEDs
V
(V)
5 LEDs
(mA)
in
V
= 3.3 V
in
= 3.3 V
4.5
5.0
1000
1000
5.5