R1218K021A RICOH [RICOH electronics devices division], R1218K021A Datasheet - Page 11

• Manufacturer Part Number: R1218K021A
• Description: Step-up DC/DC converter for White LED Backlight
• Manufacturer: RICOH [RICOH electronics devices division]

4) Efficiency vs. LED Current (6LED) L: LQH32CN220, Diode: CRS02 (Topt=25°C)
5) PWM Dimming Control (2 LED) V
5-1. Duty vs. LED Current (Topt=25°C)
100
100
25.0
22.5
20.0
17.5
15.0
12.5
10.0
90
80
70
60
50
40
30
20
10
90
80
70
60
50
40
30
20
10
7.5
5.0
2.5
0
0
0
0
0
0
4
4
20
LED Current l
LED Current l
R1218x062A
R1218x062A
R1218x021A
8
8
40
Duty (%)
12
12
LED
LED
60
(mA)
(mA)
V
V
16
16
IN
IN
80
5kHz
1kHz
200Hz
IN
=2.7V
=4.2V
=3.6V, R1=10Ω
20
20
100
100
90
80
70
60
50
40
30
20
10
0
0
4
LED Current l
R1218x062A
8
12
LED
(mA)
V
16
IN
=3.6V
R1218x
20
11