YB1315 Datasheet, PDF (9/10 Pages) YOBON TECHNOLOGIES,INC. – High Efficiency Charge Pump White LED Driver

Preliminary YB1315
High Efficiency Charge Pump White LED Driver
η = ^POUT = ^{VOUT × IOUT} ×100%
P_IN
V_IN × I _IN
I_IN = I_OUT + I_Q
η = ^POUT =
V_OUT × I_OUT
×100%
P_IN V_IN × (I_OUT × Mode + I_Q )
Mode = 1.5
And then LEDs efficiency is defined as LED
forward voltage produces output current
divided by input power:
η = ^POUT =
V_F × I_OUT
×100%
P_IN V_IN × (I_OUT × Mode + I_Q )
Capacitor Selection
Ceramic capacitors such as X5R or X7R
are recommended to be used with the
YB1315. For the two flying capacitors C1
and C2, it is important to use low ESR
capacitors to avoid unnecessary efficiency
losses. Low ESR capacitors on VOUT
reduce the ripple voltage on the supply of
the current sources. Table 5 lists capacitor
types that have been tested with the
YB1315.
Table 5. Recommended Capacitors and WLED
Part
Value Voltage
C1608X5R1A105KT000E 1μF
10V
C1608X7R1A105KT0S0N 1μF
10V
C2012X7R1C225KT000N 2.2μF
16V
Manufacturer
TDK
ECJ1VB1A105K
ECJ2FB1A105K
ECJ2FB1A225K
LTW-193TS5
1μF
10V
1μF
10V
2.2μF
16V
－
－
Panasonic
Lite-On
Size
Website
0603
0805
0805
www.component.tdk.com
0603
0805
0805
－
www.panasonic.com
www.liteon.com.tw
YB1315 Rev.0.1
www.yobon.com.tw
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