S-8813 Datasheet, PDF (22/29 Pages) Seiko Instruments Inc – 3-CHANNEL WHITE LED DRIVER IC (CHARGE PUMP IC WITH BUILT-IN CONSTANT-CURRENT CIRCUIT)

3-CHANNEL WHITE LED DRIVER IC (CHARGE PUMP IC WITH BUILT-IN CONSTANT-CURRENT CIRCUIT)
S-8813 Series
Rev.2.1_00
9. Maximum Oscillation Frequency (f_OSC) vs. Operation Input
Voltage (V_IN) Characteristics
800
750
700 _Ta=85°C
650
600 _Ta=25°C
550
500
450 Ta=−40°C
400
2.0 2.5 3.0 3.5 4.0 4.5 5.0
VIN [V]
11. Stabilized Output Current (I_OUT) vs. Operation Input Voltage
(V_IN) Characteristics
R1=5.6 kΩ, Ta=25°C
20
19
18
17
VIOUT=3.0 V
VIOUT=3.0 V
16
VIOUT=4.0 V
15
2.0 2.5 3.0 3.5 4.0 4.5 5.0
VIN [V]
13. Inter-Pin Output Current Variation (ΔI_M) vs. Operation Input
Voltage (V_IN) Characteristics
10. Soft Start Time (t_SS) vs. Operation Input Voltage (V_IN)
Characteristics
2.5
2.0
1.5 ^{From the top}
1.0 ^Ta=85°C
Ta=25°C
0.5 _{Ta=−40°C}
0.0
2.0 2.5 3.0 3.5 4.0 4.5 5.0
VIN [V]
12. Stabilized Output Current (I_OUT) vs. Operation Input Voltage
(V_IN) Characteristics
VISET=1.8 V, Ta=25°C
20
19
18
17
VIOUT=3.0 V
16
VOUT=3.5 V
VOUT=4.0 V
15
2.0 2.5 3.0 3.5 4.0 4.5 5.0
VIN [V]
1.0
0.8
0.6
0.4
Ta=85°C
Ta=25°C
0.2
Ta=−40°C
0.0
2.0 2.5 3.0 3.5 4.0 4.5 5.0
VIN [V]
*1. “Efficiency” in the electrical characteristics means the efficiency of the charge pump circuit block. The ideal efficiency is
indicated by the following expression.
Efficiency =[ V_CPOUT × (I_OUT1 +I_OUT2 +I_OUT3) ] / [ 2.0 × V_IN × (I_OUT1 +I_OUT2 +I_OUT3) ]
The ideal efficiency including the constant current circuit is expressed as following expression.
Efficiency =[ (V_IOUT1 ×I_OUT1) + (V_IOUT2 ×I_OUT2) + (V_IOUT3 ×I_OUT3) ] / [ 2.0 ×V_IN × (I_OUT1 +I_OUT2 +I_OUT3) ]
22
Seiko Instruments Inc.