APE1601 Advanced Power Electronics Corp., APE1601 Datasheet - Page 9

• Manufacturer Part Number: APE1601
• Manufacturer: Advanced Power Electronics Corp.

Specifications of APE1601

• Support Voltage (min.): 2.5V
• Support Voltage (max.): 5.5V
• Frequency: 1MHz
• Quiescent Current Typ.: 3mA
• Output Current: 120mA
• Efficiency: 90%
• Package: QFN 3x3-16L

White LED Driver (120mA Charge Pump with Current Source)
Advanced Power
Electronics Corp.
LED current setting with NMOS
LED current setting control can also be achieved by using the external NMOS to change
equivalent resister of ISET pin. Figure 3 shows this application circuit of method. For this
example, a 3 bit signals can set 8 kinds of different equivalent resister of ISET pin, i.e.
produce 8 kinds of LED current level. Table 3 shows the relation between equivalent
resister of ISET pin and control signal.
LED Dimming Control Methods
The APE1601/A can use two methods to achieve the LED dimming control. These methods
are detailed described as following:
Table 3. The relation between control signal and equivalent resister of I
Figure 3. The application circuit of setting LED current which
S1
0
0
0
0
1
1
1
1
S2
0
0
1
1
0
0
1
1
APE1601/A
GND
S3
uses a NMOS to set R
0
1
0
1
0
1
0
1
I
SET
R4
Equivalent Resister of I
R
SET
R
R
R
R1
R3
R2
SET
SET
SET
R
R
R
=R1//R2//R3//R4
SET
SET
SET
R
=R2//R3//R4
=R1//R3//R4
=R1//R2//R4
SET
SET
=R3//R4
=R2//R4
=R1//R4
.
=R4
S1
S3
S2
SET
pin(R
SET
APE1601/A
)
SET
pin
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