AL8808WT-7 Diodes Inc., AL8808WT-7 Datasheet - Page 11

• Manufacturer Part Number: AL8808WT-7
• Description: LED Lighting Drivers LED MV Int Switch TS Switch TSOT25 T&R 3K
• Manufacturer: Diodes Inc.

Specifications of AL8808WT-7

• Rohs: yes
• Input Voltage: 6 V to 30 V
• Operating Frequency: 1 MHz
• Maximum Supply Current: 450 uA
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• Package / Case: TSOT-25
• Minimum Operating Temperature: - 40 C

Applicatio
PWM Dimmin
The CTRL pin is
output stage.
The ultimate PW
lower switching
the accuracy/line
At the start of e
threshold isn’t re
Greater PWM d
frequency.
The three figure
from a 12V rail a
As can be obse
value.
AL8808
Document number
Figure 36. 0
Figure 38. 0
on Informat
ng
WM dimming reso
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at +25°C for a no
s designed to be
r: DS35648 Rev. 2
earity of the PWM
each PWM cycle
frequencies and
s below show 0.
.2% PWM Duty
.2% PWM Duty
rved from Figure
(cont.)
68µH
22µH
e driven by both
ominal LED curre
e 37 greater dim
tion
olution is determ
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H Inductance
H Inductance
e the LED curre
/or higher PWM
accuracy will be
c ranges can be
2% duty cycle P
Cycle at 100Hz
Cycle at 500Hz
- 2
(cont.)
mming accuracy c
PWM pulse resol
ent of 670mA
ent needs to res
e achieved by r
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greatly affected.
PWM Frequenc
PWM Frequenc
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.
reducing the PW
can be achieved
w
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WM dimming fre
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that can be achie
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th the PWM dim
WM Duty Cycle
22µH Indu
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uctance
an open drain ou
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utput or push pu
PWM on-time. A
mV/R
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Frequency and
and the inducto
AL8808
January 201
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