A8181 Buck LED driver IC overview
Description
A8181 is a non-sync DC/DC Buck LED driver IC from . Maximum input voltage is 36.0 V and it drives an output current of up to 1.20 A. Assuming a typical 3.5V LED forward voltage A8181 can drive up to 7 LED in series.
The LED Buck driver IC features fixed 1000 kHz switching frequency, a feedback voltage of 0.10 V and requires a typical inductor size of 47.0 uH. This combination results in a peak efficiency of ~97 %. A8181 comes in 1 package option(s) - SOT89-5 .
Parameter and feature overview
Parameter | Value | Replacement Search Filter |
Nr. of Channel | 1 | |
V-IN min. | 6.0 V | |
V-IN max. | 36.0 V | |
Nr.of LEDs max. | 7 | |
I-OUT? | 1.20 A | |
MOSFET | intern | |
ext.clock sync. | ![]() |
|
sync/non-sync | non-sync | |
Frequency typ. | 1000 kHz | |
Frequency adjustable | fixed | |
Frequency min. | ||
Frequency max. | ||
Softstart | ![]() |
|
Softstart adjustable | ![]() |
|
Quiescent current max. | 50000 uA | |
Operating min. | -40 °C | |
Operating max. | 125 °C | |
Junction min. | ||
Junction max. | 150 °C | |
thermal shutdown typ. | 160.0 °C | |
Inductor size | 47.0 uH | |
Inductor suggested by Würth Elektronik | inductive | |
Feedback Voltage | 0.10 V | |
Automotive AEC-Q100 | ![]() |
|
Topology | Buck | |
Peak Efficiency | 97 % | |
Component count min. | 4 | |
DC Dimming | ![]() |
|
PWM Dimming | ![]() |
|
digital dimming | ![]() |
|
Nr. of package options | 1 | |
SC70 | ||
SOT | SOT89-5 | |
MSOP | ||
QFN/DFN | ||
SO/SOIC | ||
SOP | ||
DIP | ||
TO | ||
Variation | ||
LED temperature compensation |
A8181 Datasheet
Link to the most up-to-date A8181 datasheet and the product page for EVM, tools and support information.
A8181 inventory, samples and price


Available Distributors with stock: 0
Available Distributors with stock: 0
Equivalents and alternatives
The following DC/DC LED Buck driver are similar to A8181. Optional, compare A8181 side-by-side with other LED driver via the Comparison function.
Inductor suggestions
Below you can find matching inductors from Wuerth Elektronik calculated on the maximum parameters of A8181.
Order Code | Spec | L (µH) | IR (A) | ISAT (A) | RDC (mΩ) | L x W x H (mm) |
74404042100 | 10.0 | 1.2 | 1.5 | 150.00 | 4 x 4 x 1.8 | |
74404052100 | 10.0 | 1.6 | 2.0 | 109.00 | 5 x 5 x 2 | |
74404054100 | 10.0 | 2.1 | 2.5 | 64.00 | 5 x 5 x 4 | |
74404063082 | 8.2 | 2.3 | 2.5 | 55.00 | 6 x 6 x 2.8 | |
74404063100 | 10.0 | 2.0 | 2.2 | 72.00 | 6 x 6 x 2.8 | |
74404064120 | 12.0 | 2.2 | 3.0 | 58.00 | 6 x 6 x 4.5 | |
744053008 | 8.2 | 2.1 | 1.6 | 50.00 | 5.8 x 5.8 x 3 | |
7440650082 | 8.2 | 3.8 | 2.8 | 28.50 | 10 x 10 x 3.1 | |
744065100 | 10.0 | 3.0 | 2.5 | 40.00 | 10 x 10 x 3.1 | |
7440690082 | 8.2 | 1.7 | 1.5 | 99.00 | 8 x 8 x 1.5 | |
7440700082 | 8.2 | 2.2 | 1.7 | 70.50 | 8 x 8 x 2 | |
7440700100 | 10.0 | 2.0 | 1.6 | 78.00 | 8 x 8 x 2 | |
744071100 | 10.0 | 3.4 | 2.8 | 28.00 | 8 x 8 x 4.6 | |
74408942082 | 8.2 | 1.4 | 2.2 | 113.00 | 4.8 x 4.8 x 3 | |
74408942100 | 10.0 | 1.4 | 2.1 | 125.00 | 4.8 x 4.8 x 3 | |
74408943082 | 8.2 | 1.8 | 2.2 | 70.00 | 4.8 x 4.8 x 4.1 | |
74408943100 | 10.0 | 1.7 | 2.1 | 82.00 | 4.8 x 4.8 x 4.1 | |
74437321082 | 8.2 | 1.2 | 2.1 | 313.00 | 4.45 x 4.06 x 1.2 | |
74437324082 | 8.2 | 1.6 | 2.8 | 158.00 | 4.45 x 4.06 x 2 | |
74437324100 | 10.0 | 1.5 | 2.4 | 215.00 | 4.45 x 4.06 x 2 | |
74438336100 | 10.0 | 1.2 | 2.4 | 280.00 | 3 x 3 x 2 | |
7447462100 | 10.0 | 2.5 | 2.6 | 55.00 | 5.5 x 5.5 x 8.5 | |
744773082 | 8.2 | 1.5 | 1.8 | 116.00 | 4 x 4.5 x 3.48 | |
74477310 | 10.0 | 1.5 | 1.7 | 118.00 | 4 x 4.5 x 3.48 | |
744773112 | 12.0 | 1.3 | 1.6 | 156.00 | 4 x 4.5 x 3.48 | |
74477510 | 10.0 | 2.3 | 3.0 | 40.00 | 7 x 7.8 x 5.45 | |
744775112 | 12.0 | 2.2 | 2.2 | 41.70 | 7 x 7.8 x 5.45 | |
74477710 | 10.0 | 2.0 | 2.6 | 45.00 | 7.3 x 7.3 x 4.5 | |
744777112 | 12.0 | 1.8 | 2.4 | 54.00 | 7.3 x 7.3 x 4.5 | |
7447779008 | 8.2 | 2.7 | 3.0 | 47.00 | 7.3 x 7.3 x 4.5 | |
744777910 | 10.0 | 2.0 | 2.6 | 45.00 | 7.3 x 7.3 x 4.5 | |
7447779112 | 12.0 | 1.8 | 2.4 | 50.00 | 7.3 x 7.3 x 4.5 | |
74477810 | 10.0 | 1.8 | 2.2 | 68.00 | 7.3 x 7.3 x 3.4 | |
744778112 | 12.0 | 1.7 | 2.2 | 76.00 | 7.3 x 7.3 x 3.4 | |
744778510 | 10.0 | 1.9 | 1.6 | 100.00 | 5.9 x 6.2 x 3.3 | |
7447786008 | 8.2 | 2.3 | 2.1 | 66.00 | 5.9 x 6.2 x 5.1 | |
744778610 | 10.0 | 2.1 | 1.8 | 74.00 | 5.9 x 6.2 x 5.1 | |
744778910 | 10.0 | 1.8 | 2.2 | 64.00 | 7.3 x 7.3 x 3.5 | |
7447789112 | 12.0 | 1.7 | 1.9 | 76.00 | 7.3 x 7.3 x 3.5 | |
744779100 | 10.0 | 1.9 | 2.1 | 38.60 | 6 x 6 x 6.5 | |
744787082 | 8.2 | 2.7 | 2.8 | 33.00 | 7.8 x 7 x 5 | |
744787100 | 10.0 | 2.6 | 2.6 | 36.50 | 7.8 x 7 x 5 | |
744787120 | 12.0 | 2.5 | 2.4 | 45.00 | 7.8 x 7 x 5 | |
78438336100 | 10.0 | 1.2 | 2.4 | 280.00 | 3 x 3 x 2 | |
784773082 | 8.2 | 1.5 | 1.8 | 116.00 | 4 x 4.5 x 3.5 | |
78477310 | 10.0 | 1.5 | 1.7 | 118.00 | 4 x 4.5 x 3.5 | |
784773112 | 12.0 | 1.3 | 1.6 | 156.00 | 4 x 4.5 x 3.5 | |
78477410 | 10.0 | 2.2 | 2.5 | 78.00 | 5.2 x 5.8 x 4.85 | |
784774112 | 12.0 | 2.0 | 1.9 | 82.00 | 5.2 x 5.8 x 4.85 | |
78477510 | 10.0 | 2.3 | 3.0 | 40.00 | 7 x 7.8 x 5.5 | |
784775112 | 12.0 | 2.2 | 2.2 | 42.00 | 7 x 7.8 x 5.5 | |
784777082 | 8.2 | 2.0 | 2.8 | 97.50 | 7.3 x 7.3 x 4.3 | |
784777100 | 10.0 | 1.9 | 2.6 | 105.00 | 7.3 x 7.3 x 4.3 | |
784778082 | 8.2 | 2.2 | 2.4 | 86.00 | 7.3 x 7.3 x 3.5 | |
784778100 | 10.0 | 1.9 | 2.2 | 105.00 | 7.3 x 7.3 x 3.5 | |
784787082 | 8.2 | 2.7 | 2.8 | 33.00 | 7.8 x 7 x 5 | |
784787100 | 10.0 | 2.6 | 2.6 | 36.50 | 7.8 x 7 x 5 | |
784787120 | 12.0 | 2.5 | 2.4 | 45.00 | 7.8 x 7 x 5 |