Diodes AL8400, AL8400Q User Manual
Green
LINEAR LED DRIVER-CONTROLLER with 200mV
CURRENT SENSE VOLTAGE and AUTOMOTIVE GRADE
Description
The AL8400 is a 5-terminal adjustable Linear LED driver-controller
offering excellent temperature stability and output handling capability.
The AL8400 simplifies the design of linear and isolated LED drivers.
With its low 200mV current sense FB pin, it controls the regulation of
LED current with minimal power dissipation when compared to
traditional linear LED drivers. This makes it ideal for medium to high
current LED driving.
The AL8400 open-collector output can operate from 0.2V to 18V
enabling it to drive external MOSFET and Bipolar transistors. This
enables the MOSFET and Bipolar selection to be optimized for the
chosen application. It also provides the capability to drive longer LED
chains, by tapping V
from the chain, where the chain voltage may
CC
exceed 18V.
It is available in the space saving low profile SOT353 package.
The AL8400Q is Automotive Grade and is AEC-Q100 Grade 1
qualified.
Applications
• Isolated Offline LED Lamps
• Linear LED Driver
• LED Signs
• Instrumentation Illumination
Notes: 1. EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. All applicable RoHS exemptions applied.
2. See http://www.diodes.com for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green" and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
Pin Assignments
Features
• Low Reference Voltage (VFB = 0.2V)
• -40 to +125°C Temperature Range
• 3% Reference Voltage Tolerance at +25°C
• Low Temperature Drift
• 0.2V to 18V Open-Collector Output
• High Power Supply Rejection:
(> 45dB at 300kHz)
• AL8400QSE-7 Automotive Grade qualified to AEC-Q100 Grade 1
• SOT353: Available in “Green” Molding Compound (No Br, Sb)
Lead-Free Finish; RoHS Compliant (Notes 1 & 2)
Halogen and Antimony Free. “Green” Device (Note 3)
AL8400 /AL8400Q
Typical Applications Circuit
GND
AL8400/ AL8400Q
Document number: DS35115 Rev. 4 - 2
Vcc
R
3
Vcc
C
D
OUT
B
5
AL8400
Q2
4
FB
C
L
R
GND
I
= V
LED
E1
12
REF/RSET
1 of 13
www.diodes.com
SET
August 2012
© Diodes Incorporated
AL8400 /AL8400Q
Pin Descriptions
Pin
Number
1 E1 Emitter Connection. Connect to GND.
2 GND Analog Ground. Ground return for reference and amplifier. Connect to E1.
3 VCC Supply Input. Connect a 0.47F ceramic capacitor close to the device from VCC to GND.
4 FB Feedback Input. Regulates to 200mV nominal.
5 OUT Output. Connect a capacitor close to device between OUT and GND. See the Applications Information section.
Name Function
Functional Block Diagram
Absolute Maximum Ratings (@T
Symbol Parameter Rating Unit
VCC Supply Voltage Relative to GND 20 V
V
OUT Voltage Relative to GND 20 V
OUT
VFB FB Voltage Relative to GND 20 V
VE1 E1 Voltage Relative to GND -0.3 to+0.3 V
TJ Operating Junction Temperature -40 to 150 °C
TST Storage Temperature -55 to 150 °C
These are stress ratings only. Operation outside the absolute maximum ratings may cause device failure.
Operation at the absolute maximum rating for extended periods may reduce device reliability.
= +25°C, unless otherwise specified.)
A
Figure 1 Block Diagram
Package Thermal Data
P
Package θ
SOT353 400°C/W 310mW
AL8400/ AL8400Q
Document number: DS35115 Rev. 4 - 2
JA
T
= +25°C, TJ = +150°C
A
www.diodes.com
DIS
2 of 13
August 2012
© Diodes Incorporated
A
A
A
A
A
A
A
A
A
A
AL8400 /AL8400Q
Recommended Operating Conditions (@T
= +25°C, unless otherwise specified.)
A
Symbol Parameter Min Max Units
VCC Supply Voltage Range 2.2 18
V
OUT Voltage Range 0.2 18
OUT
I
OUT Pin Current 0.3 15 mA
OUT
V
TA Operating Ambient Temperature Range -40 +125 °C
Electrical Characteristics (Note 4) (@T
= +25°C, VCC= 12V, V
A
OUT
= VFB, I
= 1mA, unless otherwise specified.)
OUT
Symbol Parameter Conditions Min Typ Max Units
T
VFB Feedback Voltage
FB
Feedback Pin Load Regulation I
LOAD
FB
Feedback Pin Line Regulation V
LINE
FB
Output Voltage Regulation
OVR
= 1 to 15mA
OUT
= 2.2V to 18V
CC
V
= 0.2V to 18V, I
OUT
(Ref. Figure 1)
IFB FB Input Bias Current VCC = 18V
ICC Supply Current V
I
OUT Leakage Current V
OUT(LK)
Z
Dynamic Output Impedance I
OUT
= 2.2V to 18V, I
CC
= 18V, V
CC
= 1 to 15mA, f < 1kHz
OUT
PSRR Power Supply Rejection Ratio f = 300kHz, V
=1mA
OUT
=10mA
OUT
= 18V, VFB =0V
OUT
= 0.3VPP T
C
= +25°C 0.194 0.2 0.206
TA = -40°C to +125°C 0.190 0.210
= +25°C 3.1 6
T
TA = -40°C to +125°C 10
T
= +25°C 0.1 1.5
TA = -40°C to +125°C 2
= +25°C 2
T
TA = -40°C to +125°C 3
= +25°C -45
T
TA = -40°C to +125°C -200 0
T
= +25°C 0.48 1
TA = -40°C to +125°C 1.5
T
= +25°C 0.1
TA = +125°C 1
T
= +25°C 0.25 0.4
TA = -40°C to +125°C 0.6
V
mV
mV
mV
nA
mA
µA
Ω
= +25°C 45 dB
BW Amplifier Unity Gain Frequency TA = +25°C 600 kHz
G Amplifier Transconductance TA = +25°C 4500 mA/V
Note: 4. Production testing of the device is performed at +25°C. Functional operation of the device and parameters specified over the operating temperature
range are guaranteed by design, characterization and process control.
Typical Characteristics
Load Regulation
AL8400/ AL8400Q
Document number: DS35115 Rev. 4 - 2
3 of 13
www.diodes.com
Line Regulation
August 2012
© Diodes Incorporated
Typical Characteristics (cont.)
AL8400 /AL8400Q
Supply Current with Input Voltage
Supply Current with Load Current
FB Voltage Change with Temperature
FB Input Current with Temperature
MOSFET Driving
AL8400/ AL8400Q
Document number: DS35115 Rev. 4 - 2
4 of 13
www.diodes.com
Bipolar Transistor Driving
August 2012
© Diodes Incorporated
Loading...