Document
Light Emitting Diode (LED) Driver
Features Supply voltage from 4.0 to 40 V Output driving current up to 0.8 A
(IL7150A), 1.5 A (IL7150) Current consumption 4 mA ESD protection up to 2kV Temperature range from - 40 to +85 C Only 5 external components required
TECHNICAL DATA
IL7150, IL7150A
TO-263-5L IL7150D2T IL7150AD2T
Applications
Automotive DC/DC LED Driver Lighting Equipments Light Indicators
Device IL7150D2T IL7150AD2T
ORDERING INFORMATION
Operating Temperature Range
Package
TA = -40 to 125 C
TO-263 TO-263
Packing Tape & Reel Tape & Reel
Description
IL7150, IL7150A (functional equivalent AMC7150 of ADDtek) - LED (Light Emitting Diode) driver with peak output current 0.8A (IL7150A) & 1.5A (IL7150).
Microcircuit designed for driving of power LEDs in the wide range of supply voltages and load currents with peak output currents 0.8 & 1.5A. Main application areas are automotive, DC/DC LED driver, lighting equipments and light indicators.
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2012, June, Rev. 00
IL7150
Table 1. Contact Pad Description
Contact pad Number
Pin Number
Symbol
01 01 VCC
02, 03, 04, 05
02
CS
09, 15
03 GND
06, 07
04 OUT
08 05 OSC
Function Supply voltage input Current sensor input Ground Driver output Oscillator output
Note: Contact pads 10 – 14 are purposed only for testing during IC manufacturing and are not used by customer
Vcc CS
OUT
+-
OCS
Control unit Oscilator
Driver
GND Fig. 1 – Block Diagram
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2012, June, Rev. 00
IL7150
Table 3. Recommended Operation Conditions
Parameter
Supply voltage Junction temperature
Symbol
VCC TJ
Target Min Max 4.0 40 125
Unit
V oC
Table 4. Maximum Ratings
Parameter
Supply voltage Output voltage Junction temperature Storage temperature
Symbol
VCC VO TJ TSTG
Target
Min Max -0.3 40 -0.3 40 150 -60 150
Unit
V V oC oC
* Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device.
These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied.
Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
Table 5. Electrical Characteristics
Symbol
Parameter
Testing mode
ICC Supply current
4.0 V VCC 40 V
Output saturation voltage VCC = 5.0 V
IZ7150 VDP
IO = 1.0 A IO = 1.5 A
IZ7150A
IO= 0.5 A IO= 0.8 A
IOL Output leakage current VCC = 40 V
VCS DCMAX
ICH
Current sensor voltage
Max duty cycle Capacitor charging current
VCC = 5.0 V VCC = 5.0 V VCC = 5.0 V
Value
Min Max
-
4.0 4.4
1.3 1.4
3.0 - 3.0
1.3 1.4
3.0 3.0
-
300 330
300 360 270 396
50 99
20 50
Ambient tempera
ture, °C
25 10 -40; 85
25 10; -40; 85
Unit mA
V
A mV % A
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2012, June, Rev. 00
+ G1 -
R1
VCC CS C1
OCS C2
GND
IL7150
D1 OUT
VD1
L1 VD2
VD3
C1 – capacitor 47 F ± 10%; C2 – capacitor 680 pF ± 10%; D1 – microcircuit ; G1 – supply voltage source from 4.0 to 40 V; L1 – inductance coil 220 H ± 10%; R1 – resistor 330 m ± 1%; VD1 – Zener diode with stabilization voltage 40 V (1N5819 or equivalent); VD2, VD3 - LEDs
Fig. 2. Application Diagram
Functionality Starting current is regulated in the range from few milliamps up to 1.5 A. The regulation is performed by means of PWM (pulse-width modulation).Load is repetitively connected to the supply voltage via output switch. Changing of pulses porosity, adjusts average output voltage that allows regulating of output current. Inductive energy storage is applied in the circuit because of output voltage is pulse Input decoupling capacitor Input decoupling capacitor C1 regulates the input voltage and rejects switching interference. Limiting diode Zener diode with fast recovering VD1 is recommended as limiting diode. High reverse recovery current will cause on R1 voltage drop more than 330 mV, therefore switch that has to be on will turned off.
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2012, June, Rev. 00
IL7150
LED driving current
Resistor R1 determine max output peak current to the LED.
Output peak current IO, flowing thought the LED, can be calculated by formula:
IO
330mV R1
.
Average LED current is determined by amplitude of oscillating (pulsating) current,
that depends on inductivity of coil L1. For example , average current of LED is 550 mA
(pulsating) current is 100 mA. Then:
R1 330mV 0,55 . 550mA 0,5 100mA
In order to driving current not exceed recommended max rating 1.5 A for IL7150,
(0.8A for IL7150A), R1 value has to be more than 200 m.
Inductor
The Inductor L1 stores energy during switch turn-on period and discharge driving
current to LEDs via flywheel diode while switch turn-off. In order to reduce the current
ripple on LEDs, the L value should high enough to keep the system working at continuousconduction mode that inductor current won’t fall to zero.
Since in steady-state operation the waveform must repeat from one time period to
the next, the integral of the inductor voltage VL over one time period m.