LD1610 LDT | Alldatasheet
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Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver LD1610 High Power LED Driver Ver. 1.3 / July. 2013 This document is a general product description and is subject to change without notice. LDT Inc. does NOT assume any responsibility for use of circuits described.
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver
REVISION HISTORY
REV No. Revision Summary Date
1.0 Initial release 2010-11-11
1.1 Added Items
▪ (Page 4) : ‘Power efficiency up to 95%’ ▪ Insert Page13 ▪ (Page 7) : Power Dissipation∙∙∙, Note[1] ▪ (Page 9) : In case, Δif = 38.6%∙∙∙ In case, Δif = 82%∙∙∙ Deleted Items ▪ (Page 10) : 10.5 Thermal considerations 2011-7-28
1.2 Changed absolute maximum rating voltage as below
▪ (Page 7) : VIN 48VDC → 55VDC ▪ (Page 7) : VSW 48VDC → 55VDC 2013-01-25
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver
CONTENTS
- GENERAL DSCRIPTION 2. FEATURES 3. APPLICATIONS 4. BLOCK DIAGRAM 5. PIN DESCRIPTION 6. PIN CONFIGURATION 7. ABSOLUTE MAXIMUM RATINGS 8. ELECTRICAL CHARACTERISTICS 9. CIRCUIT DESCRIPTION 10. APPLICATION INFORMATION 11. PACKAGE INFORMATION
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver 1. GENERAL DESCRIPTION The LD1610 is a continuous mode inductive step-down converter, designed for driving single or multiple series connected High Power LEDs with a minimum number of external components. It operates from an input voltage range of 7V to 40V and provides an externally adjustable output current up to 1.0A depending upon input voltage and external components. The LD1610 has internal switching transistor, regulator and output current sensing circuit, which uses an external resistor to set the nominal average output current. The LED dimming can be controlled via pulse width modulation (PWM) through DIM pin. Additionally, to ensure the system reliability, the LD1610 has internal thermal shutdown circuit. 2. FEATURES
- 7V ~ 40V input range generates maximum 1.0A output constant current.
- Regulation voltage is 4.5V.
- Over temperature thermal protection
- Over voltage circuit protection
- External dimming control PIN
- High efficiency output design
- Power efficiency up to 95%
- Package : 8-pin Exposed SOP 4. APPLICATIONS
- MR16 lighting
- DC/DC LED driver
- Automotive lighting
- Offline LED lamps PART NUMBER PACKAGE Ta LD1610-SP 8 SOP -40°C to 85 °C 3. ORDERING INFORMATION
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver 5. BLOCK DIAGRAM 6. PIN DISCRIPTION PIN NAME DESCRIPTION PIN No. VIN Input voltage (7V ~ 40V) 1 VDD Internal regulator output. Connects decoupling capacitor to this pin with 1.0uF capacitor. 2 AGND Analog ground 3 DIM Dimming control terminal. Connect to VDD if not used. 4 DGND Digital ground 5 CS Current sense connection 6 R Output current level setting resistor. Connects a resistor from this pin to ground for output current setting. 7 SW Switch output terminal 8 Pulse Generator Thermal Shutdown Control Logic Voltage Regulator VDD DIM DGND AGND SW R CS REF VIN
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver 7. PIN CONFIGURATION SW R CS DGND VIN VDD AGND DIM
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver (Unless otherwise stated, GND=0V, TA=25℃) (Unless otherwise stated, VIN=12V, GND=0V, TA=25℃) PARAMETERS SYMBOL RATING UNIT VIN Supply Voltage VIN 55VDC V SW Voltage VSW 55VDC V Power Dissipation PD 2.3[1] W Operating Ambient Temperature TA -40 to 85 ℃ Operating Junction Temperature TJ -40 to 150 ℃ Parameter Symbol Condition Min. Typ. Max. Unit DC Input Voltage VIN DC to VIN 7 40 V SW Frequency FSW 500[2] kHz SW On-Resistance RON ILED = 500mA 0.5 Ω VDD Output Voltage VDD 4.5 V LED Output Current ILED 350 1000 mA Quiescent Current 1.5 mA Thermal Shutdown 140 ℃ 8. ABSOLUTE MAXIMUM RATINGS 9. ELECTRICAL CHARACTERISTICS Note [1] :Based on JEDEC-51. [2] :Frequency depends on input voltage, inductance and output current.
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver 10. CIRCUIT DESCRIPTION During the charging operation, the turning on of the internal power NDMOS stores the input energy in an inductor. When the NDMOS is turned off during the OFF time, the stored energy will deliver to the output through the fly-back diode D, producing the ILED current through the LEDs. Since LD1610 is designed with a high efficient constant off time controlling technique, the OFF time is fixed at 1.5μs (typical), it is important to make sure the supply voltage is less than 2 times the forward voltage drop across the LEDs. 11. APPLICATION INFORMATION The LD1610 is a buck mode inductive DC-DC converter, with an internal switch, designed for driving single or multiple LEDs in series up to 1.0A output current. VIN input voltage is 7~40V DC voltage. The constant current operation is Pulse Frequency Modulation (PFM) method. The off time of switching is fixed at 1.5us. So, the on time of switching depends on DIM pin signal, CS pin voltage and thermal voltage.
11.1 Typical Application Circuit
L if Va R ia VIN VDD AGND DIM SW R CS DGND LD1610 D (option)
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver
11.2 Setting the Output Current with Resistor (R)
If CS pin voltage is below 0.2V then the switch is on. CS pin voltage is over 0.2V then the switch is off. So, typical peak to peak ripple current in the inductor is 15% of LED current (if). if = 350mA setting ia = if + Δif/2 = 350mA + 350mA x 0.15/2 = 376.25mA Δif ≈ 15%x if Va = R x ia R = Va / ia = 0.2V / 376.25mA ≈ 533mΩ if = 500mA setting ia = if + Δif/2 = 500mA + 500mA x 0.15/2 = 538mA Δif ≈ 15%x if Va = R x ia R = Va / ia = 0.2V / 538mA ≈ 372mΩ if = 1000mA setting ia = if + Δif/2 = 1000mA + 1000mA x 0.15/2 = 1075mA Δif ≈ 15%x if Va = R x ia R = Va / ia = 0.2V / 1075mA ≈ 186mΩ
11.3 Inductor Selection
Higher values of inductance are recommended at higher supply voltage in order to minimize errors due to switching delays, which results in increased ripple and low efficiency. High value of inductance also results in a smaller change in output current (if) over the supply voltage range. L = VLED x toff / Δif VLED = Vf x N N = # of LEDs in series Toff = 1.5us Δif = 15% x if If N = 3, if = 350mA, Vf = 3V L = 3V x 3 x 1.5us / ( 0.15 x 350mA ) ≈ 257uH In case, Δif = 39%x if , L = 3V x 3 x 1.5us / ( 0.39 x 350mA ) ≈ 100uH In case, Δif = 82%x if , L = 3V x 3 x 1.5us / ( 0.8 x 350mA ) ≈ 47uH
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver
11.4 Layout Considerations
For high frequency and high current switching power supplies, layout is an important design step. To reduce switching losses, the switch rise and fall times are made as short as possible. Minimize the length and area of all traces connected to the switch and always use a ground plane under the switching regulator to inter-plane coupling. The loop including LEDs, the PFM switch and schottky diode contains high current rising and falling and should be kept as short as possible. The input capacitor needs not only to be close to the VIN pin, but also to the GND pin in order to reduce the supply ripple.
11.5 Components Selection
Table 1. Recommended Capacitor Manufacturers Table 2. Recommended Inductor Manufacturers
than two times of VIN and the average current through the diode should be 2 x ILED or greater. Table 3. Recommended Diode Manufacturers
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver 11.6 Efficiency vs. Input Voltage TA = 25℃, VFORWARD-LED = 3.25V @ 350mA, 75.00% 80.00% 85.00% 90.00% 95.00% 100.00% 12 14 16 18 20 22 24 26 28 30 VIN(V) 75.00% 80.00% 85.00% 90.00% 95.00% 100.00% 20 22 24 26 28 30 32 34 36 38 40 VIN(V) 75.00% 80.00% 85.00% 90.00% 95.00% 100.00% 6 8 10 12 14 16 18 20 22 24 VIN(V)
1 LED
2 LED
3 LED
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver
11.7 Typical Performance Characteristics
TA = 25℃, VFORWARD-LED = 3.25V @ 350mA, N = # of LEDs in series, unless otherwise noted ILED V S V IN L=220uH, N=1, V f=3. 25V , C2=4. 7uF 0 mA 100 mA 200 mA 300 mA 400 mA 500 mA 600 mA 700 mA 800 mA 900 mA 6 8 10 12 14 16 18 20 22 24 V IN (V ) ILED 0.5Ω R=0.5Ω ILED V S V IN L=220uH, N=3, V f=3. 25V , C=4. 7uF 0 mA 100 mA 200 mA 300 mA 400 mA 500 mA 600 mA 700 mA 800 mA 900 mA 12 14 16 18 20 22 24 26 28 30 V IN (V ) ILED 0.5Ω R=0.5Ω
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver ILED V S V IN L=220uH, N=5, V f=3. 25V , C=4. 7uF 0 mA 100 mA 200 mA 300 mA 400 mA 500 mA 600 mA 700 mA 800 mA 900 mA 20 22 24 26 28 30 32 34 36 38 40 V IN (V ) ILED 0.5Ω R=0.5Ω
Ver1.3 LDT Inc. WE bldg. 5F, 126-33 Han-dle 1ro, Seobuk-gu, Cheonan, Chungnam, korea, 331-220 LD1610 High Power LED Driver 12. PACKAGE INFORMATION (ESOP)