LED Drivers for MR16 Lamps

1. LED Drivers for MR16 Lamps
NCL30160/NCL30161
1

2. LED Driver DC-DC Decision Tree
Wide input Voltage
LED Driver Selector
Vin < 40V
Step-down
(Buck)
Vout < Vin
Step-up
(Boost)
Vout > Vin
SEPIC/Buck-Boost
Vout < = > Vin
NCP3065/6
<350mA
Is Vout > 40V
YES
Determine
Iout?
> 1.2A
NO
< 1.2A
NCP3065/6
Boost
Controller
2 • Template • Nov-12
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> 1.3A
NCP3065/6
Boost
Converter
What is the
Switch current
NCP3163 up to
3A Switch
CAT4201
Hysteretic Buck
Converter
NCP3065/6
Boost Controller
Confidential Proprietary
NCP3065/6
Buck
Converter
NCP3065/6
Buck
Controller
NCL30160
Buck
Converter
< 1.3A
NCL30161
Buck
Controller
NCL30100
Buck
Controller

3. NCL30160 – HB-LED Regulator
Value Proposition
The NCL30160 is an NFET hysteretic step-down, constant-current driver for high power LEDs. A dedicated PWM
input (DIM) enables wide range of pulsed dimming. Switching frequency up to 1.4 MHz, minimizing space and
cost. Intended for continuous conduction mode operation, thus no output capacitor is needed
Unique Features
• 50
mΩ integrated MOSFET
• Capable
of 100% max
duty cycle
Benefits
Application Data
• High efficiency solution
• Wide input voltage range
capability
• Input
voltage from 6.3 V to
40 V input
Others Features
• Up to 1.4 MHz switching frequency
• Dedicated PWM dimming pin / low power
• No control loop compensation required
• 1.5 A average current capability
shutdown
Market & Applications
•
•
Architectural: MR-16
Area Lighting: Light strips, Landscape, Under-cabinet
High Efficiency 50mΩ
MOSFET
Dedicated DIM Pin
Ordering & Package Information
•
•
3 • Template • Nov-12
3
SOIC-8
NCL30160
Confidential Proprietary

4. NCL30160 Key Features
Vcc operation
from 6.3-40 V
LEDs are
connected
to Vin
1 A /50 mΩ
Integrated MOSFET
Dedicated
Dimming Input
Adjustable
current sense
threshold
Adjustable
Initial off-time
control
4 • Template • Nov-12
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Confidential Proprietary

5. Common Vin Multi-string Connection
D1
D4
D10
D6
D11
D13
D3
D2
D13
1u
1u
L2
NCL
30160
L1
NCL
30160
R2
R3
L3
1u
L3
NCL
30160
R3
Reduce the connection lines for the multi-string LEDs
5 • Template • Nov-12
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Confidential Proprietary
D9
D8
D8
1u
R1
D10
D9
D15
NCL
30160
D12
D12
D7
D17
D5

6. Functional Description
• The NCL30160 uses a hysteretic control of the output current. It aims to
keep the peak and valley of the current ripple at a set threshold level.
• When the FET is on and the current is rising, the current is continuously
sensed through a resistor until it sees the peak current, and then turns
off.
• When the FET is off and the current is falling, a timer is used for the offtime duration. When the off-time ends, the valley current is sensed, and
adjusts the next off-time if needed.
6 • Template • Nov-12
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7. Peak Current – Fixed Off Time
Operating Principle
D1
VIN
CIN
L1
No Output Cap
LED
LX
VIN
DIM/Enable
ROT
CS
NCL30160
RSENSE
ROT
PWM
VCC
GND
Cvcc
•Red Path show current flow when switch is ON
•Green Path shows current flow when switch is OFF
7 • Template • Nov-12
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8. Off-Time Setting Resistor
• Since the current is not sensed while the MOSFET is off, a
timer is used to set the FET off-time duration.
• The off-time setting resistor sets the initial FET off-time only,
when the part starts up. This allows the LED current to
quickly reach its expected level.
• To pick the value of the off-time setting resistor:
– Calculate off-time:
– Calculate resistor value:
8 • Template • Nov-12
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9. Dimming Performance
• Dimming works by pulsewidth modulation (PWM)
on the DIM/Enable pin
• The duty ratio of the PWM
is equivalent to the
amount of dimming
9 • Template • Nov-12
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10. NCL30160 Schematic
• MR-16 12 Vac / up to 1 A application
10 • Template • Nov-12
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11. Efficiency Performance
350 mA / 3.5 Vf
11 • Template • Nov-12
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750 mA / 3.5 Vf
Confidential Proprietary

12. Output Current Line Regulation
500 mA / 3 LEDs / 3.5 Vf
12 • Template • Nov-12
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500 mA / 68 uH / 3.5 Vf

13. 12 Vac Buck Operation
• Recall that in a buck topology,
current only flows when Vin is
greater than Vout
Iout
• Since the current isn’t always Vin
flowing, you will need to use a
smaller Rsense value to
reach a desired value
average current.
• So, NCL30160 voltage varies
with 12 Vac input waveform
No current flows
when Vin < Vout
13 • Template • Nov-12
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Confidential Proprietary

14. Electronic Ballast Compatibility Table
3 LEDs in series, 2 channels in parallel, 1 A
Parameter
VIN
IIN
PIN
Power Factor
VLED
ILED
PLED
Efficiency
Lightech LET-75
120.5 V
72.08 mA
7.746 W
0.892
8.77 V
0.638 A
6.669 W
86.1%
Hatch RS12-80M
120.4 V
76.14 mA
8.254 W
0.900
9.14 V
0.685 A
7.157 W
86.7%
Lightech LET-60
120.2 V
72.65 mA
7.862 W
0.900
8.84 V
0.647 A
6.779 W
86.2%
Eurofase 0084
120.3 V
68.98 mA
7.244 W
0.873
8.70 V
0.606 A
6.342 W
87.6%
Hatch RS12-30MLED
120.2 V
83.11 mA
9.491 W
0.950
9.26 V
0.715 A
7.461 W
78.6%
Lightech LET-60
120.1 Vac
77.08 mA
8.057 W
0.870
4.69 V
0.942 A
6.703 W
83.2%
Eurofase 0084
120.0 Vac
73.81 mA
7.693 W
0.869
4.53 V
0.904 A
6.452 W
83.9%
Hatch RS12-30M-LED
120.1 Vac
90.91 mA
9.989 W
0.915
5.45 V
1.07 A
7.618 W
76.3%
2 LEDs in series, 2 channels in parallel, 0.7 A
Parameter
VIN
IIN
PIN
Power Factor
VLED
ILED
PLED
Efficiency
14 • Template • Nov-12
14
Lightech LET-75
120.2 Vac
75.77 mA
7.925 W
0.870
4.58 V
0.927 A
6.589 W
83.1%
Hatch RS12-80M
120.1 Vac
78.26 mA
8.414 W
0.895
4.97 V
0.986 A
7.017 W
83.4%
Confidential Proprietary

15. NCL30160 Application Schematic
• 12 Vdc or 24 Vdc / up to 1 A application
15 • Template • Nov-12
15
Confidential Proprietary

16. Efficiency Performance
300 mA
1A
4 LEDs
4 LEDs
3 LEDs
3 LEDs
2 LEDs
2 LEDs
16 • Template • Nov-12
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17. Design Tools / Support
• Excel based tool
• Eval boards
• NCL30160GEVB
• Design notes
• 24 V LED Light Strip
17 • Template • Nov-12
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Confidential Proprietary

18. Comparison
NCL30160
6.3 - 40V
XXXX
ZXLD1360
7 - 30 V
XXXX
PT4115
8 - 30V
XXXX
LM3404
6 - 42 V
NCP3065
3 - 40 V
NCL30100
6 - 18 V
Input Voltage
Continuous
Output Current
Switch
Fsw
Sense Method
Duty Cycle
FB Voltage
1.0 A
1.0 A
1.2 A
1.2 A
1.2 A
N/A
50mohm
50 - 1400 kHz
Peak
100% max
0.2 V
1000mohm
50 - 500 kHz
Average
70% max
1.25 V
600mohm
100 - 1000 kHz
Peak
~90% max
1.23 V
750mohm
50 - 1000 kHz
Peak
~ 70% max
0.2 V
Controller
50 - 500 kHz
Peak
~ 85% max
1.2 V
Topology
Buck
Buck
Buck
Buck
1000mohm (eq)
50 - 250 kHz
Average
~ 85% max
0.25 V
Buck, Boost,
Buck/Boost
Package Rja
85 °C/W
125 °C/W
45 °C/W
155 / 50 °C/W
85 C/W
178 C/W
Package
SO-8
TSOT-23-5
SO-8EP
SO-8 / SO-8EP
SO-8 / PDIP-8 /
DFN-8
TSOP-6
Controller
Dedicated
Dimming Pin
Thermal
Protection
Control
Methodology
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
NO
NO
YES
NO
YES
YES
YES
NO
Hysteretic
Hysteretic
Hysteretic
Hysteretic
Hysteretic
Hysteretic
18 • Template • Nov-12
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Confidential Proprietary
Buck

19. NCL30161 - Buck Regulator for
Driving High Power LEDs
Value Proposition
The NCL30161 is a hysteretic step−down, constant−current driver for high power LEDs. Ideal for automotive,
industrial and general lighting applications utilizing minimal external components.
Typical Application diagram & Package info
Features
•
•
•
•
•
•
•
•
VIN Range 6.3 V to 40 V
Short LED Shutdown Protection
No Control Loop Compensation Required
Adjustable LED Current
Single Pin Brightness and Enable/Disable Control Using PWM
Supports All−Ceramic Output Capacitors and Capacitor−less Outputs
Thermal Shutdown Protection
Capable of 100% Duty Cycle Operation
With
external
mosfet
Benefits
• Hysteretic control provides good power supply rejection and fast
response during load transients
• Dedicated PWM input (DIM/EN) enables a wide range of pulsed
dimming
• Uses smaller external components minimizing space and cost.
• Protection features include resistor−programmed constant LED
current, shorted LED protection, under−voltage and thermal
shutdown.
Market & Applications
•
•
•
•
•
LED Driver
Constant Current Source
Automotive Lighting
General Illumination
Industrial Lighting
19 • Template • Nov-12
19
Ordering info & Support
NCL30161MNT2G
Package – 3mm x 3mm DFN10
Confidential Proprietary

20. Smaller Size Solution
1.8 mm*3.8 mm*1 mm
13 mm*mm
L1
1
VIN
2
NCL30161
NTLJF4156N
3mm*3mm
D2
U1A
10
9
11
7
6
C1
Gate
CS
VIN
NC
/DIMM/ENGND
NC
NC
ROT
VCC
R2
C2
ROT
0
1
2
14
4
5
L1
0
VIN
1
Analog Dimming
D2
NCL30160
R3
R2
U1A
5mm*6mm*1.1mm
36.8 mm*mm
10
9
11
7
6
C1
0
Gate
CS
VIN
NC
/DIMM/ENGND
NC
NC
ROT
VCC
ROT
1
2
14
4
5
R2
C2
0
20 • Template • Nov-12
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Confidential Proprietary
2

21. Increase the input voltage
L1
VIN
1
R1
1k
D2
Q1
C1
D1
U1A
C1
0
10
9
11
7
6
Gate
CS
VIN
NC
/DIMM/ENGND
NC
NC
ROT
VCC
ROT
1
2
14
4
5
R2
C2
0
21 • Template • Nov-12
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2

22. Thank you
22 • Template • Nov-12
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23. Block Diagram
50mΩ
MOSFET
26 • Template • Nov-12
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