Datasheet LT8391 (Linear Technology) - 7
| Manufacturer | Linear Technology |
| Description | 60V Synchronous 4-Switch Buck-Boost LED Controller with Spread Spectrum |
| Pages / Page | 34 / 7 — TA = 25°C, unless otherwise noted. Efficiency vs LED Current. (Buck … |
| Revision | A |
| File Format / Size | PDF / 466 Kb |
| Document Language | English |
TA = 25°C, unless otherwise noted. Efficiency vs LED Current. (Buck Region). (Buck-Boost Region). (Boost Region)
Model Line for this Datasheet
Text Version of Document
LT8391 TYPICAL PERFORMANCE CHARACTERISTICS
TA = 25°C, unless otherwise noted. Efficiency vs LED Current Efficiency vs LED Current Efficiency vs LED Current (Buck Region) (Buck-Boost Region) (Boost Region)
100 100 100 90 90 90 80 80 80 70 70 70 60 60 60 EFFICIENCY (%) 50 EFFICIENCY (%) 50 EFFICIENCY (%) 50 40 40 40 30 30 VIN = 36V VIN = 24V 30 20 20 VIN = 12V 0 0.5 1 1.5 2 0 0.5 1 1.5 2 20 LED CURRENT (A) LED CURRENT (A) 0 0.5 1 1.5 2 LED CURRENT (A) 8391 G01 8391 G02 8391 G03
Switching Waveforms Switching Waveforms Switching Waveforms (Buck Region) (Buck-Boost Region) (Boost Region)
VSW1 V V 20V/DIV SW1 SW1 20V/DIV 20V/DIV VSW2 VSW2 VSW2 20V/DIV 20V/DIV 20V/DIV IL 2A/DIV I I L L 2A/DIV 2A/DIV 8391 G04 8391 G05 8391 G06 2µs/DIV 2µs/DIV 2µs/DIV VIN = 36V, ILED = 2A VIN = 24V, ILED = 2A VIN = 12V, ILED = 2A
LED Current vs VIN VIN Shutdown Current VIN Quiescent Current
2.20 3.0 2.8 2.15 2.5 2.6 2.10 2.0 2.05 V V IN = 60V IN = 60V 2.4 2.00 V (µA) 1.5 (mA) IN = 12V I Q I Q 1.95 VIN = 12V 2.2 LED CURRENT (A) 1.0 VIN = 4V 1.90 0.5 V 2.0 IN = 4V 1.85 1.80 0.0 1.8 0 10 20 30 40 50 60 –50 –25 0 25 50 75 100 125 150 –50 –25 0 25 50 75 100 125 150 INPUT VOLTAGE (V) TEMPERATURE (°C) TEMPERATURE (°C) 8391 G07 8391 G08 8391 G09 8391fa For more information www.linear.com/LT8391 7
TA = 25°C, unless otherwise noted. Efficiency vs LED Current Efficiency vs LED Current Efficiency vs LED Current (Buck Region) (Buck-Boost Region) (Boost Region)
100 100 100 90 90 90 80 80 80 70 70 70 60 60 60 EFFICIENCY (%) 50 EFFICIENCY (%) 50 EFFICIENCY (%) 50 40 40 40 30 30 VIN = 36V VIN = 24V 30 20 20 VIN = 12V 0 0.5 1 1.5 2 0 0.5 1 1.5 2 20 LED CURRENT (A) LED CURRENT (A) 0 0.5 1 1.5 2 LED CURRENT (A) 8391 G01 8391 G02 8391 G03
Switching Waveforms Switching Waveforms Switching Waveforms (Buck Region) (Buck-Boost Region) (Boost Region)
VSW1 V V 20V/DIV SW1 SW1 20V/DIV 20V/DIV VSW2 VSW2 VSW2 20V/DIV 20V/DIV 20V/DIV IL 2A/DIV I I L L 2A/DIV 2A/DIV 8391 G04 8391 G05 8391 G06 2µs/DIV 2µs/DIV 2µs/DIV VIN = 36V, ILED = 2A VIN = 24V, ILED = 2A VIN = 12V, ILED = 2A
LED Current vs VIN VIN Shutdown Current VIN Quiescent Current
2.20 3.0 2.8 2.15 2.5 2.6 2.10 2.0 2.05 V V IN = 60V IN = 60V 2.4 2.00 V (µA) 1.5 (mA) IN = 12V I Q I Q 1.95 VIN = 12V 2.2 LED CURRENT (A) 1.0 VIN = 4V 1.90 0.5 V 2.0 IN = 4V 1.85 1.80 0.0 1.8 0 10 20 30 40 50 60 –50 –25 0 25 50 75 100 125 150 –50 –25 0 25 50 75 100 125 150 INPUT VOLTAGE (V) TEMPERATURE (°C) TEMPERATURE (°C) 8391 G07 8391 G08 8391 G09 8391fa For more information www.linear.com/LT8391 7
