Datasheet LT3922 (Analog Devices) - 8
| Manufacturer | Analog Devices |
| Description | 36V, 2A Synchronous Step-Up LED Driver |
| Pages / Page | 32 / 8 — Typical perForMance characTerisTics VIN = 12V, TA = 25°C, unless … |
| File Format / Size | PDF / 2.5 Mb |
| Document Language | English |
Typical perForMance characTerisTics VIN = 12V, TA = 25°C, unless otherwise noted. FB OPENLED Threshold
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LT3922
Typical perForMance characTerisTics VIN = 12V, TA = 25°C, unless otherwise noted. FB OPENLED Threshold VISP – VISN SHORTLED Threshold Power Switch On-Resistance
1.20 180 350 RISING TOP SWITCH FALLING BOTTOM SWITCH 1.15 170 300 250 1.10 160 ANCE (mΩ) 200 1.05 150 TLED THRESHOLD (mV) 150 1.00 140 SHOR 100 ISN FB OPENLED THRESHOLD (V) 0.95 – V 130 50 V ISP POWER SWITCH ON–RESIST 0.90 120 0 –45 –20 5 30 55 80 105 130 155 –45 –20 5 30 55 80 105 130 155 –45 –20 5 30 55 80 105 130 155 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 3922 G28 3922 G29 3922 G30
Efficiency vs VIN Efficiency vs ILED Regulated FB Voltage
100 100 1.23 ILED = 400mA VIN = 12V 98 11 LEDs (VOUT ~ 33V) 98 fSW = 2MHz 96 96 1.22 94 94 92 92 1.21 90 90 TAGE (V) 88 88 1.20 EFFICIENCY (%) EFFICIENCY (%) FB VOL 86 86 84 84 6 LED (V 1.19 OUT ~ 18V) f 82 SW = 400kHz 9 LED (V 82 OUT ~ 27V) fSW = 2MHz 12 LED (VOUT ~ 36V) 80 80 1.18 6 8 10 12 14 16 18 20 22 24 26 28 30 0 200 400 600 800 1000 –45 –20 5 30 55 80 105 130 155 VIN (V) ILED (mA) TEMPERATURE (°C) 3922 G31 3922 G32 3922 G33
PWMTG ON Voltage PWM Driver Propagation Delay FB OVLO Threshold
12 200 1.33 TURN OFF RISING FALLING TURN ON 11 1.30 160 TAGE (V) (V) Y (ns) 10 1.27 PWMTG 120 – V TION DELA 9 1.24 AGA V OUT 80 8 PROP 1.21 FB OVLO THRESHOLD VOL CPWMTG = 2.2nF (C0G type) 7 40 1.18 –45 –20 5 30 55 80 105 130 155 –45 –20 5 30 55 80 105 130 155 –45 –20 5 30 55 80 105 130 155 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 3922 G34 3922 G35 3922 G36 3922fa 8 For more information www.linear.com/LT3922 Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
Typical perForMance characTerisTics VIN = 12V, TA = 25°C, unless otherwise noted. FB OPENLED Threshold VISP – VISN SHORTLED Threshold Power Switch On-Resistance
1.20 180 350 RISING TOP SWITCH FALLING BOTTOM SWITCH 1.15 170 300 250 1.10 160 ANCE (mΩ) 200 1.05 150 TLED THRESHOLD (mV) 150 1.00 140 SHOR 100 ISN FB OPENLED THRESHOLD (V) 0.95 – V 130 50 V ISP POWER SWITCH ON–RESIST 0.90 120 0 –45 –20 5 30 55 80 105 130 155 –45 –20 5 30 55 80 105 130 155 –45 –20 5 30 55 80 105 130 155 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 3922 G28 3922 G29 3922 G30
Efficiency vs VIN Efficiency vs ILED Regulated FB Voltage
100 100 1.23 ILED = 400mA VIN = 12V 98 11 LEDs (VOUT ~ 33V) 98 fSW = 2MHz 96 96 1.22 94 94 92 92 1.21 90 90 TAGE (V) 88 88 1.20 EFFICIENCY (%) EFFICIENCY (%) FB VOL 86 86 84 84 6 LED (V 1.19 OUT ~ 18V) f 82 SW = 400kHz 9 LED (V 82 OUT ~ 27V) fSW = 2MHz 12 LED (VOUT ~ 36V) 80 80 1.18 6 8 10 12 14 16 18 20 22 24 26 28 30 0 200 400 600 800 1000 –45 –20 5 30 55 80 105 130 155 VIN (V) ILED (mA) TEMPERATURE (°C) 3922 G31 3922 G32 3922 G33
PWMTG ON Voltage PWM Driver Propagation Delay FB OVLO Threshold
12 200 1.33 TURN OFF RISING FALLING TURN ON 11 1.30 160 TAGE (V) (V) Y (ns) 10 1.27 PWMTG 120 – V TION DELA 9 1.24 AGA V OUT 80 8 PROP 1.21 FB OVLO THRESHOLD VOL CPWMTG = 2.2nF (C0G type) 7 40 1.18 –45 –20 5 30 55 80 105 130 155 –45 –20 5 30 55 80 105 130 155 –45 –20 5 30 55 80 105 130 155 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 3922 G34 3922 G35 3922 G36 3922fa 8 For more information www.linear.com/LT3922 Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
