Datasheet LT3745 (Analog Devices) - 4
| Manufacturer | Analog Devices |
| Description | 16-Channel 50mA LED Driver with Buck Controller |
| Pages / Page | 28 / 4 — e lecTrical characTerisTics The. denotes the specifications which apply … |
| File Format / Size | PDF / 394 Kb |
| Document Language | English |
e lecTrical characTerisTics The. denotes the specifications which apply over the full operating
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LT3745
e lecTrical characTerisTics The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = 12V, VCC = 3.3V, VEN/UVLO = 1.5V, VFB = 1.5V, VISP = VISN = 0V, RT = 105k, RISET = 60.4k, CCAP = 0.47µF to VIN, unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Gate Driver
VBIAS CAP Bias Voltage (VIN – VCAP) 7V < VIN < 55V 6.5 6.8 7.1 V ICAP CAP Bias Current Limit (VIN – VCAP) = VBIAS – 0.5V 22 mA GATE High Level (VIN – VGATE) IGATE = –100mA 0.4 V GATE Low Level (VGATE – VCAP) IGATE = 100mA 0.3 V GATE Rise Time CGATE = 3.3nF to VIN 30 ns GATE Fall Time CGATE = 3.3nF to VIN 30 ns
LED Driver
VISET Trimmed ISET Pin Voltage l 1.181 1.205 1.229 V LEDxx Operating Voltage VIN = 48V, VISP = VISN = VLEDxx l 36 V LEDxx Leakage Current LED Channel Off, VIN = 48V, 0.2 µA VISP = VISN = 36V, VLEDxx = 24V ILED LED Constant Sink Current VISP = VISN = 5V, VLEDxx = 1V REGDC = 0x00 l 23.5 25.3 27 mA REGDC = 0x20 l 48 50.5 53 mA REGDC = 0x3F l 71 74 77 mA ∆ILEDC Current Mismatch Between Channels VISP = VISN = 5V, VLEDxx = 1V, l ±1 ±3 % REGDC = 0x20 (Note 6) ∆ILEDD Current Mismatch Between Devices VISP = VISN = 5V, VLEDxx = 1V, l ±1 ±3 % REGDC = 0x20 (Note 7) ∆ILINE LED Current Line Regulation VISP = VISN = 5V, VLEDxx = 1V, 0.1 0.2 %/V REGDC = 0x20, VCC = 3V to 5.5V (Note 8) ∆ILOAD LED Current Load Regulation VISP = VISN = 5V, REGDC = 0x20, 0.1 0.2 %/V VLEDxx = 1V to 3V (Note 9) VOPEN Open LED Threshold VISP = VISN = 5V, VLEDxx Falling 0.35 V VSHT Short LED Threshold VISP = VISN = 5V, VLEDxx Rising 3.7 3.9 4.1 V TLEDON Minimum LED On-Time VISP = VISN = 5V, REGGS = 0x001 0.5 µs PWMCK LOGIC VCC = 3V to 5.5V High Level Voltage 2.4 VCC V Low Level Voltage 0 0.6 V
Thermal Protection
ITSET TSET Output Current VTSET = 1V l 19.0 19.8 20.6 µA TSET Over Temperature Threshold TA = 25°C 510 mV
Serial Data Interface
Single-Ended Input (Note 10) VCC = 3V to 5.5V VSIH High Level Voltage 2.4 VCC V VSIL Low Level Voltage 0 0.6 V ISI Single-Ended Input Current VCC = 3V to 5.5V, SI = VCC or GND –0.2 0.2 µA Single-Ended Output (Note 10) VCC = 3V to 5.5V V VSOH High Level Voltage ISO = –1mA VCC – 0.1 V VSOL Low Level Voltage ISO = 1mA 0.1 V 3745f 4 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Timing Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Application Package Description Typical Application Related Parts
e lecTrical characTerisTics The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = 12V, VCC = 3.3V, VEN/UVLO = 1.5V, VFB = 1.5V, VISP = VISN = 0V, RT = 105k, RISET = 60.4k, CCAP = 0.47µF to VIN, unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Gate Driver
VBIAS CAP Bias Voltage (VIN – VCAP) 7V < VIN < 55V 6.5 6.8 7.1 V ICAP CAP Bias Current Limit (VIN – VCAP) = VBIAS – 0.5V 22 mA GATE High Level (VIN – VGATE) IGATE = –100mA 0.4 V GATE Low Level (VGATE – VCAP) IGATE = 100mA 0.3 V GATE Rise Time CGATE = 3.3nF to VIN 30 ns GATE Fall Time CGATE = 3.3nF to VIN 30 ns
LED Driver
VISET Trimmed ISET Pin Voltage l 1.181 1.205 1.229 V LEDxx Operating Voltage VIN = 48V, VISP = VISN = VLEDxx l 36 V LEDxx Leakage Current LED Channel Off, VIN = 48V, 0.2 µA VISP = VISN = 36V, VLEDxx = 24V ILED LED Constant Sink Current VISP = VISN = 5V, VLEDxx = 1V REGDC = 0x00 l 23.5 25.3 27 mA REGDC = 0x20 l 48 50.5 53 mA REGDC = 0x3F l 71 74 77 mA ∆ILEDC Current Mismatch Between Channels VISP = VISN = 5V, VLEDxx = 1V, l ±1 ±3 % REGDC = 0x20 (Note 6) ∆ILEDD Current Mismatch Between Devices VISP = VISN = 5V, VLEDxx = 1V, l ±1 ±3 % REGDC = 0x20 (Note 7) ∆ILINE LED Current Line Regulation VISP = VISN = 5V, VLEDxx = 1V, 0.1 0.2 %/V REGDC = 0x20, VCC = 3V to 5.5V (Note 8) ∆ILOAD LED Current Load Regulation VISP = VISN = 5V, REGDC = 0x20, 0.1 0.2 %/V VLEDxx = 1V to 3V (Note 9) VOPEN Open LED Threshold VISP = VISN = 5V, VLEDxx Falling 0.35 V VSHT Short LED Threshold VISP = VISN = 5V, VLEDxx Rising 3.7 3.9 4.1 V TLEDON Minimum LED On-Time VISP = VISN = 5V, REGGS = 0x001 0.5 µs PWMCK LOGIC VCC = 3V to 5.5V High Level Voltage 2.4 VCC V Low Level Voltage 0 0.6 V
Thermal Protection
ITSET TSET Output Current VTSET = 1V l 19.0 19.8 20.6 µA TSET Over Temperature Threshold TA = 25°C 510 mV
Serial Data Interface
Single-Ended Input (Note 10) VCC = 3V to 5.5V VSIH High Level Voltage 2.4 VCC V VSIL Low Level Voltage 0 0.6 V ISI Single-Ended Input Current VCC = 3V to 5.5V, SI = VCC or GND –0.2 0.2 µA Single-Ended Output (Note 10) VCC = 3V to 5.5V V VSOH High Level Voltage ISO = –1mA VCC – 0.1 V VSOL Low Level Voltage ISO = 1mA 0.1 V 3745f 4 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Timing Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Application Package Description Typical Application Related Parts
