Datasheet LT8645S-2 (Analog Devices) - 3
| Manufacturer | Analog Devices |
| Description | 65V, 8A Synchronous Step-Down Silent Switcher with 2.5µA Quiescent Current |
| Pages / Page | 30 / 3 — ELECTRICAL CHARACTERISTICS. The. denotes the specifications which apply … |
| Revision | A |
| File Format / Size | PDF / 3.3 Mb |
| Document Language | English |
ELECTRICAL CHARACTERISTICS. The. denotes the specifications which apply over the full operating
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LT8645S-2
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. PARAMETER CONDITIONS MIN TYP MAX UNITS
Minimum Input Voltage l 3.0 3.4 V VIN Quiescent Current in Shutdown VEN/UV = 0V 0.9 3 µA l 0.9 20 µA VIN Quiescent Current in Sleep VEN/UV = 2V, VFB > 0.97V, VSYNC = 0V 1.7 4 µA l 1.7 20 µA VIN Current in Regulation VOUT = 0.97V, VIN = 6V, ILOAD = 1mA, VSYNC = 0V l 200 500 µA Feedback Reference Voltage VIN = 6V 0.964 0.970 0.976 V VIN = 6V l 0.956 0.970 0.982 V Feedback Voltage Line Regulation VIN = 4.0V to 42V l 0.004 0.025 %/V Feedback Pin Input Current VFB = 1V –20 20 nA BIAS Pin Current Consumption VBIAS = 3.3V, fSW = 2MHz 22 mA Minimum On-Time ILOAD = 2.5A, SYNC = 0V l 40 65 ns ILOAD = 2.5A, SYNC = 2V l 35 60 ns Minimum Off-Time 80 110 ns Oscillator Frequency RT = 221k l 180 210 240 kHz RT = 60.4k l 665 700 735 kHz RT = 18.2k l 1.8 1.95 2.1 MHz Top Power NMOS On-Resistance ISW = 1A 36 mΩ Top Power NMOS Current Limit l 10.5 14 17.5 A Bottom Power NMOS On-Resistance VINTVCC = 3.4V, ISW = 1A 25 mΩ Bottom Power NMOS Current Limit VINTVCC = 3.4V 8.5 11 14 A SW Leakage Current VIN = 42V, VSW = 0V, 42V –1.5 1.5 µA EN/UV Pin Threshold EN/UV Rising l 0.95 1.01 1.07 V EN/UV Pin Hysteresis 45 mV EN/UV Pin Current VEN/UV = 2V –20 20 nA PG Upper Threshold Offset from VFB VFB Falling l 5 7.5 10 % PG Lower Threshold Offset from VFB VFB Rising l –10.5 –8 –5.5 % PG Hysteresis 0.4 % PG Leakage VPG = 3.3V –40 40 nA PG Pull-Down Resistance VPG = 0.1V l 750 2000 Ω SYNC/MODE Threshold SYNC/MODE DC and Clock Low Level Voltage l 0.7 0.9 V SYNC/MODE Clock High Level Voltage l 1.2 1.4 V SYNC/MODE DC High Level Voltage l 2.2 2.55 2.9 V Spread Spectrum Modulation RT = 60.4k, VSYNC = 3.3V 24 % Frequency Range Spread Spectrum Modulation Frequency VSYNC = 3.3V 2.5 kHz TR/SS Source Current l 1.2 2 2.8 µA TR/SS Pull-Down Resistance Fault Condition, TR/SS = 0.1V 220 Ω Rev. A For more information www.analog.com 3 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Applications Related Parts
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. PARAMETER CONDITIONS MIN TYP MAX UNITS
Minimum Input Voltage l 3.0 3.4 V VIN Quiescent Current in Shutdown VEN/UV = 0V 0.9 3 µA l 0.9 20 µA VIN Quiescent Current in Sleep VEN/UV = 2V, VFB > 0.97V, VSYNC = 0V 1.7 4 µA l 1.7 20 µA VIN Current in Regulation VOUT = 0.97V, VIN = 6V, ILOAD = 1mA, VSYNC = 0V l 200 500 µA Feedback Reference Voltage VIN = 6V 0.964 0.970 0.976 V VIN = 6V l 0.956 0.970 0.982 V Feedback Voltage Line Regulation VIN = 4.0V to 42V l 0.004 0.025 %/V Feedback Pin Input Current VFB = 1V –20 20 nA BIAS Pin Current Consumption VBIAS = 3.3V, fSW = 2MHz 22 mA Minimum On-Time ILOAD = 2.5A, SYNC = 0V l 40 65 ns ILOAD = 2.5A, SYNC = 2V l 35 60 ns Minimum Off-Time 80 110 ns Oscillator Frequency RT = 221k l 180 210 240 kHz RT = 60.4k l 665 700 735 kHz RT = 18.2k l 1.8 1.95 2.1 MHz Top Power NMOS On-Resistance ISW = 1A 36 mΩ Top Power NMOS Current Limit l 10.5 14 17.5 A Bottom Power NMOS On-Resistance VINTVCC = 3.4V, ISW = 1A 25 mΩ Bottom Power NMOS Current Limit VINTVCC = 3.4V 8.5 11 14 A SW Leakage Current VIN = 42V, VSW = 0V, 42V –1.5 1.5 µA EN/UV Pin Threshold EN/UV Rising l 0.95 1.01 1.07 V EN/UV Pin Hysteresis 45 mV EN/UV Pin Current VEN/UV = 2V –20 20 nA PG Upper Threshold Offset from VFB VFB Falling l 5 7.5 10 % PG Lower Threshold Offset from VFB VFB Rising l –10.5 –8 –5.5 % PG Hysteresis 0.4 % PG Leakage VPG = 3.3V –40 40 nA PG Pull-Down Resistance VPG = 0.1V l 750 2000 Ω SYNC/MODE Threshold SYNC/MODE DC and Clock Low Level Voltage l 0.7 0.9 V SYNC/MODE Clock High Level Voltage l 1.2 1.4 V SYNC/MODE DC High Level Voltage l 2.2 2.55 2.9 V Spread Spectrum Modulation RT = 60.4k, VSYNC = 3.3V 24 % Frequency Range Spread Spectrum Modulation Frequency VSYNC = 3.3V 2.5 kHz TR/SS Source Current l 1.2 2 2.8 µA TR/SS Pull-Down Resistance Fault Condition, TR/SS = 0.1V 220 Ω Rev. A For more information www.analog.com 3 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Applications Related Parts
