Datasheet LT8645S-2 (Analog Devices) - 3

HerstellerAnalog Devices
Beschreibung65V, 8A Synchronous Step-Down Silent Switcher with 2.5µA Quiescent Current
Seiten / Seite28 / 3 — ELECTRICAL CHARACTERISTICS. The. denotes the specifications which apply …
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DokumentenspracheEnglisch

ELECTRICAL CHARACTERISTICS. The. denotes the specifications which apply over the full operating

ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full operating

Textversion des Dokuments

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 0 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 Package Description Typical Applications Related Parts