Datasheet LTC7893 (Analog Devices) - 5

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Data Sheet LTC7893
(Specifications are at TJ = -40°C to +125°C for the minimum and maximum values, TA = 25°C for the typical values, VBIAS = 12V, RUN = 5V, VPRG = Floating, EXTVCC = 0V, DRVSET = 0V, DRVUV = 0V, DTCA and DTCB = 0V, unless otherwise noted.)
PARAMETER SYMBOL CONDITIONS/COMMENTS MIN TYP MAX UNITS
RUN Pin ON Threshold RUN rising 1.15 1.20 1.25 V RUN Pin Hysteresis 120 mV
DC Supply Current
VBIAS Shutdown RUN = 0V 1.1 µA Current VBIAS Sleep Mode SENSE+ < 3.2V, EXTV Current CC = 0V 15 µA Sleep Mode Current
2
VBIAS Current SENSE+ ≥ 3.2V, EXTVCC = 0V 5 µA VBIAS Current SENSE+ ≥ 3.2V, EXTVCC ≥ 4.8V 1 µA EXTVCC Current SENSE+ ≥ 3.2V, EXTVCC ≥ 4.8V 6 µA SENSE+ Current SENSE+ ≥ 3.2V 10 µA Pulse-Skipping (PS) or Forced Continuous Mode (FCM), V 2 mA BIAS or EXTVCC Current
2 Gate Drivers
DRVSET = INTV TGx or BGx On CC 1.0 Ω Resistance Pull-Up Pull-Down 1.0 Ω BOOST to DRVCC DRVSET = INTV Switch On Resistance CC 6 Ω TGx or BGx Rise Time 25 ns Transition Time
3
Fall Time 15 ns BGx Off to TGx On DTCA = 0V 15 ns Adaptive Delay Time
4
TGx Off to BGx On DTCB = 0V 15 ns Adaptive Delay Time
4
BGx Off to TGx On DTCA = 10kΩ 7 ns Open-Loop Delay
4
DTCA = 50kΩ 25 ns DTCA = 100kΩ 40 ns
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Rev. 0 5 of 48 Document Outline Features Applications General Description Typical Application TABLE OF CONTENTS Revision History Specifications Absolute Maximum Ratings Pin Configurations and Function Descriptions Typical Performance Characteristics Functional diagram Theory of Operation Main Control Loop Power and Bias Supplies (VBIAS, EXTVCC, DRVCC, and INTVCC) High-Side Bootstrap Capacitor Dead Time Control (DTCA and DTCB Pins) Startup and Shutdown (RUN and SS Pins) Light Load Operation: Burst Mode Operation, Pulse-Skipping, or Forced Continuous Mode (MODE Pin) Frequency Selection, Spread Spectrum, and Phase-Locked Loop (FREQ and PLLIN/SPREAD Pins) Output Overvoltage Protection Power Good Applications Information Inductor Value Calculation Inductor Core Selection Current Sense Selection Low Value Resistor Current Sensing Inductor DCR Current Sensing Setting the Operating Frequency Selecting the Light-Load Operating Mode Dead Time Control (DTCA and DTCB Pins) DTCx Pin Tied to Ground (Adaptive Dead Time Control) DTCx Pin connected with a resistor to GND Power FET Selection CIN and COUT Selection Setting the Output Voltage RUN Pin and Undervoltage Lockout Soft-Start (SS Pin) INTVCC Regulators (OPTI-DRIVE) Topside FET Driver Supply (CB) Minimum On-Time Considerations Fault Conditions: Overtemperature Protection Phase-Locked Loop and Frequency Synchronization Efficiency Considerations Checking Transient Response Design Example PCB Board Layout Checklist PCB Layout Debugging Typical Applications Related Parts Outline Dimensions Ordering Guide