Datasheet LTC7893 (Analog Devices)
| Hersteller | Analog Devices |
| Beschreibung | 100V Low IQ, Synchronous Boost Controller for GaN FETs in 28-Lead QFN (4mm x 5mm, Plastic Side Wettable) package |
| Seiten / Seite | 48 / 1 — Data Sheet. LTC7893. FEATURES. GENERAL DESCRIPTION. APPLICATIONS. TYPICAL … |
| Dateiformat / Größe | PDF / 1.5 Mb |
| Dokumentensprache | Englisch |
Data Sheet. LTC7893. FEATURES. GENERAL DESCRIPTION. APPLICATIONS. TYPICAL APPLICATION. VIN. 100. 8V TO 36V. 10µF ×4. RUN. VBIAS. SENSE+. ITH. 10nF
Modelllinie für dieses Datenblatt
Textversion des Dokuments
link to page 1
Data Sheet LTC7893
100V Low I , Synchronous Boost Controller for GaN FETs Q
FEATURES GENERAL DESCRIPTION
GaN Drive Technology Fully Optimized for GaN FETs The LTC®7893 is a high performance, step-up, dc-to-dc Output Voltage Up to 100V switching regulator controller that drives all N-channel Wide V synchronous gallium nitride (GaN) field effect transistor IN Range: 4V to 60V and Operates Down to 1V after Start-Up (FET) power stages from output voltages up to 100V. The LTC7893 solves many of the challenges traditionally No Catch, Clamp, or Bootstrap Diodes Needed faced when using GaN FETs. The LTC7893 simplifies the Internal Smart Bootstrap Switches Prevent application design while requiring no protection diodes Overcharging of High-Side Driver Supply and no other additional external components compared Resistor-Adjustable Dead Times to a silicon metal-oxide semiconductor field effect Split-Output Gate Drivers for Adjustable Turn On transistor (MOSFET) solution. and Turn Off Driver Strengths Accurate Adjustable Driver Voltage and UVLO The internal smart bootstrap switches prevent overcharging of the BOOST pin to the SW pin high-side Low Operating IQ: 15μA driver supply during dead times, protecting the gate of Programmable Frequency (100kHz to 3MHz) the top GaN FET. The dead times of the LTC7893 can Synchronizable Frequency (100kHz to 3MHz) optionally be optimized with external resistors for Spread Spectrum Frequency Modulation margin or to tailor the application for higher efficiency 28-Lead (4mm × 5mm), Side Wettable, QFN Package and allowing for high frequency operation. AEC-Q100 Qualified for Automotive Applications The gate drive voltage of the LTC7893 can be precisely
APPLICATIONS
adjusted from 4V to 5.5V to optimize performance, and to allow the use of different GaN FETs, or even logic level Automotive and Industrial Power Systems MOSFETs. When biased from the boost converter Military Avionics and Medical Systems regulator output, the LTC7893 can operate from an Telecommunications Power Systems input supply as low as 1V after start-up.
TYPICAL APPLICATION VIN 100 8V TO 36V 10µF ×4 RUN VBIAS SENSE+ ITH 10nF 2mΩ SS 1Ω SENSE– 95 INTVCC ILIM LTC7893 PGOOD ) EXTV (% CC 10kΩ Y PLLIN/SPREAD BOOST L 24.9kΩ 3.1µH C DTCA 0.1µF 90 10kΩ VOUT EN SW I DTCB 48V C 220pF 0.1µF 73.2kΩ 2.2Ω UP TO I F FREQ BGUP 18A + 1Ω VPRG EF BGDN 100µF fSW: 500kHz ×4 V 22nF 1Ω IN = 8V DRVSET TGUP 85 1Ω 475k V DRVUV IN = 12V TGDN MODE V V IN = 24V FB INTV DRV V CC CC GND 12.1k IN = 36V INTVCC VOUT = 48V 80 4.7µF 0.001 0.01 0.1 1 10 20 LOAD CURRENT (A)
001 002
Figure 1. High Efficiency, 48VOUT Output Boost Regulator Figure 2. VOUT Efficiency and Power Loss for Figure 1 Driving GaN FETs
Rev. 0
DOCUMENT FEEDBACK TECHNICAL SUPPORT
One Analog Wa y, Wilmington, MA 01887 -2356, U.S.A. Tel: 781.329.47 00 ©2024 Analog Devices, Inc. Al l rights rese rve d. 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
Data Sheet LTC7893
100V Low I , Synchronous Boost Controller for GaN FETs Q
FEATURES GENERAL DESCRIPTION
GaN Drive Technology Fully Optimized for GaN FETs The LTC®7893 is a high performance, step-up, dc-to-dc Output Voltage Up to 100V switching regulator controller that drives all N-channel Wide V synchronous gallium nitride (GaN) field effect transistor IN Range: 4V to 60V and Operates Down to 1V after Start-Up (FET) power stages from output voltages up to 100V. The LTC7893 solves many of the challenges traditionally No Catch, Clamp, or Bootstrap Diodes Needed faced when using GaN FETs. The LTC7893 simplifies the Internal Smart Bootstrap Switches Prevent application design while requiring no protection diodes Overcharging of High-Side Driver Supply and no other additional external components compared Resistor-Adjustable Dead Times to a silicon metal-oxide semiconductor field effect Split-Output Gate Drivers for Adjustable Turn On transistor (MOSFET) solution. and Turn Off Driver Strengths Accurate Adjustable Driver Voltage and UVLO The internal smart bootstrap switches prevent overcharging of the BOOST pin to the SW pin high-side Low Operating IQ: 15μA driver supply during dead times, protecting the gate of Programmable Frequency (100kHz to 3MHz) the top GaN FET. The dead times of the LTC7893 can Synchronizable Frequency (100kHz to 3MHz) optionally be optimized with external resistors for Spread Spectrum Frequency Modulation margin or to tailor the application for higher efficiency 28-Lead (4mm × 5mm), Side Wettable, QFN Package and allowing for high frequency operation. AEC-Q100 Qualified for Automotive Applications The gate drive voltage of the LTC7893 can be precisely
APPLICATIONS
adjusted from 4V to 5.5V to optimize performance, and to allow the use of different GaN FETs, or even logic level Automotive and Industrial Power Systems MOSFETs. When biased from the boost converter Military Avionics and Medical Systems regulator output, the LTC7893 can operate from an Telecommunications Power Systems input supply as low as 1V after start-up.
TYPICAL APPLICATION VIN 100 8V TO 36V 10µF ×4 RUN VBIAS SENSE+ ITH 10nF 2mΩ SS 1Ω SENSE– 95 INTVCC ILIM LTC7893 PGOOD ) EXTV (% CC 10kΩ Y PLLIN/SPREAD BOOST L 24.9kΩ 3.1µH C DTCA 0.1µF 90 10kΩ VOUT EN SW I DTCB 48V C 220pF 0.1µF 73.2kΩ 2.2Ω UP TO I F FREQ BGUP 18A + 1Ω VPRG EF BGDN 100µF fSW: 500kHz ×4 V 22nF 1Ω IN = 8V DRVSET TGUP 85 1Ω 475k V DRVUV IN = 12V TGDN MODE V V IN = 24V FB INTV DRV V CC CC GND 12.1k IN = 36V INTVCC VOUT = 48V 80 4.7µF 0.001 0.01 0.1 1 10 20 LOAD CURRENT (A)
001 002
Figure 1. High Efficiency, 48VOUT Output Boost Regulator Figure 2. VOUT Efficiency and Power Loss for Figure 1 Driving GaN FETs
Rev. 0
DOCUMENT FEEDBACK TECHNICAL SUPPORT
One Analog Wa y, Wilmington, MA 01887 -2356, U.S.A. Tel: 781.329.47 00 ©2024 Analog Devices, Inc. Al l rights rese rve d. 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