Datasheet LTC7810 (Analog Devices) - 9

LTC7810
TYPICAL PERFORMANCE CHARACTERISTICS EXTVCC Switchover Thresholds DRVCC Load Regulation vs Temperature DRVCC Voltage vs Temperature
6.5 9.5 11 VIN = 12V NDRV LDO, DRVSET = INTVCC EXTVCC = 0V 8.9 RISING DRVSET OPEN DRVSET OPEN 10 6.0 8.3 FALLING 7.7 RISING 9 EXTV 5.5 CC or TAGE V 7.1 IN LDO, FALLING NDRV LDO TAGE (V) DRVSET = 0V EXTVCC = 0V EXTV VOL CC = 8.5V DRVSET = 0V 6.5 8 CC VOL 5.0 5.9 CC DRV 5.3 7 DRVSET = INTVCC DRV V RISING IN LDO 4.5 SWITCHOVER THRESHOLD (V) 4.7 6 EXTVCC = 5V FALLING 4.1 DRVSET = INTVCC 4.0 3.5 5 0 20 40 60 80 100 –55 –25 5 35 65 95 125 155 –55 –25 5 35 65 95 125 155 DRVCC LOAD CURRENT (mA) TEMPERATURE (°C) TEMPERATURE (°C) 7810 G19 7810 G20 7810 G21
Shutdown Current vs Temperature Shutdown Current vs VIN Voltage Quiescent Current vs Temperature
7.0 2.5 80 VIN = 12V 6.0 70 BURST MODE OPERATION 2.0 60 5.0 50 4.0 1.5 40 3.0 1.0 30 2.0 SHUTDOWN CURRENT (µA) SHUTDOWN CURRENT (µA) 20 0.5 QUIESCENT CURRENT (µA) 1.0 10 0 0 0 –55 –25 5 35 65 95 125 155 0 30 60 90 120 150 –55 –25 5 35 65 95 125 155 TEMPERATURE (°C) VIN VOLTAGE (V) TEMPERATURE (°C) 7810 G22 7810 G23 7810 G24
RUN and OVLO Thresholds DRVCC Undervoltage Lockout TRACK/SS Pull-Up Current vs Temperature Thresholds vs Temperature vs Temperature
1.35 8.0 10.3 RUN OR OVLO RISING RISING RUN FALLING 7.5 1.30 OVLO FALLING 10.2 7.0 FALLING DRVSET OPEN 1.25 TAGE (V) 6.5 10.1 1.20 6.0 DRVSET = 0V RISING 5.5 10.0 1.15 5.0 FALLING 9.9 1.10 4.5 UVLO THRESHOLD (V) RISING TRACK/SS CURRENT (µA) RUN OR OVLO PIN VOL 4.0 1.05 FALLING 9.8 3.5 DRVSET = INTVCC 1.00 3.0 9.7 –55 –25 5 35 65 95 125 155 –55 –25 5 35 65 95 125 155 –55 –25 5 35 65 95 125 155 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 7810 G25 7810 G26 7810 G27 Rev. A For more information www.analog.com 9 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Main Control Loop Power and Bias Supplies (VIN, NDRV, EXTVCC, DRVCC, REGSD) Boost Supply and Dropout (BOOST and SW pins) Start-Up and Shutdown (RUN, TRACK/SS, OVLO 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) Applications Information Current Sense Selection Low Value Resistor Current Sensing Inductor DCR Sensing Setting the Operating Frequency Selecting the Light-Load Operating Mode Inductor Value Calculation Inductor Core Selection Power MOSFET Selection CIN and COUT Selection Setting the Output Voltage RUN Pins and Overvoltage/Undervoltage Lockout Tracking and Soft-Start (TRACK/SS1, TRACK/SS2 Pins) Single Output Two-Phase Operation DRVCC Regulators Topside MOSFET Driver Supply (CB, DB) Burst Clamp Programming Fault Conditions: Current Limit and Current Foldback Fault Conditions: Overvoltage Protection (Crowbar) Fault Conditions: Overtemperature Protection Phase-Locked Loop and Frequency Synchronization Minimum On-Time Considerations Efficiency Considerations Checking Transient Response Design Example PC Board Layout Checklist PC Board Layout Debugging Typical Applications Package Description Revision History Typical Application Related Parts