Datasheet LTC7801 (Analog Devices)
| Fabricante | Analog Devices |
| Descripción | 150V Low IQ, Synchronous Step-Down DC/DC Controller |
| Páginas / Página | 38 / 1 — FEATURES. DESCRIPTION. Wide VIN Range: 4V to 140V (150V Abs Max). Wide … |
| Revisión | A |
| Formato / tamaño de archivo | PDF / 4.1 Mb |
| Idioma del documento | Inglés |
FEATURES. DESCRIPTION. Wide VIN Range: 4V to 140V (150V Abs Max). Wide Output Voltage Range: 0.8V to 60V
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LTC7801 150V Low IQ, Synchronous Step-Down DC/DC Controller
FEATURES DESCRIPTION
n
Wide VIN Range: 4V to 140V (150V Abs Max)
The LTC®7801 is a high performance step-down switching n
Wide Output Voltage Range: 0.8V to 60V
regulator DC/DC controller that drives an all N-channel n
Adjustable Gate Drive Level: 5V to 10V (OPTI-DRIVE)
synchronous power MOSFET stage that can operate from n
Low Operating IQ: 40μA (Shutdown = 10μA)
input voltages up to 140V. A constant frequency current n
100% Duty Cycle Operation
mode architecture allows a phase-lockable frequency of n
Integrated Bootstrap Diode
up to 850kHz. n Selectable Gate Drive UVLO Thresholds The gate drive voltage can be programmed from 5V n Onboard LDO or External NMOS LDO for DRVCC to 10V to allow the use of logic or standard-level FETs n EXTVCC LDO Powers Drivers from VOUT to maximize efficiency. An integrated switch in the top n Phase-Lockable Frequency (75kHz to 850kHz) gate driver eliminates the need for an external bootstrap n Programmable Fixed Frequency (50kHz to 900kHz) diode. An internal charge pump allows for 100% duty n Selectable Continuous, Pulse-Skipping or Low Ripple cycle operation. Burst Mode® Operation at Light Loads n Adjustable Burst Clamp The low 40μA no-load quiescent current extends operat- n Power Good Output Voltage Monitor ing run time in battery-powered systems. OPTI-LOOP® n Programmable Input Overvoltage Lockout compensation allows the transient response to be opti- n Small 24-Lead 4mm × 5mm QFN or TSSOP Packages mized over a wide range of output capacitance and ESR values. The LTC7801 features a precision 0.8V refer-
APPLICATIONS
ence and power good output indicator. The output volt- age can be programmed between 0.8V to 60V using n Automotive and Industrial Power Systems external resistors. n High Voltage Battery Operated Systems All registered trademarks and trademarks are the property of their respective owners. Protected n Telecommunications Power Systems by U.S. Patents including 5481178, 5705919, 5929620, 6144194, 6177787, 6580258.
TYPICAL APPLICATION High Efficiency High Voltage 12V Output Step-Down Regulator Efficiency and Power Loss vs Load Current
VIN 7V to 140V 100µF 100 10k VIN RUN NDRV TG 90 0.1µF *V EFFICIENCY OUT FOLLOWS VIN WHEN VIN < 12V DRV 80 CC BOOST 1k 4.7µF 33µH 6mΩ POWER LOSS (mW) VOUT 70 LTC7801 12V* SW 5A 60 INTVCC BG 150µF 50 V 100 0.1µF CPUMP_EN IN = 24V x3 POWER LOSS 40 VIN = 48V SENSE+ EFFICIENCY (%) ITH 30 1nF 10 SENSE– 10k SS 20 0.1µF EXTVCC 10 100pF FREQ 511k VFB 0 1 4.7nF 30.1k 0.0001 0.001 0.01 0.1 1 10 36.5k GND LOAD CURRENT (A) 7801 TA01b 7801 TA01a Rev. A Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
FEATURES DESCRIPTION
n
Wide VIN Range: 4V to 140V (150V Abs Max)
The LTC®7801 is a high performance step-down switching n
Wide Output Voltage Range: 0.8V to 60V
regulator DC/DC controller that drives an all N-channel n
Adjustable Gate Drive Level: 5V to 10V (OPTI-DRIVE)
synchronous power MOSFET stage that can operate from n
Low Operating IQ: 40μA (Shutdown = 10μA)
input voltages up to 140V. A constant frequency current n
100% Duty Cycle Operation
mode architecture allows a phase-lockable frequency of n
Integrated Bootstrap Diode
up to 850kHz. n Selectable Gate Drive UVLO Thresholds The gate drive voltage can be programmed from 5V n Onboard LDO or External NMOS LDO for DRVCC to 10V to allow the use of logic or standard-level FETs n EXTVCC LDO Powers Drivers from VOUT to maximize efficiency. An integrated switch in the top n Phase-Lockable Frequency (75kHz to 850kHz) gate driver eliminates the need for an external bootstrap n Programmable Fixed Frequency (50kHz to 900kHz) diode. An internal charge pump allows for 100% duty n Selectable Continuous, Pulse-Skipping or Low Ripple cycle operation. Burst Mode® Operation at Light Loads n Adjustable Burst Clamp The low 40μA no-load quiescent current extends operat- n Power Good Output Voltage Monitor ing run time in battery-powered systems. OPTI-LOOP® n Programmable Input Overvoltage Lockout compensation allows the transient response to be opti- n Small 24-Lead 4mm × 5mm QFN or TSSOP Packages mized over a wide range of output capacitance and ESR values. The LTC7801 features a precision 0.8V refer-
APPLICATIONS
ence and power good output indicator. The output volt- age can be programmed between 0.8V to 60V using n Automotive and Industrial Power Systems external resistors. n High Voltage Battery Operated Systems All registered trademarks and trademarks are the property of their respective owners. Protected n Telecommunications Power Systems by U.S. Patents including 5481178, 5705919, 5929620, 6144194, 6177787, 6580258.
TYPICAL APPLICATION High Efficiency High Voltage 12V Output Step-Down Regulator Efficiency and Power Loss vs Load Current
VIN 7V to 140V 100µF 100 10k VIN RUN NDRV TG 90 0.1µF *V EFFICIENCY OUT FOLLOWS VIN WHEN VIN < 12V DRV 80 CC BOOST 1k 4.7µF 33µH 6mΩ POWER LOSS (mW) VOUT 70 LTC7801 12V* SW 5A 60 INTVCC BG 150µF 50 V 100 0.1µF CPUMP_EN IN = 24V x3 POWER LOSS 40 VIN = 48V SENSE+ EFFICIENCY (%) ITH 30 1nF 10 SENSE– 10k SS 20 0.1µF EXTVCC 10 100pF FREQ 511k VFB 0 1 4.7nF 30.1k 0.0001 0.001 0.01 0.1 1 10 36.5k GND LOAD CURRENT (A) 7801 TA01b 7801 TA01a Rev. A Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts