Datasheet LTC3895 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 150V Low IQ, Synchronous Step-Down DC/DC Controller |
| Pages / Page | 38 / 1 — FeaTures. DescripTion. Wide VIN Range: 4V to 140V (150V Abs Max). Wide … |
| File Format / Size | PDF / 2.3 Mb |
| Document Language | English |
FeaTures. DescripTion. Wide VIN Range: 4V to 140V (150V Abs Max). Wide Output Voltage Range: 0.8V to 60V
Model Line for this Datasheet
Text Version of Document
LTC3895 150V Low IQ, Synchronous Step-Down DC/DC Controller
FeaTures DescripTion
n
Wide VIN Range: 4V to 140V (150V Abs Max)
The LTC®3895 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
No External Bootstrap Diode Required
up to 850kHz. n Selectable Gate Drive UVLO Thresholds The gate drive voltage can be programmed from 5V to 10V n Onboard LDO or External NMOS LDO for DRVCC to allow the use of logic or standard-level FETs to maxi- n EXTVCC LDO Powers Drivers from VOUT mize efficiency. An integrated switch in the top gate driver n Phase-Lockable Frequency (75kHz to 850kHz) eliminates the need for an external bootstrap diode. An n Programmable Fixed Frequency (50kHz to 900kHz) internal charge pump allows for 100% duty cycle operation. n Selectable Continuous, Pulse-Skipping or Low Ripple Burst Mode® Operation at Light Loads The low 40μA no-load quiescent current extends operating n Adjustable Burst Clamp and Current Limit run time in battery-powered systems. OPTI-LOOP® com- n Adjustable or Fixed (5V/3.3V) Output Voltage pensation allows the transient response to be optimized n Power Good Output Voltage Monitor over a wide range of output capacitance and ESR values. n Programmable Input Overvoltage Lockout The LTC3895 features a precision 0.8V reference and n 38-Lead TSSOP High Voltage Package power good output indicator. The output voltage can be programmed between 0.8V to 60V using external resistors
applicaTions
or pin-programmed for a fixed 5V or 3.3V. L, LT, LTC, LTM, Burst Mode, OPTI-LOOP, PolyPhase, Linear Technology and the Linear logo n Automotive and Industrial Power Systems are registered trademarks of Linear Technology Corporation. All other trademarks are the n High Voltage Battery Operated Systems property of their respective owners. Protected by U.S. Patents including 5481178, 5705919, 5929620, 6144194, 6177787, 6580258. n Telecommunications Power Systems
Typical applicaTion High Efficiency High Voltage 12V Output Step-Down Regulator Efficiency and Power Loss
V
vs Load Current
IN 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 LTC3895 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) 3895 TA01b 3895fa For more information www.linear.com/LTC3895 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration 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®3895 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
No External Bootstrap Diode Required
up to 850kHz. n Selectable Gate Drive UVLO Thresholds The gate drive voltage can be programmed from 5V to 10V n Onboard LDO or External NMOS LDO for DRVCC to allow the use of logic or standard-level FETs to maxi- n EXTVCC LDO Powers Drivers from VOUT mize efficiency. An integrated switch in the top gate driver n Phase-Lockable Frequency (75kHz to 850kHz) eliminates the need for an external bootstrap diode. An n Programmable Fixed Frequency (50kHz to 900kHz) internal charge pump allows for 100% duty cycle operation. n Selectable Continuous, Pulse-Skipping or Low Ripple Burst Mode® Operation at Light Loads The low 40μA no-load quiescent current extends operating n Adjustable Burst Clamp and Current Limit run time in battery-powered systems. OPTI-LOOP® com- n Adjustable or Fixed (5V/3.3V) Output Voltage pensation allows the transient response to be optimized n Power Good Output Voltage Monitor over a wide range of output capacitance and ESR values. n Programmable Input Overvoltage Lockout The LTC3895 features a precision 0.8V reference and n 38-Lead TSSOP High Voltage Package power good output indicator. The output voltage can be programmed between 0.8V to 60V using external resistors
applicaTions
or pin-programmed for a fixed 5V or 3.3V. L, LT, LTC, LTM, Burst Mode, OPTI-LOOP, PolyPhase, Linear Technology and the Linear logo n Automotive and Industrial Power Systems are registered trademarks of Linear Technology Corporation. All other trademarks are the n High Voltage Battery Operated Systems property of their respective owners. Protected by U.S. Patents including 5481178, 5705919, 5929620, 6144194, 6177787, 6580258. n Telecommunications Power Systems
Typical applicaTion High Efficiency High Voltage 12V Output Step-Down Regulator Efficiency and Power Loss
V
vs Load Current
IN 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 LTC3895 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) 3895 TA01b 3895fa For more information www.linear.com/LTC3895 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
