Datasheet LTC3892, LTC3892-1, LTC3892-2 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 60V Low IQ, Dual, 2-Phase Synchronous Step-Down DC/DC Controller |
| Pages / Page | 38 / 1 — FEATURES. DESCRIPTION. Wide VIN Range: 4.5V to 60V (65V Abs Max). Wide … |
| File Format / Size | PDF / 1.4 Mb |
| Document Language | English |
FEATURES. DESCRIPTION. Wide VIN Range: 4.5V to 60V (65V Abs Max). Wide Output Voltage Range: 0.8V ≤ VOUT ≤ 99% • VIN
Model Line for this Datasheet
- LTC3892EFE-1#PBF LTC3892EFE-1#TRPBF LTC3892EUH#PBF LTC3892EUH#TRPBF LTC3892EUH-2#PBF LTC3892EUH-2#TRPBF LTC3892HFE-1#PBF LTC3892HFE-1#TRPBF LTC3892HUH#PBF LTC3892HUH#TRPBF LTC3892HUH-2#PBF LTC3892HUH-2#TRPBF LTC3892IFE-1#PBF LTC3892IFE-1#TRPBF LTC3892IUH#PBF LTC3892IUH#TRPBF LTC3892IUH-2#PBF LTC3892IUH-2#TRPBF LTC3892MPFE-1#PBF LTC3892MPFE-1#TRPBF LTC3892MPUH#PBF LTC3892MPUH#TRPBF LTC3892MPUH-2#PBF LTC3892MPUH-2#TRPBF
Text Version of Document
LTC3892/ LTC3892-1/LTC3892-2 60V Low IQ, Dual, 2-Phase Synchronous Step-Down DC/DC Controller
FEATURES DESCRIPTION
n
Wide VIN Range: 4.5V to 60V (65V Abs Max)
The LTC®3892/LTC3892-1/LTC3892-2 is a high perfor- n
Wide Output Voltage Range: 0.8V ≤ VOUT ≤ 99% • VIN
mance dual step-down DC/DC switching regulator control- n
Adjustable Gate Drive Level 5V to 10V (OPTI-DRIVE)
ler that drives all N-channel synchronous power MOSFET n
No External Bootstrap Diodes Required
stages. Power loss and noise are minimized by operating n
Low Operating IQ: 29μA (One Channel On)
the two controller output stages out-of-phase. n Selectable Gate Drive UVLO Thresholds The gate drive voltage can be programmed from 5V to n Out-of-Phase Operation Reduces Required Input 10V to allow the use of logic or standard-level FETs and Capacitance and Power Supply Induced Noise to maximize efficiency. Internal switches in the top gate n Phase-Lockable Frequency: 75kHz to 850kHz drivers eliminate the need for external bootstrap diodes. n Selectable Continuous, Pulse Skipping or Low Ripple Burst Mode® Operation at Light Loads A wide 4.5V to 60V input supply range encompasses a wide n Selectable Current Limit (LTC3892/LTC3892-2) range of intermediate bus voltages and battery chemistries. n Very Low Dropout Operation: 99% Duty Cycle Output voltages up to 99% of VIN can be regulated. OPTI- n Power Good Output Voltage Monitors (LTC3892/LTC3892-2) LOOP® compensation allows the transient response and n Low Shutdown I loop stability to be optimized over a wide range of output Q: 3.6μA n Small 32-Lead 5mm × 5mm QFN Package (LTC3892/ capacitance and ESR values. LTC3892-2) or TSSOP Package (LTC3892-1) The 29μA no-load quiescent current extends operating run time in battery powered systems. For a comparison of the
APPLICATIONS
LTC3892 to the LTC3892-1 and LTC3892-2, see Table 1 in the Pin Functions section of this data sheet. n Automotive and Industrial Power Systems L, LT, LTC, LTM, Burst Mode, OPTI-LOOP, Linear Technology and the Linear logo are n Distributed DC Power Systems registered trademarks of Analog Devices, Inc. All other trademarks are the property of their n respective owners. Protected by U.S. Patents including 5481178, 5705919, 5929620, 6144194, High Voltage Battery Operated Systems 6177787, 6580258.
TYPICAL APPLICATION High Efficiency Dual 5V/12V Output Step-Down Converter
VIN 12.5V TO 60V 47µF RUN1 VIN RUN2
Efficiency vs Output Current
TG1 TG2
Efficiency vs Output Current
96 0.1µF BOOST1 BOOST2 0.1µF V V IN = 12V OUT1 5mΩ 5.6µH 15µH 8mΩ VOUT2 5V 95 VOUT = 5V SW1 SW2 12V 8A 5A Burst Mode OPERATION 94 BG1 BG2 220µF 150µF LTC3892 93 SENSE1+ SENSE2+ 100k 92 1nF 1nF SENSE1– SENSE2– 91 GATE DRIVE EFFICIENCY (%) VFB1 VFB2 DRVCC=5V 90 ITH1 ITH2 DRVCC=6V DRV TRACK/SS1 TRACK/SS2 CC=8V 89 DRV 7.15k CC=10V VPRG1 DRVSET 88 7.5k 34.8k DRVUV 0.01 0.1 1 10 100pF 0.1µF 0.1µF 100pF LOAD CURRENT (A) INTVCC GND DRVCC 3892 F01b 2.2nF 1nF 0.1µF 4.7µF 3892 TA01 38921fc For more information www.linear.com/LTC3892 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Typical Performance Characteristics Pin Functions Functional Diagrams Operation Package Description Typical Application Related Parts
FEATURES DESCRIPTION
n
Wide VIN Range: 4.5V to 60V (65V Abs Max)
The LTC®3892/LTC3892-1/LTC3892-2 is a high perfor- n
Wide Output Voltage Range: 0.8V ≤ VOUT ≤ 99% • VIN
mance dual step-down DC/DC switching regulator control- n
Adjustable Gate Drive Level 5V to 10V (OPTI-DRIVE)
ler that drives all N-channel synchronous power MOSFET n
No External Bootstrap Diodes Required
stages. Power loss and noise are minimized by operating n
Low Operating IQ: 29μA (One Channel On)
the two controller output stages out-of-phase. n Selectable Gate Drive UVLO Thresholds The gate drive voltage can be programmed from 5V to n Out-of-Phase Operation Reduces Required Input 10V to allow the use of logic or standard-level FETs and Capacitance and Power Supply Induced Noise to maximize efficiency. Internal switches in the top gate n Phase-Lockable Frequency: 75kHz to 850kHz drivers eliminate the need for external bootstrap diodes. n Selectable Continuous, Pulse Skipping or Low Ripple Burst Mode® Operation at Light Loads A wide 4.5V to 60V input supply range encompasses a wide n Selectable Current Limit (LTC3892/LTC3892-2) range of intermediate bus voltages and battery chemistries. n Very Low Dropout Operation: 99% Duty Cycle Output voltages up to 99% of VIN can be regulated. OPTI- n Power Good Output Voltage Monitors (LTC3892/LTC3892-2) LOOP® compensation allows the transient response and n Low Shutdown I loop stability to be optimized over a wide range of output Q: 3.6μA n Small 32-Lead 5mm × 5mm QFN Package (LTC3892/ capacitance and ESR values. LTC3892-2) or TSSOP Package (LTC3892-1) The 29μA no-load quiescent current extends operating run time in battery powered systems. For a comparison of the
APPLICATIONS
LTC3892 to the LTC3892-1 and LTC3892-2, see Table 1 in the Pin Functions section of this data sheet. n Automotive and Industrial Power Systems L, LT, LTC, LTM, Burst Mode, OPTI-LOOP, Linear Technology and the Linear logo are n Distributed DC Power Systems registered trademarks of Analog Devices, Inc. All other trademarks are the property of their n respective owners. Protected by U.S. Patents including 5481178, 5705919, 5929620, 6144194, High Voltage Battery Operated Systems 6177787, 6580258.
TYPICAL APPLICATION High Efficiency Dual 5V/12V Output Step-Down Converter
VIN 12.5V TO 60V 47µF RUN1 VIN RUN2
Efficiency vs Output Current
TG1 TG2
Efficiency vs Output Current
96 0.1µF BOOST1 BOOST2 0.1µF V V IN = 12V OUT1 5mΩ 5.6µH 15µH 8mΩ VOUT2 5V 95 VOUT = 5V SW1 SW2 12V 8A 5A Burst Mode OPERATION 94 BG1 BG2 220µF 150µF LTC3892 93 SENSE1+ SENSE2+ 100k 92 1nF 1nF SENSE1– SENSE2– 91 GATE DRIVE EFFICIENCY (%) VFB1 VFB2 DRVCC=5V 90 ITH1 ITH2 DRVCC=6V DRV TRACK/SS1 TRACK/SS2 CC=8V 89 DRV 7.15k CC=10V VPRG1 DRVSET 88 7.5k 34.8k DRVUV 0.01 0.1 1 10 100pF 0.1µF 0.1µF 100pF LOAD CURRENT (A) INTVCC GND DRVCC 3892 F01b 2.2nF 1nF 0.1µF 4.7µF 3892 TA01 38921fc For more information www.linear.com/LTC3892 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Typical Performance Characteristics Pin Functions Functional Diagrams Operation Package Description Typical Application Related Parts
