Datasheet LTC3633A-2, LTC3633A-3 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Dual Channel 3A, 20V Monolithic Synchronous Step-Down Regulator |
| Pages / Page | 28 / 1 — FEATURES. DESCRIPTION. 3.6V to 20V Input Voltage Range. 3A Output Current … |
| File Format / Size | PDF / 424 Kb |
| Document Language | English |
FEATURES. DESCRIPTION. 3.6V to 20V Input Voltage Range. 3A Output Current per Channel. Up to 95% Efficiency
Model Line for this Datasheet
- LTC3633AEFE-2#PBF LTC3633AEFE-2#TRPBF LTC3633AEFE-3#PBF LTC3633AEFE-3#TRPBF LTC3633AEUFD-2#PBF LTC3633AEUFD-2#TRPBF LTC3633AEUFD-3#PBF LTC3633AEUFD-3#TRPBF LTC3633AIFE-2#PBF LTC3633AIFE-2#TRPBF LTC3633AIFE-3#PBF LTC3633AIFE-3#TRPBF LTC3633AIUFD-2#PBF LTC3633AIUFD-2#TRPBF LTC3633AIUFD-3#PBF LTC3633AIUFD-3#TRPBF
Text Version of Document
LTC3633A-2/LTC3633A-3 Dual Channel 3A, 20V Monolithic Synchronous Step-Down Regulator
FEATURES DESCRIPTION
n
3.6V to 20V Input Voltage Range
The LTC®3633A-2 is a high efficiency, dual-channel mono- n
3A Output Current per Channel
lithic synchronous buck regulator using a controlled on-time, n
Up to 95% Efficiency
current mode architecture, with phase lockable switching n
Low Duty Cycle Operation: 5% at 2.25MHz
frequency. The two channels can run 180° out of phase to n
Selectable 0°/180° Phase Shift Between Channels
relax the requirements for input and output capacitance. The n
Adjustable Switching Frequency: 500kHz to 4MHz
operating supply voltage range is from 3.6V to 20V, making n
External Frequency Synchronization
it suitable for lithium-ion battery stacks as well as point of n
Current Mode Operation for Excellent Line and
load power supply applications from a 12V or 5V supply.
Load Transient Response
The operating frequency is programmable from 500kHz to n 0.6V Reference Allows Low Output Voltages 4MHz with an external resistor and may be synchronized n User Selectable Burst Mode® Operation or Forced Continuous Operation to an external clock signal. The high frequency capabil- ity allows the use of small surface mount inductors and n Output Voltage Tracking and Soft-Start Capability capacitors. The unique constant frequency/controlled on- n Short-Circuit Protected time architecture is ideal for high step-down ratio applica- n Overvoltage Input and Overtemperature Protection tions that operate at high frequency while demanding fast n Power Good Status Outputs transient response. An internal phase locked loop servos n Available in (4mm × 5mm) QFN-28 and 28-Lead TSSOP Packages the on-time of the internal one-shot timer to match the frequency of the internal clock or an applied external clock.
APPLICATIONS
The LTC3633A-2 can select between forced continuous n mode and high efficiency Burst Mode operation. The Distributed Power Systems n LTC3633A-2 and LTC3633A-3 differ in their output volt- Battery Powered Instruments n age sense range (refer to Table 1 in the Operation section Point of Load Power Supplies L for a description of the entire LTC3633A product family). , LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5481178, 5847554, 6580258, 6304066, 6476589, 6774611.
TYPICAL APPLICATION Efficiency vs Load Current
VIN 6V TO 20V 100 47µF PVIN2 PVIN1 SVIN Burst Mode x2 90 OPERATION RUN1 INTVCC 80 RUN2 ITH1 2.2µF LTC3633A-2 ITH2 70 RT 60 MODE/SYNC 50 PHMODE 40 TRACKSS2 TRACKSS1 EFFICIENCY (%) PGOOD2 PGOOD1 30 BOOST2 BOOST1 20 1.5µH 0.1µF 0.1µF 1µH VOUT2 SW2 SW1 VOUT1 10 VOUT = 5V 5V AT 3A 3.3V AT 3A VIN = 12V VOUT = 3.3V VON2 VON1 0 V V 0.001 0.01 0.1 1 10 FB2 FB1 73.2k SGND PGND 45.3k LOAD CURRENT (A) 22µF 10k 10k 22µF 3633a23 TA01b 3633a23 TA01a 3633a23fb For more information www.linear.com/LTC3633A-2 1 Document Outline Description Typical Application Absolute Maximum Ratings Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Operation Applications Information Package Description Typical Application Related Parts
FEATURES DESCRIPTION
n
3.6V to 20V Input Voltage Range
The LTC®3633A-2 is a high efficiency, dual-channel mono- n
3A Output Current per Channel
lithic synchronous buck regulator using a controlled on-time, n
Up to 95% Efficiency
current mode architecture, with phase lockable switching n
Low Duty Cycle Operation: 5% at 2.25MHz
frequency. The two channels can run 180° out of phase to n
Selectable 0°/180° Phase Shift Between Channels
relax the requirements for input and output capacitance. The n
Adjustable Switching Frequency: 500kHz to 4MHz
operating supply voltage range is from 3.6V to 20V, making n
External Frequency Synchronization
it suitable for lithium-ion battery stacks as well as point of n
Current Mode Operation for Excellent Line and
load power supply applications from a 12V or 5V supply.
Load Transient Response
The operating frequency is programmable from 500kHz to n 0.6V Reference Allows Low Output Voltages 4MHz with an external resistor and may be synchronized n User Selectable Burst Mode® Operation or Forced Continuous Operation to an external clock signal. The high frequency capabil- ity allows the use of small surface mount inductors and n Output Voltage Tracking and Soft-Start Capability capacitors. The unique constant frequency/controlled on- n Short-Circuit Protected time architecture is ideal for high step-down ratio applica- n Overvoltage Input and Overtemperature Protection tions that operate at high frequency while demanding fast n Power Good Status Outputs transient response. An internal phase locked loop servos n Available in (4mm × 5mm) QFN-28 and 28-Lead TSSOP Packages the on-time of the internal one-shot timer to match the frequency of the internal clock or an applied external clock.
APPLICATIONS
The LTC3633A-2 can select between forced continuous n mode and high efficiency Burst Mode operation. The Distributed Power Systems n LTC3633A-2 and LTC3633A-3 differ in their output volt- Battery Powered Instruments n age sense range (refer to Table 1 in the Operation section Point of Load Power Supplies L for a description of the entire LTC3633A product family). , LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5481178, 5847554, 6580258, 6304066, 6476589, 6774611.
TYPICAL APPLICATION Efficiency vs Load Current
VIN 6V TO 20V 100 47µF PVIN2 PVIN1 SVIN Burst Mode x2 90 OPERATION RUN1 INTVCC 80 RUN2 ITH1 2.2µF LTC3633A-2 ITH2 70 RT 60 MODE/SYNC 50 PHMODE 40 TRACKSS2 TRACKSS1 EFFICIENCY (%) PGOOD2 PGOOD1 30 BOOST2 BOOST1 20 1.5µH 0.1µF 0.1µF 1µH VOUT2 SW2 SW1 VOUT1 10 VOUT = 5V 5V AT 3A 3.3V AT 3A VIN = 12V VOUT = 3.3V VON2 VON1 0 V V 0.001 0.01 0.1 1 10 FB2 FB1 73.2k SGND PGND 45.3k LOAD CURRENT (A) 22µF 10k 10k 22µF 3633a23 TA01b 3633a23 TA01a 3633a23fb For more information www.linear.com/LTC3633A-2 1 Document Outline Description Typical Application Absolute Maximum Ratings Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Operation Applications Information Package Description Typical Application Related Parts
