Datasheet LTC3633A, LTC3633A-1 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Dual Channel 3A, 20V Monolithic Synchronous Step-Down Regulator |
| Pages / Page | 30 / 1 — FEATURES. DESCRIPTION. 3.6V to 20V Input Voltage Range. 3A Output Current … |
| File Format / Size | PDF / 417 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
Text Version of Document
LTC3633A/LTC3633A-1 Dual Channel 3A, 20V Monolithic Synchronous Step-Down Regulator
FEATURES DESCRIPTION
n
3.6V to 20V Input Voltage Range
The LTC®3633A is a high efficiency, dual-channel monolithic n
3A Output Current per Channel
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 Mode 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 LTC3633: 16V Absolute Maximum VIN the on-time of the internal one-shot timer to match the n LTC3633A: 20V Absolute Maximum VIN, Pin Compatible with LTC3633 frequency of the internal clock or an applied external clock. n Low Profile (4mm × 5mm) QFN-28 and 28-Lead The LTC3633A can select between forced continuous mode TSSOP Packages and high efficiency Burst Mode operation. The LTC3633A and LTC3633A-1 differ in their output voltage sense range
APPLICATIONS
(refer to Table 1 in the Operation section for a description n of the entire LTC3633A product family). Distributed Power Systems n Battery Powered Instruments L, 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 n Point of Load Power Supplies 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 V V Burst Mode RUN1 IN2 IN1 x2 INTVCC 90 OPERATION RUN2 ITH1 2.2µF 80 ITH2 LTC3633A 70 RT MODE/SYNC 60 PHMODE 50 V2P5 40 TRACKSS2 TRACKSS1 EFFICIENCY (%) 30 PGOOD2 PGOOD1 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 00.001 0.01 0.1 1 10 VFB2 VFB1 SGND PGND LOAD CURRENT (A) 73.2k 22µF 10k 45.3k 10k 22µF 3633a TA01b 3633a TA01a 3633a1fb For more information www.linear.com/LTC3633A 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 is a high efficiency, dual-channel monolithic n
3A Output Current per Channel
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 Mode 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 LTC3633: 16V Absolute Maximum VIN the on-time of the internal one-shot timer to match the n LTC3633A: 20V Absolute Maximum VIN, Pin Compatible with LTC3633 frequency of the internal clock or an applied external clock. n Low Profile (4mm × 5mm) QFN-28 and 28-Lead The LTC3633A can select between forced continuous mode TSSOP Packages and high efficiency Burst Mode operation. The LTC3633A and LTC3633A-1 differ in their output voltage sense range
APPLICATIONS
(refer to Table 1 in the Operation section for a description n of the entire LTC3633A product family). Distributed Power Systems n Battery Powered Instruments L, 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 n Point of Load Power Supplies 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 V V Burst Mode RUN1 IN2 IN1 x2 INTVCC 90 OPERATION RUN2 ITH1 2.2µF 80 ITH2 LTC3633A 70 RT MODE/SYNC 60 PHMODE 50 V2P5 40 TRACKSS2 TRACKSS1 EFFICIENCY (%) 30 PGOOD2 PGOOD1 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 00.001 0.01 0.1 1 10 VFB2 VFB1 SGND PGND LOAD CURRENT (A) 73.2k 22µF 10k 45.3k 10k 22µF 3633a TA01b 3633a TA01a 3633a1fb For more information www.linear.com/LTC3633A 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
