Datasheet LTC3633 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Dual Channel 3A, 15V Monolithic Synchronous Step-Down Regulator |
| Pages / Page | 28 / 1 — FEATURES. DESCRIPTION. 3.6V to 15V Input Voltage Range. 3A Output Current … |
| File Format / Size | PDF / 411 Kb |
| Document Language | English |
FEATURES. DESCRIPTION. 3.6V to 15V Input Voltage Range. 3A Output Current per Channel. Up to 95% Efficiency
Model Line for this Datasheet
Text Version of Document
LTC3633 Dual Channel 3A, 15V Monolithic Synchronous Step-Down Regulator
FEATURES DESCRIPTION
n
3.6V to 15V Input Voltage Range
The LTC®3633 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, n
Selectable 0°/180° Phase Shift Between Channels
which relaxes the requirements for input and output ca- n
Adjustable Switching Frequency: 500kHz to 4MHz
pacitance. The operating supply voltage range is from 3.6V n
External Frequency Synchronization
to 15V, making it suitable for dual cell lithium-ion batteries n
Current Mode Operation for Excellent Line and
as well as point of load power supply applications from
Load Transient Response
a 12V or 5V supply. n 0.6V Reference Allows Low Output Voltages The operating frequency is programmable and synchroniz- n User Selectable Burst Mode® Operation or Forced able from 500kHz to 4MHz with an external resistor. The Continuous Operation high frequency capability allows the use of small surface n Output Voltage Tracking and Soft-Start Capability mount inductors and capacitors. The unique constant n Short-Circuit Protected frequency/controlled on-time architecture is ideal for high n Overvoltage Input and Overtemperature Protection step-down ratio applications that operate at high frequency n Low Power 2.5V Linear Regulator Output while demanding fast transient response. An internal phase n Power Good Status Outputs lock loop servos the on-time of the internal one-shot timer n Available in (4mm × 5mm) QFN-28 and 28-Lead to match the frequency of the internal clock or an applied TSSOP Packages external clock. The LTC3633 can select between forced continuous mode
APPLICATIONS
and high efficiency Burst Mode operation. n Distributed Power Systems L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks n of Linear Technology Corporation. All other trademarks are the property of their respective Battery Powered Instruments owners. Protected by U.S. Patents including 5481178, 5847554, 6580258, 6304066, 6476589, n Point of Load Power Supplies 6774611.
TYPICAL APPLICATION
VIN
Efficiency vs Load Current
12V 47µF V V 100 100 RUN1 IN2 IN1 INTV Burst Mode x2 CC 90 OPERATION RUN2 ITH1 2.2µF ITH2 80 10 LTC3633 RT POWER LOSS (W) 70 MODE/SYNC 60 1 PHMODE 50 V2P5 TRACKSS2 TRACKSS1 40 0.1 EFFICIENCY (%) PGOOD2 PGOOD1 30 BOOST2 BOOST1 20 0.01 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 0.001 1 10 100 1000 10000 VFB2 VFB1 SGND PGND LOAD CURRENT (mA) 73.2k 45.3k 10k 10k 3633 TA01b 22µF 22µF 3633 TA01a 3633fd For more information www.linear.com/LTC3633 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
FEATURES DESCRIPTION
n
3.6V to 15V Input Voltage Range
The LTC®3633 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, n
Selectable 0°/180° Phase Shift Between Channels
which relaxes the requirements for input and output ca- n
Adjustable Switching Frequency: 500kHz to 4MHz
pacitance. The operating supply voltage range is from 3.6V n
External Frequency Synchronization
to 15V, making it suitable for dual cell lithium-ion batteries n
Current Mode Operation for Excellent Line and
as well as point of load power supply applications from
Load Transient Response
a 12V or 5V supply. n 0.6V Reference Allows Low Output Voltages The operating frequency is programmable and synchroniz- n User Selectable Burst Mode® Operation or Forced able from 500kHz to 4MHz with an external resistor. The Continuous Operation high frequency capability allows the use of small surface n Output Voltage Tracking and Soft-Start Capability mount inductors and capacitors. The unique constant n Short-Circuit Protected frequency/controlled on-time architecture is ideal for high n Overvoltage Input and Overtemperature Protection step-down ratio applications that operate at high frequency n Low Power 2.5V Linear Regulator Output while demanding fast transient response. An internal phase n Power Good Status Outputs lock loop servos the on-time of the internal one-shot timer n Available in (4mm × 5mm) QFN-28 and 28-Lead to match the frequency of the internal clock or an applied TSSOP Packages external clock. The LTC3633 can select between forced continuous mode
APPLICATIONS
and high efficiency Burst Mode operation. n Distributed Power Systems L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks n of Linear Technology Corporation. All other trademarks are the property of their respective Battery Powered Instruments owners. Protected by U.S. Patents including 5481178, 5847554, 6580258, 6304066, 6476589, n Point of Load Power Supplies 6774611.
TYPICAL APPLICATION
VIN
Efficiency vs Load Current
12V 47µF V V 100 100 RUN1 IN2 IN1 INTV Burst Mode x2 CC 90 OPERATION RUN2 ITH1 2.2µF ITH2 80 10 LTC3633 RT POWER LOSS (W) 70 MODE/SYNC 60 1 PHMODE 50 V2P5 TRACKSS2 TRACKSS1 40 0.1 EFFICIENCY (%) PGOOD2 PGOOD1 30 BOOST2 BOOST1 20 0.01 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 0.001 1 10 100 1000 10000 VFB2 VFB1 SGND PGND LOAD CURRENT (mA) 73.2k 45.3k 10k 10k 3633 TA01b 22µF 22µF 3633 TA01a 3633fd For more information www.linear.com/LTC3633 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
