Datasheet LTC3119 (Analog Devices)

LTC3119 18V, 5A Synchronous Buck-Boost DC/DC Converter
FeaTures DescripTion
n
Input Voltage Range: 2.5V to 18V
The LTC®3119 is a high efficiency 18V monolithic buck- n
Runs Down to VIN = 250mV After Start-Up
boost converter that can deliver up to 5A of continuous n
Output Voltage Range: 0.8V to 18V
output current. Extensive feature integration and very n
5A Output Current in Buck Mode, VIN > 6V
low resistance internal power switches minimize the total n
3A Output Current for VIN = 3.6V, VOUT = 5V
solution footprint for even the most demanding applica- n Programmable Switching Frequency: 400kHz to 2MHz tions. A proprietary 4-switch PWM architecture provides n Synchronizable with an External Clock Up to 2MHz seamless low noise operation from input voltages above, n Accurate Run Comparator Threshold equal to, or below the output voltage. n Burst Mode® Operation, No-Load IQ = 35µA External frequency programming as well as synchroniza- n Ultralow Noise Buck-Boost PWM tion using an internal PLL enable operation over a wide n Current Mode Control switching frequency range of 400kHz to 2MHz. The wide n Maximum Power Point Control 2.5V to 18V input range is well suited for operation from n Power Good Indicator unregulated power sources including battery stacks and n Internal Soft-Start backup capacitors. After start-up, operation is possible n 28-Lead 4mm × 5mm QFN and TSSOP Packages with input voltages as low as 250mV. Other features include: output short-circuit protection,
applicaTions
thermal overload protection, less than 3µA shutdown n Wide Input Range Power Supplies current, power good indicator, Burst Mode operation, and n 1- to 4-Cell Lithium Battery Powered Products maximum power point control. n RF Power Supplies The LTC3119 is offered in thermally enhanced 28-lead n Solar Battery Chargers 4mm × 5mm QFN and TSSOP packages. n System Backup Power Supplies n Lead Acid to 12V Regulator L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks and PowerPath and No RSENSE are trademarks of Analog Devices, Inc. All other trademarks are the property of their respective owners.
Typical applicaTion Wide Input Range 5V Regulator Efficiency Efficiency
3.3µH 100 Burst Mode OPERATION 90 0.1µF 0.1µF SW1 SW2 80 BST1 BST2 VOUT VIN 70 PV 5V AT 5A, VIN > 6V IN PVOUT 2.5V TO 18V 5V AT 3A, VIN = 3.6V 60 10µF 100k VIN 150µF LTC3119 RUN 536k PWM 50 BURST PWM PWM/SYNC FB EFFICIENCY (%) 40 MPPC VCC PGOOD 30 SV V CC IN = 3V VC 102k RT 20 V PGND GND IN = 5V 4.7µF 78.7k VIN = 9V 105k 3119 TA01a 10 680pF 100μ 1m 10m 100m 1 10 LOAD CURRENT (A) 3119 TA01b 3119fb For more information www.linear.com/LTC3119 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Introduction PWM Mode Operation VCC Regulator Current Mode Control Error Amplifiers Current Limit and Zero Current Detection Soft-Start Maximum Power Point Control (MPPC) Burst Mode Operation Power Good Indicator Thermal Considerations Applications Information Typical Applications Package Description Revision History Typical Application Related Parts