Datasheet LTM4637 (Analog Devices)

LTM4637 20A DC/DC µModule Step-Down Regulator
FeaTures DescripTion
n
Complete 20A Switch Mode Power Supply
The LTM®4637 is a complete 20A output high efficiency n
4.5V to 20V Input Voltage Range
switch mode step-down DC/DC µModule (micromodule) n
0.6V to 5.5V Output Voltage Range
regulator. Included in the package are the switching control- n
±1.5% Total DC Output Voltage Error
ler, power FETs, inductor and compensation components.
(–40°C to 125°C)
Operating over an input voltage range from 4.5V to 20V, n
Differential Remote Sense Amplifier for Precision
the LTM4637 supports an output voltage range of 0.6V
Regulation for (VOUT ≤ 3.3V)
to 5.5V, set by a single external resistor. Only a few input n
Current Mode Control/Fast Transient Response
and output capacitors are needed. n
Parallel Current Sharing (Up to 80A)
n Current mode operation allows precision current sharing
Frequency Synchronization
n of up to four LTM4637 regulators to obtain up to 80A Selectable Pulse-Skipping or Burst Mode® Operation n output. High switching frequency and a current mode Soft-Start/Voltage Tracking n architecture enable a very fast transient response to line Up to 88% Efficiency (12VIN, 1.8VOUT) n and load changes without sacrificing stability. The device Overcurrent Foldback Protection n Output Overvoltage Protection supports frequency synchronization, multiphase/current n Internal Temperature Monitor sharing, Burst Mode operation and output voltage tracking n Overtemperature Protection for supply rail sequencing. A diode-connected PNP transis- n 15mm × 15mm × 4.32mm LGA and tor is available for use as an internal temperature monitor. 15mm × 15mm × 4.92mm BGA Packages The LTM4637 is offered in 15mm × 15mm × 4.32mm LGA n SnPb (BGA) or RoHS Compliant (LGA and BGA) Finish and 15mm × 15mm × 4.92mm packages. The LTM4637 is available with SnPb (BGA) or RoHS compliant terminal
applicaTions
finish. The LTM4637 is pin compatible with the LTM4627, n Telecom Servers and Networking Equipment a 15A DC/DC µModule regulator. n Industrial Equipment L, LT, LTC, LTM, PolyPhase, Burst Mode, µModule, Linear Technology, the Linear logo are registered trademarks and LTpowerCAD is a trademark of Linear Technology Corporation. n Medical Systems All other trademarks are the property of their respective owners. Protected by U.S. Patents, n including 5481178, 5847554, 6580258, 6304066, 6476589, 6774611, 6677210, 8163643. High Ambient Temperature Systems
Typical applicaTion 12VIN, 1.2VOUT, 20A DC/DC µModule® Regulator 12VIN Efficiency vs Load Current
2.2µF 100 V 1.2VOUT IN 12V 250kHz 22µF 95 CCM 16V 10k VIN EXTVCC INTVCC PGOOD ×4 VOUT 90 0.1µF COMP VOUT 1.2V 20A TRACK/SS VOUT_LCL 100µF* 85 330pF + 470µF RUN DIFF_OUT LTM4637 6.3V 6.3V ×2 ×2 80 f + SET VOSNS EFFICIENCY (%) MODE_PLLIN V – 75 OSNS TEMP VFB 70 SGND GND RFB** 60.4k * SEE TABLE 5 65 4637 TA01a 0 2 4 6 8 10 12 14 16 18 20 ** SEE TABLE 1 OUTPUT CURRENT (A) 4637 TA01b 4637fc For more information www.linear.com/LTM4637 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Decoupling Requirements Operation Applications Information Typical Applications Package Description Package PHOTO Typical Application Related Parts Design Resources