Datasheet LTM4639 (Analog Devices)

LTM4639 Low VIN 20A DC/DC µModule Step-Down Regulator
FEATURES DESCRIPTION
n
Complete 20A Switch Mode Power Supply
The LTM®4639 is a complete 20A output high efficiency n
2.375V to 7V Input Voltage Range (VIN < 4.5V,
switch mode step-down DC/DC µModule (micromodule)
Need CPWR Bias)
regulator. Included in the package are the switching n
0.6V to 5.5V Output Voltage Range
controller, power FETs, inductor and compensation n
±1.5% Maximum Total DC Output Voltage Error
components. Operating over an input voltage range from
(–40°C to 125°C)
2.375V to 7V, the LTM4639 supports an output voltage n
Differential Remote Sense Amplifier for Precision
range of 0.6V to 5.5V, set by a single external resistor.
Regulation (VOUT ≤ 3.3V)
Only a few input and output capacitors are needed. n
Current Mode Control/Fast Transient Response
Current mode operation allows precision current sharing of n
Parallel Multiphase Current Sharing (Up to 80A)
up to four LTM4639 regulators to obtain up to 80A output. n
Frequency Synchronization
High switching frequency and a current mode architecture n Selectable Pulse-Skipping or Burst Mode® Operation enable a very fast transient response to line and load n Soft-Start/Voltage Tracking changes without sacrificing stability. The device supports n Up to 88% Efficiency (3.3VIN, 1.5VOUT) frequency synchronization, multiphase/current sharing, n Overcurrent Foldback Protection Burst Mode operation and output voltage tracking for n Output Overvoltage Protection supply rail sequencing. A diode-connected PNP transistor n Internal Temperature Monitor is included for use as an internal temperature monitor. For n Overtemperature Protection up to 20V input operation, please see the LTM4637. n 15mm × 15mm × 4.92mm BGA Package The LTM4639 is offered in a 15mm × 15mm × 4.92mm
APPLICATIONS
BGA package. The LTM4639 is RoHS compliant. L, LT, LTC, LTM, PolyPhase, Burst Mode, µModule, Linear Technology, the Linear logo are n Telecom Servers and Networking Equipment registered trademarks and LTpowerCAD is a trademark of Linear Technology Corporation. n All other trademarks are the property of their respective owners. Protected by U.S. Patents, Industrial Equipment including 5481178, 5847554, 6580258, 6304066, 6476589, 6774611, 6677210, 8163643. n Medical Systems n High Ambient Temperature Systems n 3.3V Input Systems
TYPICAL APPLICATION 3.3V to 1.5V Efficiency 3.3VIN, 1.5VOUT, 20A DC/DC µModule® Regulator and Power Loss
+5V BIAS 100 4.5 2.2µF 4.0 EFFICIENCY V 1µF 95 IN 3.5 3.3V 22µF 6.3V C 90 3.0 POWER LOSS COMPA VIN CPWR EXTVCC INTVCC PGOOD ×4 180pF VOUT COMPA V 2.5 OUT 1.5V 85 5k 0.1µF 20A COMPB V 2.0 OUT_LCL CFF* 100µF*+ TRACK/SS 680µF* DIFF_OUT 180pF 6.3V EFFICIENCY (%) 80 1.5 LTM4639 2.5V RUN ×2 ×2 CPWR = 5V V + OSNS FREQ = 400kHz POWER LOSS 1.0 fSET 75 V – 100k OSNS MODE_PLLIN 0.5 VFB TEMP+ 70 0 RFB** CBOT* 0 2 4 6 8 10 12 14 16 18 20 TEMP– SGND GND OT_TEST 40.2k 22pF OUTPUT CURRENT (A) * SEE TABLE 5 4639 TA01b ** SEE TABLE 1 4639 TA01a 4639f For more information www.linear.com/LTM4639 1