LTM4637IY#PBF Datasheet Summary

Product Information

• Part Number: LTM4637IY#PBF
• Manufacturer: Analog Devices
• Description: 20A DC/DC µModule Step-Down Regulator

Key Features

• Complete 20A Switch Mode Power Supply
• Input Voltage Range: 4.5V to 20V
• Output Voltage Range: 0.6V to 5.5V
• ±1.5% Total DC Output Voltage Error (-40°C to 125°C)
• Differential Remote Sense Amplifier for Precision Regulation for (VOUT ≤ 3.3V)
• Current Mode Control/Fast Transient Response
• Parallel Current Sharing (Up to 80A)
• Frequency Synchronization
• Selectable Pulse-Skipping or Burst Mode® Operation
• Soft-Start/Voltage Tracking
• Up to 88% Efficiency (12VIN, 1.8VOUT)
• Overcurrent Foldback Protection
• Output Overvoltage Protection
• Internal Temperature Monitor
• Overtemperature Protection
• 15mm × 15mm × 4.32mm LGA and 15mm × 15mm × 4.92mm BGA Packages
• SnPb (BGA) or RoHS Compliant (LGA and BGA) Finish

Applications

• Telecom Servers and Networking Equipment
• Industrial Equipment
• Medical Systems
• High Ambient Temperature Systems

Pin Configuration

• VIN: Power Input Pins
• INTVCC: Internal 5V LDO for Driving the Control Circuitry and the Power MOSFET Drivers
• MODE_PLLIN: Forced Continuous Mode, Burst Mode Operation, or Pulse-Skipping Mode Selection Pin and External Synchronization Input to Phase Detector Pin
• TRACK/SS: Output Voltage Tracking Pin and Soft-Start Inputs
• RUN: Run Control Pin
• COMP: Current Control Threshold and Error Amplifier Compensation Point
• MTP1-MTP7: Extra mounting pads used for increased solder integrity strength
• GND: Power Ground Pins for Both Input and Output
• fSET: A resistor can be applied from this pin to ground to set the operating frequency
• TEMP: Temperature Monitor
• EXTVCC: External power input to an internal control switch allows an external source greater than 4.7V, but less than 6V to supply IC power and bypass the internal INTVCC LDO
• PGOOD: Output Voltage Power Good Indicator
• VFB: The Negative Input of the Error Amplifier
• SGND: Signal Ground Pin
• VOUT: Power Output Pins
• VOSNS+: (+) Input to the Remote Sense Amplifier
• DIFF_OUT: Output of the Remote Sense Amplifier
• VOUT_LCL: This pin connects to VOUT through a 1M resistor, and to VFB with a 60.4k resistor
• VOSNS–: (–) Input to the Remote Sense Amplifier

Absolute Maximum Ratings

• VIN: -0.3V to 22V
• VOUT: -0.3V to 6V
• INTVCC, VOUT_LCL, PGOOD, EXTVCC: -0.3V to 6V
• MODE_PLLIN, fSET, TRACK/SS, VOSNS–, VOSNS+, DIFF_OUT: -0.3V to INTVCC
• VFB, COMP: -0.3V to 2.7V
• RUN: -0.3V to 5V
• TEMP: -0.3V to 0.8V
• INTVCC Peak Output Current: 100mA
• Internal Operating Temperature Range: -40°C to 125°C
• Storage Temperature Range: -55°C to 125°C
• Reflow (Peak Body) Temperature: 245°C

Order Information

• Part Number: LTM4637IY#PBF
• Pad or Ball Finish: SAC305 (RoHS)
• Part Marking: LTM4637Y
• Package Type: BGA
• MSL Rating: 4
• Temperature Range: -40°C to 125°C
• Device Finish Code: e1

Electrical Characteristics

• Input DC Voltage (VIN): 4.5V to 20V
• Output Voltage Range (VOUT): 0.6V to 5.5V
• Output Voltage, Total Variation with Line and Load: ±1.5% (1.477V to 1.523V at 1.5V output)
• RUN Pin On Threshold (VRUN): 1.1V to 1.4V
• RUN Pin On Hysteresis (VRUNHYS): 130mV
• Input Supply Bias Current (IQ(VIN)): 17mA to 54mA (depending on mode and conditions)
• Input Supply Current (IS(VIN)): 6.8A to 2.87A (depending on conditions)
• Output Continuous Current Range (IOUT(DC)): 0A to 20A
• Line Regulation Accuracy (ΔVOUT (Line)): 0.02% to 0.06% per volt
• Load Regulation Accuracy (ΔVOUT (Load)): 0.2% to 0.45%
• Output Ripple Voltage (VOUT(AC)): 30mVP-P
• Turn-On Overshoot (ΔVOUTLS): 15mV
• Turn-On Time (tSTART): 0.6ms
• Peak Deviation for Dynamic Load (ΔVOUTLS): 50mV
• Settling Time for Dynamic Load Step (tSETTLE): 50µs
• Output Current Limit (IOUTPK): 30A

Thermal Information

• LGA Package:TJ(MAX): 125°CθJA: 9.5°C/WθJCbottom: 4°C/WθJCtop: 6.7°C/WθJB: 4.5°C/W
• BGA Package:TJ(MAX): 125°CθJA: 10.4°C/WθJCbottom: 4.6°C/WθJCtop: 6.7°C/WθJB: 5.3°C/W

Package Information

• LGA Package: 15mm × 15mm × 4.32mm
• BGA Package: 15mm × 15mm × 4.92mm

Typical Performance Characteristics

• Efficiency vs Load Current: Various graphs showing efficiency at different input and output voltages
• Transient Response: Graphs showing transient response at different output voltages and load currents
• Turn-On No Load: Graph showing turn-on characteristics with no load
• Short-Circuit Protection: Graphs showing short-circuit protection characteristics

Applications Information

• Output Voltage Programming: The output voltage can be programmed using a single external resistor.
• Input Capacitors: Recommendations for input capacitors to handle RMS input ripple current.
• Output Capacitors: Recommendations for output capacitors to optimize transient performance.
• Burst Mode Operation: Information on enabling and operating in Burst Mode for improved efficiency at light loads.
• Pulse-Skipping Mode Operation: Information on enabling and operating in Pulse-Skipping Mode for reduced switching loss at intermediate currents.
• Forced Continuous Operation: Information on enabling forced continuous operation for fixed frequency and low output ripple.
• Multiphase Operation: Information on paralleling multiple LTM4637 devices for higher output current and reduced input/output ripple.
• PLL, Frequency Adjustment and Synchronization: Information on setting the switching frequency and synchronizing the device to an external clock.
• Output Voltage Tracking: Information on programming output voltage tracking using the TRACK/SS pin.
• Overcurrent and Overvoltage Protection: Information on the device's overcurrent and overvoltage protection features.
• Temperature Monitoring: Information on using the TEMP pin for internal temperature monitoring.
• Overtemperature Protection: Information on the device's overtemperature protection feature.
• Run Enable: Information on using the RUN pin to enable or disable the regulator.
• INTVCC Regulator: Information on the internal low dropout regulator.
• Stability Compensation: Information on internal compensation and using LTpowerCAD for stability analysis.
• Thermal Considerations and Output Current Derating: Information on thermal performance and derating curves.
• Safety Considerations: Information on safety