4V to 36V, 3A Step-Down DC/DC Power Module in Compact 7x9x4mm QFN Package


Sample Availability

Prototype samples are available (PLMZM33603RLRR). Order Now


The LMZM33603 power module is an easy-to-use integrated power solution that combines a 3-A, step-down, DC-DC converter with power MOSFETs, a shielded inductor, and passives into a low-profile package. This power solution requires as few as four external components and eliminates the loop compensation and magnetics part selection from the design process.

The 9 mm × 7 mm × 4 mm, 18-pin, QFN package is easy to solder onto a printed circuit board and allows a compact, low-profile, point-of-load design. The full feature set, including power good, programmable UVLO, prebias start-up, and over-current / over-temperature protection, make the LMZM33603 ideal for powering a wide range of applications.


  • Complete Integrated Power Solution
    • As Few as 4 External Components
    • Minimum Solution Size < 100 mm2
  • 9 mm × 7 mm × 4 mm QFN Package
    • All Pins Accessible from Package Perimeter
    • Pin Compatiable with LMZM33602
  • 4-V to 36-V Input Voltage Range
  • Output Voltage Range
    • 1 V to 13.5 V at 3 A
    • 1 V to 18 V at 2 A
  • Efficiencies Up To 95%
  • Adjustable Switching Frequency
    (200 kHz to 1.2 MHz)
  • Allows Synchronization to an External Clock
  • Power-Good Output
  • Meets EN55011 Radiated EMI Standards
  • Operating IC Junction Range: –40°C to 125°C
  • Operating Ambient Temperature: –40°C to 105°C

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Parametrics Compare all products in Step-Down (Buck) Module

Iout (Max) (A)
Vin (Min) (V)
Vin (Max) (V)
Vout (Min) (V)
Vout (Max) (V)
Soft Start
Regulated Outputs (#)
Package Size: mm2:W x L (PKG)
Switching Frequency (Max) (kHz)
Switching Frequency (Min) (kHz)
Switching Frequency (Typ) (kHz)
Operating Temperature Range (C)
LMZM33603 LMZ34202 LMZ35003 LMZ36002
3    2    2.5    2   
4    4.5    7    4.5   
36    42    50    60   
1    2.5    2.5    2.5   
18    7.5    15    7.5   
Fixed    Adjustable    Adjustable    Adjustable   
EMI Tested
Frequency Synchronization
Power Good   
EMI Tested
Frequency Synchronization
Light Load Efficiency
Power Good
Remote Sense   
EMI Tested
Frequency Synchronization
Power Good
Remote Sense
EMI Tested
Frequency Synchronization
Light Load Efficiency
Power Good
Remote Sense   
1    1    1    1   
18B2QFN: 63 mm2: 7 x 9(B2QFN)    43B3QFN: 100 mm2: 10 x 10(B3QFN)    41B1QFN: 99 mm2: 9 x 11(B1QFN)    43B3QFN: 100 mm2: 10 x 10(B3QFN)   
1200    1000    1000    1000   
200    200    300    200   
400    500    400    500   
Synchronous Buck   
Synchronous Buck   
Buck    Buck
Synchronous Buck   
-40 to 105    -40 to 105    -40 to 85    -40 to 105   
18B2QFN    43B3QFN    41B1QFN    43B3QFN   
New! Interactive Design
Click to instantly view a schematic, charts, Bill of Materials, and Operating Values.

WEBENCH® Designer LMZM33603

  Min   Max Range
Vin  V 4.0 to 36.0V
Vout  V 1 to 18V
Iout  A ≤ 3A
Ambient Temp  °C -40 to 105°C

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