The LTM4644IY#PBF is a high-performance Quad 4A (16A total) Step-Down µModule® (micromodule) Regulator manufactured by Analog Devices (originally developed by Linear Technology).

It is a "complete" power supply in a single package, containing the switching controllers, power FETs, inductors, and support components required for four independent voltage rails.

Key Technical Specifications

• Architecture: Quad output (4 independent channels).
• Input Voltage Range: 4V to 14V (can go as low as 2.375V with an external bias supply).
• Output Voltage Range: 0.6V to 5.5V (adjustable via resistors).
• Output Current: 4A per channel (continuous).
• Scalability: Channels can be paralleled to provide up to 16A on a single rail.
• Switching Frequency: 1 MHz (typical).[1][2][3][4]
• Package: 77-lead BGA (15mm × 9mm × 5.01mm).
• Operating Temperature: -40°C to +125°C (Industrial Grade).

Part Number Decoder

• LTM: Linear Technology Module (µModule family).
• 4644: The base model number for this quad-output regulator.[1][5][6]
• I: Industrial Temperature Grade (-40°C to +125°C).[1]
• Y: BGA Package (Ball Grid Array).
• #PBF: Lead-Free / RoHS Compliant.

Major Features

1. Configurable Output Array: You can use it as four separate 4A outputs, or combine them into configurations like 8A + 4A + 4A, 12A + 4A, or a single 16A output.
2. High Efficiency: Uses a current-mode control architecture for fast transient response and stable operation.
3. Protection: Includes overvoltage (OVP), overcurrent (OCP), and overtemperature (OTP) protection.
4. Ease of Use: Because the inductors and FETs are integrated, the PCB layout is much simpler and takes up significantly less space compared to discrete solutions.