November 1, 2013 – Linear Technology Korea (CEO Hong Sa-gwak) announced the launch of the LTM4633, a triple-output 10A step-down µModule® (micromodule) regulator in a 15 x 15 x 5.01mm BGA package with integrated heat sink for improved thermal dissipation. The LTM4633 integrates bypass capacitors and three resistors, fitting in less than 4.5cm² on a two-sided PCB. The LTM4633's high-integration heat sink is a technical feature previously introduced in the dual 13A LTM4620A, allowing each of the three outputs to deliver 10A from a 12VIN input to 1.8VOUT output at 88% efficiency at 52°C ambient temperature without external heat sink or air flow. When using an external heat sink and 200LFM air flow, the operating ambient temperature improves to 67°C. The LTM4633 provides DC/DC controller, power switches, inductor, and compensation circuitry in a single package. The regulated output voltage can be adjusted from 0.8V to 1.8V on two channels and from 0.8V to 5.5V on three channels, providing ±1.5% accuracy over line, load, and temperature.

The LTM4633's three switches have individual input power pins and operate with input voltages between 4.7V and 16V. With an additional external bias supply of 4.5V or higher, the minimum operating input voltage is reduced to 2.375V. The three switches operating from the same internal or selectable external clock signal are internally phase-shifted by 120° to minimize input ripple. For loads exceeding 10A, channels 1 and 2 can be paralleled to support up to 20A. Output overvoltage and overcurrent error protection are included in the regulator. The LTM4633's internal temperature can be monitored through two internal temperature diode monitors located next to the power stage.

The LTM4633 is available with guaranteed performance over internal temperature ranges of -40°C to +125°C or -55°C to +125°C. The µModule regulator is available immediately, priced at $35.95 per unit in quantities of 1,000. Detailed information is available at www.linear.com/product/LTM4633.