DC-DC Controller Connects Multiple Power Modules

The TPS40180 synchronous dc-dc controller from Texas Instruments lets system designers connect multiple power modules, resulting in a high-density power supply that supports a 10- to 200-A output. Based on the TPS40140 dual-phase controller, the single-channel version provides greater design flexibility when additional circuitry or daughtercards are added to the board. A load-share feature enables modular power-supply design so modules can be paralleled together, with each delivering power equally to the load. The controller's automatic phase-balancing feature minimizes the ripple current in both the output and input capacitors, reducing the supply's overall size. Designers can also implement topologies in which multiple output rails can be synchronized to achieve higher power density and more flexibility while minimizing electromagnetic interference.

The device supports a wide input-voltage conversion range of 2 to 40 V and operates from a 4.5- to 15-V power source. It converts from 15-V input to 0.7-V output at a programmable switching frequency of 1-MHz per phase, resulting in an effective ripple frequency of up to 8 MHz at the input and output during operation. The TPS40180 also has excellent line and load regulation of 0.1%, supported by a ±0.5%, 0.7-V reference and a high-accuracy differential load sense amplifier. The controller incorporates complete supervisory and control features, including pre-bias startup capability, programmable undervoltage lockout, lossless dc resistance or resistor current sensing, power good, soft-start control, synchronization input, programmable overcurrent protection, and thermal shutdown. It comes in a 4- by 4-mm, 24-pin quad flat no-lead (QFN) package.