MAXIM Integrated Products, represented by Arrow , has introduced the MAX5065 and MAX5067 dual-phase parallelable PWM controllers that enable design of high output current, compact power supplies with few external components.
These devices include an internal voltage regulator which allows operation from a 5V, 12V, or 24V power bus. The output voltage is externally adjustable from 0.6V to 3.3V for the MAX5065, and 0.8V to 3.3V for the MAX5067.
The MAX5065 and MAX5067's integrated 4A MOSFET drivers and high dissipation power allow up to 60A of output current. Multiple dc-dc controller modules can be paralleled to achieve higher output currents in units of 60A per module.
These devices have been designed to limit the reverse current if the bus voltage is higher than the programmed output voltage. The average-current-mode control enables ±5% current limit and current-sharing accuracy. This results in small inductors and small (or fewer) external MOSFETs, thus reducing power-supply size and cost.
The ±5% current-sharing accuracy is maintained between the phases and paralleled modules. In addition, 180° out-of-phase operation lowers the number of input capacitors required, minimising power-supply size and cost. The ±5% accurate internal-oscillator frequency is pin selectable at 250kHz or 500kHz per phase, resulting in a 500kHz or 1MHz effective switching frequency at the output.
The MAX5065 and MAX5067's output-feedback reference voltage is guaranteed at +0.8% over the -40°C to +85°C operating temperature range.
An active-adaptive voltage-positioning circuit provides good load transient response and also maximises efficiency by reducing power loss in the high-current PCB traces. When operating at high currents, these devices demonstrated up to 93% efficiency.
Other controller features include external-frequency synchronisation, phase-shifted clock output, true differential remote-output voltage sensing, and thermal shutdown. The MAX5067 also provides overvoltage protection, a power-good output, and a phase-failure detector output flag.
The MAX5065 is available in a surface-mount, 28-pin SSOP package, and the MAX5067 is available in a thermally enhanced, 44-pin QFN package. For a similar product with an Intel VRM9.0/VRM 9.1-compliant, five bit VID programmable output, refer to the MAX5037A.