MAXREFDES1200: Two-Layer Board, 3.3V/2.5A, Synchronous Buck DC-DC Converter Using the MAX17244
|Input Type||VIN (MIN)
The MAXREFDES1200 demonstrates how to build a lowcost buck DC-DC converter using the step-down converter MAX17244 for 3.3V DC output applications from a 12V to 32V input. This reference design delivers up to 2.5A at 3.3V. This design uses a two-layer board and minimizes component count to reduce cost. An overview of the design specification is shown in table above.
The MAX17244 high-efficiency, synchronous step-down DC-DC converter with integrated MOSFETs operates over a 3.5V to 36V input voltage range with 42V input transient protection. It uses a current-mode control architecture and can operate in the pulse-width modulation (PWM) or pulse-frequency modulation (PFM) control schemes. The device can operate in dropout conditions by running at 98% duty cycle. Under light-load applications, the external sync pin FSYNC logic input allows the device to operate either in PFM mode for reduced current consumption or fixed-frequency FPWM (forced-PWM) mode to eliminate frequency variation to minimize EMI. This converter delivers up to 2.5A and generates fixed output voltages of 3.3V/5V, along with the ability to program the output voltage between 1V to 10V. This device is available in a compact 16-pin (5mm x 5mm) TQFN package with exposed pad and 16-pin TSSOP.
Designed, Built, Tested
This reference design describes the hardware shown above. It provides a detailed systematic technical guide to design a buck converter using Maxim’s MAX17244 step-down controller. The power supply has been built and tested, details of which follow later in this document.