What this buck controller does on the board
The MAX1745AUB+: It drives an external transistor switch — no synchronous rectifier on-chip — so the bill of materials includes a Schottky catch diode and a low-side MOSFET or diode for the freewheeling path. Switching frequency runs up to 330 kHz, which is a middle ground: fast enough to keep the inductor small, but not so high that layout parasitics dominate the noise budget.
Package, temperature range, and where it fits
Housed in a 10-lead TFSOP/MSOP (3.00 mm wide) package, the MAX1745AUB+ is a surface-mount part for compact boards — the 10-uMAX/uSOP footprint is common in space-constrained power sections. Control features include an Enable pin and 100% duty cycle capability — the latter means the output can ride through brief input dips by keeping the high-side switch on continuously.
Lifecycle and compliance
ROHS3 compliant, which covers the full RoHS substance restriction list including the four phthalates.