MAX1744/MAX1745 are high-voltage, step-down DC-DC controllers capable of handling up to 36V inputs. These parts use a proprietary current-limited control scheme for excellent light- and full-load efficiency, while their 330kHz (max) switching frequency permits small external components for space-critical applications.
The MAX1744 and MAX1745 are step‑down DC‑DC controller devices that operate from 4.5 V to 36 V input and provide selectable fixed 3.3 V or 5 V outputs (MAX1744) or an adjustable 1.25 V‑to‑18 V output (MAX1745). They are offered in a compact 10‑pin UMAX package and are targeted at automotive electronics, telecom systems, wall‑cube‑powered devices, industrial control and FireWire/IEEE‑1394 applications.
Key features include high‑voltage operation up to 36 V, efficiency greater than 90 %, output power capability exceeding 50 W, a 330 kHz maximum switching frequency, 90 µA quiescent current and 4 µA shutdown current. The devices use a current‑limited control scheme and can operate at 100 % duty cycle for ultra‑low dropout performance. Detailed pin descriptions, electrical characteristics, typical operating curves and package dimensions are provided.
| Input Voltage Range | 4.5 V to 36 V |
|---|---|
| Efficiency | > 90 % |
| Output Power Capability | Exceeds 50 W |
| Maximum Switching Frequency | 330 kHz (max) |
| Quiescent Current | 90 µA |
| Shutdown Current | 4 µA |
The device operates from 4.5 V up to 36 V input.
The MAX1744 provides a selectable fixed output of either 3.3 V or 5 V.
Both devices can deliver more than 50 W of output power.
The quiescent current is 90 µA.