MAX1744/MAX1745 are high-voltage, step-down DC-DC controllers in µMAX 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. Operation to 100% duty cycle permits the lowest possible dropout voltage. The MAX1744 contains an internal feedback network that provides a pin-selectable output voltage of either 3.3V or 5V. The MAX1745 uses an external feedback network to generate an adjustable output voltage between 1.25V and 18V. The MAX1744/MAX1745 are available in a space-saving 10-pin µMAX package.
The MAX1744 and MAX1745 are high‑voltage step‑down DC‑DC controller ICs designed for automotive, telecom and other industrial‑control applications. They operate from 4.5 V to 36 V input and can deliver up to 50 W of output power while maintaining low quiescent current.
Key features include a proprietary current‑limited control scheme, up to 330 kHz switching frequency, 100 % duty‑cycle operation for low dropout, selectable 3.3 V or SV output (MAX1744) and an external feedback network for a 1.25 V‑18 V adjustable output (MAX1745). The devices are supplied in a 10‑pin UMAX package and are intended for space‑critical designs.
| Input Voltage Range | 4.5 V – 36 V |
|---|---|
| Supply Current (typical) | 140 µA |
| Shutdown Supply Current (typical) | 12 µA |
| Adjustable Output Voltage (MAX1745) | 1.25 V – 18 V |
| Efficiency | >90 % |
| Maximum Switching Frequency | 330 kHz |
| Quiescent Current | 90 µA |
| Shutdown Current | 4 µA |
| Package | 10‑pin UMAX |
The devices can operate with an input voltage up to 36 V.
Typical efficiency is greater than 90 %.
Both parts are supplied in a 10‑pin UMAX package.