MAX5033 High-Efficiency, High-Voltage, Step-Down DC-DC Converter

The MAX5033 is an easy-to-use, high-efficiency, high-voltage, step-down DC-DC converter that operates from input voltages up to 76V and consumes only 270µA of quiescent current at no load. The pulse-width modulated (PWM) converter operates at a fixed 125kHz switching frequency when heavily loaded and automatically switches to pulse-skipping mode when lightly loaded to achieve low quiescent current and high efficiency. The MAX5033 includes internal frequency compensation to simplify circuit implementation. Low on-resistance, high-voltage DMOS transistors are used internally to achieve high efficiency and reduce overall system cost. The device includes undervoltage lockout, cycle-by-cycle current limit, burst-mode output short-circuit protection, and thermal shutdown.

The MAX5033 provides up to 500mA of output current. An external shutdown mode is provided with 10µA (typ) shutdown current. The MAX5033A/B/C models provide fixed output voltages of 3.3V, 5V, or 12V, respectively; the MAX5033D provides an adjustable output voltage from 1.25V to 13.2V.

The MAX5033 is available in a space-saving 8-pin SO or 8-pin plastic DIP package and operates over the automotive (-40°C to +125°C) temperature range.

Key Features

Wide 7.5V to 76V Input Voltage Range

Provides fixed (3.3V, 5V, 12V) and adjustable voltage (1.25V to 13.2V)

500mA output current

Efficiency up to 94%

Built-in 0.4Ω high-side DMOS FET

270µA quiescent current at no load; 10µA shutdown current

Internal frequency compensation

Fixed 125kHz switching frequency

Thermal Shutdown and Short Circuit Current Limiting

8-pin SO and PDIP packages

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