Automotive High-Efficiency 2.2MHz, 36V, Dual Buck Controller with 17μA Quiescent Current

The MAX20034 is an automotive 2.2MHz, dual synchronous step-down controller IC that provides two high-voltage, synchronous step-down controllers that operate 180° out-of-phase. The IC operates with a 3.5V to 42V input-voltage supply and can function in dropout condition by running at 99% duty cycle. It is intended for applications with mid- to high-power requirements that perform at a wide input voltage range, such as during automotive cold-crank or engine stop-start conditions.

The IC’s step-down controllers operate at up to 2.2MHz frequency to allow small external components, reduced output ripple, and to guarantee no AM band interference. The switching frequency is resistor adjustable (220kHz to 2.2MHz). SYNC input programmability enables three frequency modes for optimized performance: forced fixed-frequency operation, skip mode with ultra-low-quiescent current, and synchronization to an external clock. The IC is also available with spread-spectrum frequency modulation to minimize EMI interference.

The IC features a power-OK monitor, overvoltage lockout, and undervoltage lockout. Protection features include cycle-by-cycle current limit and thermal shutdown. The MAX20034 is specified for operation over the -40°C to +125°C automotive temperature range.

Applications

* Distributed DC Power Systems * Navigation and Radio Head Units * POL Applications for Automotive Power

* Meets Stringent Automotive OEM Module Power-Consumption and Performance Specifications

* 17µA Quiescent Current in Skip Mode

* ±1.5% Output-Voltage Accuracy: 5.0V/3.3V Fixed, or Adjustable Between 1V and 10V

* Enables Crank-Ready Designs

* Wide 3.5V to 36V Input Supply Range

* EMI Reduction Features Reduce Interference with Sensitive Radio Bands without Sacrificing Wide Input Voltage Range

* 50ns (typ) Minimum On-Time Guarantees Skip-Free Operation for 3.3V Output from a Car Battery at 2.2MHz

* Spread-Spectrum Option

* Frequency-Synchronization Input

* Resistor-Programmable Frequency Between 220kHz and 2.2MHz

* Integration and Thermally Enhanced Packages Save Board Space and Cost

* Dual, Up to 2.2MHz Step-Down Controllers

* 180° Out-of-Phase Operation

* Current-Mode Controllers with Forced-PWM (FPWM) and Skip Modes

* Thermally Enhanced, 28-Pin TQFN-EP Package

* Protection Features Improve System Reliability

* Supply Overvoltage and Undervoltage Lockout

* Overtemperature and Short-Circuit Protection