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MAXIM New Products - MAX16993 & MAX16813
2013-07-22
MAX16993

Step-Down Controller with Dual 2.1MHz Step-Down DC-DC Converters

Highly Integrated Automotive PMIC with Three DC-DC Step-Down Outputs, Low IQ, and Low Minimum On-Time

Description

The MAX16993 power-management integrated circuit (PMIC) is a 2.1MHz, multichannel, DC-DC converter designed for automotive applications. The device integrates three supplies in a small footprint. The device includes one high-voltage step-down controller (OUT1) designed to run directly from a car battery and two low-voltage step-down converters (OUT2/OUT3) cascaded from OUT1. Under no-load conditions, the MAX16993 consumes only 30µA of quiescent current, making it ideal for automotive applications.
The high-voltage synchronous step-down DC-DC controller (OUT1) operates from a voltage up to 36V continuous and is protected from load-dump transients up to 42V. There is a pin-selectable frequency option of either 2.1MHz or a factory-set frequency for 1.05MHz, 525kHz, 420kHz, or 350kHz. The low-voltage, synchronous step-down DC-DC converters run directly from OUT1 and can supply output currents up to 3A.
The device provides a spread-spectrum enable input (SSEN) to provide quick improvement in electromagnetic interference when needed. There is also a SYNC I/O for providing either an input to synchronize to an external clock source or an output of the internally generated clock (see the Selector Guide in the full data sheet). The device includes overtemperature shutdown and overcurrent limiting. The device also includes individual active-low RESET_ outputs and individual enable inputs. The active-low RESET_ outputs provide voltage monitoring for all output channels.
The MAX16993 is available in a 32-pin side-wettable TQFN-EP package and is specified for operation over the -40°C to +125°C automotive temperature range.

Key Features

  • High-Voltage DC-DC Controller
    • 3.5V to 36V Operating Supply Voltage
    • 42V Load-Dump Protection
    • Output Voltage: Pin Selectable, Fixed or Resistor-Divider Adjustable
    • 350kHz to 2.1MHz Operation
    • 30µA Quiescent Current with DC-DC Controller Enabled
  • Dual High-Efficiency 2.1MHz DC-DC Converters
    • Run Directly from OUT1
    • 3A Integrated FETs
    • 0.8V to 3.95V Output Voltage
    • Fixed or Resistor-Divider-Adjustable Output Voltage
    • 180° Out-of-Phase Operation
  • Individual Enable Inputs
  • Individual Active-Low RESET_ Outputs
  • Thermal-Warning Indication Output
  • Forced-PWM and Skip Modes
  • Overtemperature and Short-Circuit Protection
  • 32-Pin (5mm × 5mm × 0.8mm) Side-Wettable TQFN-EP
  • -40°C to +125°C Operating Temperature Range
 
MAX16813

Integrated, 4-Channel, High-Brightness LED Driver with High-Voltage DC-DC Controller and Battery Disconnect

Multistring Driver Provides Highest Efficiency and Complete Fault Protection with the Lowest External Component Count

Description

The MAX16813 high-efficiency, high-brightness LED (HB LED) driver provides four integrated LED current-sink channels. An integrated current-mode switching controller drives a DC-DC converter that provides the necessary voltage to multiple strings of HB LEDs. The device accepts a wide 4.75V to 40V input voltage range and withstands direct automotive load-dump events. The wide input range allows powering HB LEDs for small- to medium-sized LCD displays in automotive and general lighting applications.
An internal current-mode switching DC-DC controller supports boost or SEPIC topologies and operates in an adjustable frequency range between 200kHz and 2MHz. An integrated spread-spectrum mode helps reduce EMI. Current-mode control with programmable slope compensation provides fast response and simplifies loop compensation. An adaptive output-voltage control scheme minimizes power dissipation in the LED current-sink paths. The device has a separate p-channel drive (PGATE) pin that is used for output undervoltage protection. Whenever the output falls below the threshold, the external p-MOSFET is latched off, disconnecting the input source. Cycling the EN or the input supply is required to restart the converter. The external p-MOSFET is off when the EN pin is below 0.3V (typ). The shutdown current is 1µA (typ) at an input voltage of 12V.
The device consists of four identical linear current-sink channels, adjustable from 20mA to 150mA with an accuracy of ±3% using a single external resistor. Multiple channels can be connected in parallel to achieve higher current per LED string. The device also features a unique pulsed dimming control through a logic input (DIM), with minimum pulse width as low as 500ns. Protection features include output overvoltage, open-LED detection and protection, programmable shorted LED detection and protection, output undervoltage protection and detection, and overtemperature protection. The device operates over the -40°C to +125°C automotive temperature range. The MAX16813 is available in 20-pin (6.5mm x 4.4mm) TSSOP and 20-pin (4mm x 4mm) TQFN packages.

Key Features

  • 4-Channel Linear LED Current Sinks with Internal MOSFETs
    • Full-Scale LED Current Adjustable from 20mA to 150mA
    • Drives 1 to 4 LED Strings
  • Boost or SEPIC Current-Mode DC-DC Controller
    • 200kHz to 2MHz Programmable Switching Frequency
    • External Switching Frequency Synchronization
    • Spread-Spectrum Mode to Reduce EMI
  • Adaptive Output-Voltage Optimization to Minimize Power Dissipation
  • Output-to-Ground Undervoltage Protection
  • 4.75V to 40V Operating Input Voltage Range
  • Less than 2µA Shutdown Current
  • 10000:1 PWM Dimming at 200Hz
  • Open-Drain Fault-Indicator Output
  • Open-LED and LED Short Detection and Protection
  • Overtemperature Protection
  • Thermally Enhanced, 20-Pin TQFN and TSSOP Packages

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