Top

High-Speed Step-Down Controller for Notebook Computers

Low-Cost, Ultra-Fast, 1%-Accurate Controllers Power Next-Generation Notebook CPU Core and I/O

Product Details

The MAX1714 pulse-width modulation (PWM) controller provides the high efficiency, excellent transient response, and high DC output accuracy needed for stepping down high-voltage batteries to generate low-voltage CPU core or chip-set/RAM supplies in notebook computers.

Maxim's proprietary Quick-PWM™ quick-response, constant-on-time PWM control scheme handles wide input/output voltage ratios with ease and provides 100ns "instant-on" response to load transients while maintaining a relatively constant switching frequency.

The MAX1714 achieves high efficiency at a reduced cost by eliminating the current-sense resistor found in traditional current-mode PWMs. Efficiency is further enhanced by an ability to drive very large synchronous-rectifier MOSFETs.

Single-stage buck conversion allows these devices to directly step down high-voltage batteries for the highest possible efficiency. Alternatively, two-stage conversion (stepping down the +5V system supply instead of the battery) at a higher switching frequency allows the minimum possible physical size.

The MAX1714 is intended for CPU core, chipset, DRAM, or other low-voltage supplies as low as 1V. The MAX1714A is available in a 20-pin QSOP package and includes overvoltage protection. The MAX1714B is available in a 16-pin QSOP package with no overvoltage protection. For applications requiring VID compliance or DAC control of output voltage, refer to the MAX1710/MAX1711 data sheet. For a dual output version, refer to the MAX1715 data sheet.

Key Features

  • Ultra-High Efficiency
  • No Current-Sense Resistor (Lossless ILIMIT)
  • Quick-PWM with 100ns Load-Step Response
  • 1% VOUT Accuracy Over Line and Load
  • 2.5V/3.3V Fixed or 1V to 5.5V Adjustable Output Range
  • 2V to 28V Battery Input Range
  • 200/300/450/600kHz Switching Frequency
  • Overvoltage Protection (MAX1714A)
  • Undervoltage Protection
  • 1.7ms Digital Soft-Start
  • Drives Large Synchronous-Rectifier FETs
  • 2V ±1% Reference Output
  • Power-Good Indicator

Applications/Uses

  • 1.8V and 2.5V I/O Supplies
  • Chipset/RAM Supplies as Low as 1V
  • CPU Core Supplies
  • Notebook Computers
Parametric specs for Step-Down (Buck) Switching Regulators
VIN (V) (min) 2
VIN (V) (max) 28
VOUT1 (V) (min) 1
VOUT1 (V) (max) 5.5
IOUT1 (A) (max) 8
Switch Type External
Preset VOUT (V) 2.5
3.3
Output Adjust. Method Preset
Resistor
Synchronous Switching Yes
# DC-DC Outputs 1
Switching Frequency (kHz) 600
Package/Pins SOIC(N)/8
Budgetary
Price (See Notes)
$3.06 @1k
View More

Simplified Block Diagram

MAX1714, MAX1714A, MAX1714B: Minimal Operating Circuit MAX1714, MAX1714A, MAX1714B: Minimal Operating Circuit Zoom icon

Technical Docs

Design & Development

Click any title below to view the detail page where available.

Description

The MAX1714A evaluation kit (EV kit) demonstrates a standard 4A application circuit. This DC-DC converter steps down high-voltage batteries and/or AC adapters, generating a precision, low-voltage rail for use as chipset, DRAM, and other low-voltage supplies. For higher current applications up to 12A, refer to the MAX1714A data sheet.

The MAX1714A EV kit provides a 2.5V output voltage from a +5V to +24V battery input range. It delivers up to 4A output current with greater than 90% efficiency while operating at a 300kHz switching frequency, and has superior line- and load-transient response.

This EV kit is a fully assembled and tested circuit board. It also allows evaluation of other output voltages in the 1.0V to 5.5V range by changing feedback resistors R1 and R2.

View Details

Features

  • +5V to +24V Input Voltage Range
  • Preset 2.5V Output Voltage
  • 1.0V to 5.5V Adjustable Output
  • 4A Output Current
  • 94% Efficient (VOUT = 2.5V, VBATT = 7V, ILOAD = 2A)
  • 300kHz Switching Frequency
  • No Current-Sense Resistor
  • Power-Good Output
  • Low-Profile Components
  • Fully Assembled and Tested

Description

The MAX1714B evaluation kit (EV kit) demonstrates a standard 4A application circuit. This DC-DC converter steps down high-voltage batteries and/or AC adapters, generating a precision, low-voltage rail for use as chipset, dynamic random-access memory (DRAM), and other low-voltage supplies.

The MAX1714B EV kit provides a 2.5V output voltage from a +4.5V to +24V battery input range. It delivers up to 4A output current with greater than 90% efficiency while operating at a 300kHz switching frequency, and has superior line- and load-transient response.

This EV kit is a fully assembled and tested circuit board. It also allows evaluation of other output voltages in the 1.0V to 5.5V range by changing feedback resistors R1 and R2.

View Details

Features

  • +4.5V to +24V Input Voltage Range
  • Preset 2.5V Output Voltage
  • 1.0V to 5.5V Adjustable Output
  • 4A Output Current
  • 94% Efficient (VOUT = 2.5V, VBATT = 7V, ILOAD = 2A)
  • 300kHz Switching Frequency
  • No Current-Sense Resistor
  • Power-Good Output
  • 16-Pin QSOP Package
  • Low-Profile Components
  • Fully Assembled and Tested

/en/design/design-tools/ee-sim.html?

Support & Training

Search our knowledge base for answers to your technical questions.

Filtered Search

Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal.

Parameters

Parametric specs for Step-Down (Buck) Switching Regulators
VIN (V) (min) 2
VIN (V) (max) 28
VOUT1 (V) (min) 1
VOUT1 (V) (max) 5.5
IOUT1 (A) (max) 8
Switch Type External
Preset VOUT (V) 2.5
3.3
Output Adjust. Method Preset
Resistor
Synchronous Switching Yes
# DC-DC Outputs 1
Switching Frequency (kHz) 600
Package/Pins SOIC(N)/8
Budgetary
Price (See Notes)
$3.06 @1k

Key Features

  • Ultra-High Efficiency
  • No Current-Sense Resistor (Lossless ILIMIT)
  • Quick-PWM with 100ns Load-Step Response
  • 1% VOUT Accuracy Over Line and Load
  • 2.5V/3.3V Fixed or 1V to 5.5V Adjustable Output Range
  • 2V to 28V Battery Input Range
  • 200/300/450/600kHz Switching Frequency
  • Overvoltage Protection (MAX1714A)
  • Undervoltage Protection
  • 1.7ms Digital Soft-Start
  • Drives Large Synchronous-Rectifier FETs
  • 2V ±1% Reference Output
  • Power-Good Indicator

Applications/Uses

  • 1.8V and 2.5V I/O Supplies
  • Chipset/RAM Supplies as Low as 1V
  • CPU Core Supplies
  • Notebook Computers

Description

The MAX1714 pulse-width modulation (PWM) controller provides the high efficiency, excellent transient response, and high DC output accuracy needed for stepping down high-voltage batteries to generate low-voltage CPU core or chip-set/RAM supplies in notebook computers.

Maxim's proprietary Quick-PWM™ quick-response, constant-on-time PWM control scheme handles wide input/output voltage ratios with ease and provides 100ns "instant-on" response to load transients while maintaining a relatively constant switching frequency.

The MAX1714 achieves high efficiency at a reduced cost by eliminating the current-sense resistor found in traditional current-mode PWMs. Efficiency is further enhanced by an ability to drive very large synchronous-rectifier MOSFETs.

Single-stage buck conversion allows these devices to directly step down high-voltage batteries for the highest possible efficiency. Alternatively, two-stage conversion (stepping down the +5V system supply instead of the battery) at a higher switching frequency allows the minimum possible physical size.

The MAX1714 is intended for CPU core, chipset, DRAM, or other low-voltage supplies as low as 1V. The MAX1714A is available in a 20-pin QSOP package and includes overvoltage protection. The MAX1714B is available in a 16-pin QSOP package with no overvoltage protection. For applications requiring VID compliance or DAC control of output voltage, refer to the MAX1710/MAX1711 data sheet. For a dual output version, refer to the MAX1715 data sheet.

Simplified Block Diagram

MAX1714, MAX1714A, MAX1714B: Minimal Operating Circuit MAX1714, MAX1714A, MAX1714B: Minimal Operating Circuit Zoom icon

Technical Docs

Support & Training

Search our knowledge base for answers to your technical questions.

Filtered Search

Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal.