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1.8V to 28V Input, PWM Step-Up Controllers in µMAX

Flexible Converters Offer Step-Up, SEPIC, Flyback and Isolated Topologies. MAX668 Output Voltages Limited Only by External Component Ratings.

Product Details

Key Features

Parametric specs for Step-Up Switching Regulators
VIN (V) (min) 3
VIN (V) (max) 28
VOUT1 (V) (min) 3
VOUT1 (V) (max) 100
IOUT1 (A) (max) 6
Switch Type External
Output Adjust. Method Resistor
IQ (mA) (typ) 0.22
Shutdown Mode Supply Current (µA) (typ) 3.5
Shutdown Mode Supply Current (µA) (max) 6
# DC-DC Outputs 1
Switching Frequency (kHz) 500
Package/Pins UMAX/10
Budgetary
Price (See Notes)
2.78
View Less

Simplified Block Diagram

Technical Docs

Data Sheet 1.8V to 28V Input, PWM Step-Up Controllers in µMAX Jun 28, 2016
App Note Step-up Converter with LDO Beats SEPIC Efficiency
App Note Extending Soft-Start
App Note +12V Input Converter Generates -165V at 100mA
App Note 5V Input Converter Generates -30V at 80mA
App Note Simple Circuit Charges Lead-Acid Batteries
App Note Negative-to-Negative Switch-Mode Converter Offers High Current and High Efficiency
User Guide EE-SIM Design and Simulation Environment User Guide
App Note Current-Sense Amplifier Doubles as a High-Common Mode Instrumentation Amplifier
User Guide EE-SIM Design and Simulation Environment User Guide
App Note 15V Input Converter Generates -185V at 50mA
App Note ±15V or ±12V Output Switch-Mode Power Supply Has Wide Input-Voltage Range
App Note 3.3V Supply Taps Power from the -12V PCI Bus
App Note Dual-Output SLIC Supply Shares Feedback
App Note Current Limited DC-DC Controller Used as Step-Up Step-Down SEPIC Power Supply for USB Devices
App Note Isolated SLIC supply
App Note Step-Up Controller Forms Negative Step-Down Regulator
App Note High-Efficiency Boost Converter Provides 48V for IP Phones
App Note High-Efficiency Boost Converter Provides 24V for DTE
App Note R-C Snubbing for the Lab
App Note SLIC Power-Supply Design
Tutorial Reduce the Chances of Human Error: Part 1, Power and Ground
Tutorial Small, High-Voltage Boost Converters Guide | Maxim Integrated
Tutorial Layout Considerations for Non-Isolated DC-DC Converters
Tutorial Proper Layout and Component Selection Controls EMI
Tutorial DC to DC Buck Converter Tutorial & Diagram | Maxim Integrated

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 .

Sampling:
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Parameters

Parametric specs for Step-Up Switching Regulators
VIN (V) (min) 3
VIN (V) (max) 28
VOUT1 (V) (min) 3
VOUT1 (V) (max) 100
IOUT1 (A) (max) 6
Switch Type External
Output Adjust. Method Resistor
IQ (mA) (typ) 0.22
Shutdown Mode Supply Current (µA) (typ) 3.5
Shutdown Mode Supply Current (µA) (max) 6
# DC-DC Outputs 1
Switching Frequency (kHz) 500
Package/Pins UMAX/10
Budgetary
Price (See Notes)
2.78

Key Features

  • 1.8V Minimum Start-Up Voltage (MAX669)
  • Wide Input Voltage Range (1.8V to 28V)
  • Tiny 10-Pin µMAX Package
  • Current-Mode PWM and Idle Mode Operation
  • Efficiency Over 90%
  • Adjustable 100kHz to 500kHz Oscillator or SYNC Input
  • 220µA Quiescent Current
  • Logic-Level Shutdown
  • Soft-Start

Applications/Uses

  • Cellular Telephones
  • LANs and Network Systems
  • POS Systems
  • Telecom Hardware

Description

The MAX668/MAX669 constant-frequency, pulse-width modulating (PWM), current-mode DC-DC controllers are designed for a wide range of DC-DC conversion applications including step-up, SEPIC, flyback, and isolated-output configurations. Power levels of 20W or more can be controlled with conversion efficiencies of over 90%. The 1.8V to 28V input voltage range supports a wide range of battery and AC-powered inputs. An advanced BiCMOS design features low operating current (220µA), adjustable operating frequency (100kHz to 500kHz), soft-start, and a SYNC input allowing the MAX668/MAX669 oscillator to be locked to an external clock.

DC-DC conversion efficiency is optimized with a low 100mV current-sense voltage as well as with Maxim's proprietary Idle Mode™ control scheme. The controller operates in PWM mode at medium and heavy loads for lowest noise and optimum efficiency, then pulses only as needed (with reduced inductor current) to reduce operating current and maximize efficiency under light loads. A logic-level shutdown input is also included, reducing supply current to 3.5µA.

The MAX669, optimized for low input voltages with a guaranteed start-up voltage of 1.8V, requires boot-strapped operation (IC powered from boosted output). It supports output voltages up to 28V. The MAX668 operates with inputs as low as 3V and can be connected in either a bootstrapped or non-bootstrapped (IC powered from input supply or other source) configuration. When not bootstrapped, it has no restriction on output voltage. Both ICs are available in an extremely compact 10-pin µMAX® package.

Mobile App

Simplified Block Diagram

MAX668, MAX669: Typical Operating Circuit MAX668, MAX669: Typical Operating Circuit Zoom icon

Technical Docs

Data Sheet 1.8V to 28V Input, PWM Step-Up Controllers in µMAX Jun 28, 2016
App Note Step-up Converter with LDO Beats SEPIC Efficiency
App Note Extending Soft-Start
App Note +12V Input Converter Generates -165V at 100mA
App Note 5V Input Converter Generates -30V at 80mA
App Note Simple Circuit Charges Lead-Acid Batteries
App Note Negative-to-Negative Switch-Mode Converter Offers High Current and High Efficiency
User Guide EE-SIM Design and Simulation Environment User Guide
App Note Current-Sense Amplifier Doubles as a High-Common Mode Instrumentation Amplifier
User Guide EE-SIM Design and Simulation Environment User Guide
App Note 15V Input Converter Generates -185V at 50mA
App Note ±15V or ±12V Output Switch-Mode Power Supply Has Wide Input-Voltage Range
App Note 3.3V Supply Taps Power from the -12V PCI Bus
App Note Dual-Output SLIC Supply Shares Feedback
App Note Current Limited DC-DC Controller Used as Step-Up Step-Down SEPIC Power Supply for USB Devices
App Note Isolated SLIC supply
App Note Step-Up Controller Forms Negative Step-Down Regulator
App Note High-Efficiency Boost Converter Provides 48V for IP Phones
App Note High-Efficiency Boost Converter Provides 24V for DTE
App Note R-C Snubbing for the Lab
App Note SLIC Power-Supply Design
Tutorial Reduce the Chances of Human Error: Part 1, Power and Ground
Tutorial Small, High-Voltage Boost Converters Guide | Maxim Integrated
Tutorial Layout Considerations for Non-Isolated DC-DC Converters
Tutorial Proper Layout and Component Selection Controls EMI
Tutorial DC to DC Buck Converter Tutorial & Diagram | Maxim Integrated

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 .

Sampling:
Selecting the Sample button above will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.