MAX668
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.
Top
Overview
Features and Benefits
- 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
Product Details
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.
Applications
- Cellular Telephones
- LANs and Network Systems
- POS Systems
- Telecom Hardware
Product Categories
Product Lifecycle
Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Documentation & Resources
-
MAX668 Reliability Data1/12/2023PDF147K
-
UG-5861: EE-SIM Design and Simulation Environment User Guide5/5/2014PDF3M
-
Current-Sense Amplifier Doubles as a High-Common Mode Instrumentation Amplifier12/3/2012
-
Negative-to-Negative Switch-Mode Converter Offers High Current and High Efficiency2/2/2011
-
Current Limited DC-DC Controller Used as Step-Up Step-Down SEPIC Power Supply for USB Devices8/6/2002
-
Isolated SLIC supply6/14/2002
-
High-Efficiency Boost Converter Provides 24V for DTE12/27/2001
-
High-Efficiency Boost Converter Provides 48V for IP Phones12/27/2001
-
Simple Circuit Charges Lead-Acid Batteries6/1/2001
-
Step-up Converter with LDO Beats SEPIC Efficiency12/1/2000
-
5V Input Converter Generates -30V at 80mA11/1/2000
-
15V Input Converter Generates -185V at 50mA11/1/2000
-
Extending Soft-Start11/1/2000
-
+12V Input Converter Generates -165V at 100mA11/1/2000
-
Dual-Output SLIC Supply Shares Feedback8/7/2000
-
3.3V Supply Taps Power from the -12V PCI Bus2/7/2000
-
Reduce the Chances of Human Error: Part 1, Power and Ground3/8/2011
-
±15V or ±12V Output Switch-Mode Power Supply Has Wide Input-Voltage Range12/7/2006
-
Proper Layout and Component Selection Controls EMI8/21/2002
-
Small, High-Voltage Boost Converters7/4/2002
-
Step-Up Controller Forms Negative Step-Down Regulator1/31/2002
-
R-C Snubbing for the Lab12/27/2001
-
DC to DC Buck Converter Tutorial & Diagram11/29/2001
-
Layout Considerations for Non-Isolated DC-DC Converters11/29/2001
-
SLIC Power-Supply Design6/1/2001
Reference Designs (2)
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Support & Discussions
Sample & Buy
Ordering FAQs
See our Ordering FAQs for answers to questions about online orders, payment options and more.
Buy Now Pricing
(**) Displayed Buy Now Price and Price Range is based on small quantity orders.
List Pricing
(*)The 1Ku list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
Lead Times
Please see the latest communication from our CCO regarding lead times.
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.
Evaluation Boards
Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.