MAX17244 Datasheet, PDF (1/18 Pages) Maxim Integrated Products – Eliminates External Components and Reduces

MAX17244
EVALUATION KIT AVAILABLE
3.5V–36V, 2.5A, Synchronous Buck Converter
With 28µA Quiescent Current and Reduced EMI
General Description
The MAX17244 high-efficiency, synchronous step-down
DC-DC converter with integrated MOSFETs operates
over a 3.5V to 36V input voltage range with 42V input
transient protection. The device can operate in dropout
condition by running at 98% duty cycle. This converter
delivers up to 2.5A and generates fixed output voltages of
3.3V/5V, along with the ability to program the output
voltage between 1V to 10V.
The MAX17244 uses a current-mode control architecture.
The device can operate in the pulse-width modulation
(PWM) or pulse-frequency modulation (PFM) control
schemes. PWM operation provides constant frequency
operation at all loads, and is useful in applications sensitive
to switching frequency. PFM operation disables negative
inductor current and additionally skips pulses at light
loads for high efficiency. Under light-load applications,
the external sync pin FSYNC logic input allows the
device to operate either in PFM mode for reduced current
consumption or fixed-frequency FPWM (forced-PWM)
mode to eliminate frequency variation to minimize EMI.
Fixed-frequency FPWM mode is extremely useful for
power supplies designed for RF transceivers where tight
emission control is necessary.
This device is available in a compact 16-pin (5mm x 5mm)
TQFN package with exposed pad and 16-pin TSSOP.
-40°C to +85°C operation.
Applications
●● Distributed Supply Regulation
●● Wall Transformer Regulation
●● General-Purpose Point-of-Load
Benefits and Features
●● Eliminates External Components and Reduces
Total Cost
• Integrated High-Side and Low-Side Switch Enables
Synchronous Operation for High Efficiency and
Reduced Cost
• All-Ceramic Capacitor Solution Allows Ultra-
Compact Solution Size
• 220kHz to 2.2MHz Adjustable Frequency with
External Synchronization
• Power Good Output and High-Voltage EN Input
Simplify Power Sequencing
●● Increases Design Flexibility
• 180° Out-of-Phase Clock Output at SYNCOUT
Enables Cascaded Power Supplies for Increased
Power Output
• Fixed Output Voltage with ±2% Accuracy (5V/3.3V)
or Externally Resistor Adjustable (1V to 10V)
●● Reduces Power Dissipation
• >90% Peak Efficiency
• PWM and PFM Operation Optimizes Conversion
Efficiency From Heavy to Light Loads
• Automatic LX Slew-Rate Adjustment for Optimum
Efficiency Across Operating Frequency Range
• Low 5μA (typ.) Shutdown Current
• Low 28μA (typ.) Quiescent Current
●● Operates Reliably
• 42V Input Voltage Transient Protection
• Fixed 8ms Internal Software Start Reduces Input
Inrush Current
• Cycle-by-Cycle Current Limit, Thermal Shutdown
with Automatic Recovery
• Reduced EMI Emission with Spread-Spectrum
Control
Ordering Information and Typical Application Circuit
appears at end of data sheet.
19-8526; Rev 0; 4/16