MAX17551 Datasheet, PDF (1/20 Pages) Maxim Integrated Products – Synchronous Step-Down DC-DC Converter

MAX17551
60V, 50mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
with 22µA No-Load Supply Current
General Description
The MAX17551 high-efficiency, high-voltage, syn-
chronous step-down DC-DC converter with integrated
MOSFETs operates over a 4V to 60V input. The converter
can deliver up to 50mA and generates output voltages
from 0.8V up to 0.9 x V_IN. The feedback (FB) voltage is
accurate to within ±1.75% over -40°C to +125°C.
The MAX17551 uses peak-current-mode control and can
be operated in pulse-width modulation (PWM) or pulse-
frequency modulation (PFM) modes.
The device is available in a 10-pin (3mm x 2mm) TDFN
and 10-pin (3mm x 3mm) μMAX® packages. Simulation
models are available.
Applications
●● Industrial Sensors and Process Control
●● High-Voltage LDO Replacement
●● Battery-Powered Equipment
●● HVAC and Building Control
µMAX is a registered trademark of Maxim Integrated Products, Inc.
Ordering Information appears at end of data sheet.
Features and Benefits
●● Reduces External Components and Total Cost
• No Schottky–Synchronous
• Internal Compensation for Any Output Voltage
• Built-In Soft-Start
• All-ceramic capacitors, Compact Layout
●● Reduces Number of DC-DC Regulators to Stock
• Wide 4V to 60V Input
• Adjustable 0.8V to 0.9 x V_IN Output
• 100kHz to 2.2MHz Adjustable Switching Frequency
with External Synchronization
●● Reduces Power Dissipation
• 22µA Quiescent Current
• Peak Efficiency > 90%
• PFM Enables Enhanced Light-load Efficiency
• 1.2µA Shutdown Current
●● Operates Reliable in Adverse Environments
• Peak Current Limit Protection
• Built-In Output Voltage Monitoring RESET
• Programmable EN/UVLO Threshold
• Monotonic Startup in to Prebiased Load
• Overtemperature Protection
• -40°C to +125°C Operation
Typical Application Circuit—High-Efficiency 5V, 50mA Regulator
V_IN
6V TO 60V
C_IN
1µF
R3
140kΩ
IN
LX
MAX17551
EN/UVLO
GND
SS
V_OUT
MODE
FB
RT/SYNC
RESET
L1
330µH
V_OUT
5V
C_OUT
10µF
R4
22.1Ω
C1
0.22µF
R1
261kΩ
R2
49.9kΩ
L1 COILCRAFT LPS5030-334M
C_OUT MURATA 10µF/X7R/6.3V/0805 (GRM21BR70J106K)
C_IN MURATA 1µF/X7R/100V/1206 (GRM31CR72A105K)
19-7110; Rev 0; 9/14