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LM317DCYR

LM317DCYR

Various
Classic adjustable linear regulator available from multiple manufacturers, suitable for many general-purpose applications.
NRND65,965 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The LM317DCYR is a versatile, adjustable three-terminal positive voltage regulator capable of supplying up to 1.5A over an output range of 1.25V to 37V. It is a industry-standard linear regulator that requires only two external resistors to set the output voltage, providing internal current limiting, thermal shutdown, and safe-area compensation.

Why Choose This Part

The SOT-223 package offers a compact footprint for surface-mount designs while maintaining high current capability up to 1.5A. It features robust protection including thermal overload and short-circuit current limiting, and provides high ripple rejection of up to 80dB at 120Hz.

Applications

Adjustable Power Supplies
Primary regulation stage for variable laboratory or system-level power supplies where a custom output voltage is required.
Local On-Card Regulation
Providing stable power to specific subsystems from a higher-voltage unregulated rail within a single PCB design.
Current Limiters
Configured as a precision current source to protect sensitive downstream loads or drive high-brightness LEDs.
Battery Chargers
Utilized in constant-current or constant-voltage charging circuits for various battery chemistries.

Key Specifications

PSRR 64dB ~ 57dB (120Hz)
Output Type Adjustable
Mounting Type Surface Mount
Package / Case TO-261-4, TO-261AA
Current - Output 1.5A
Protection Features Over Current, Over Temperature, Short Circuit
Number of Regulators 1
Output Configuration Positive
Operating Temperature 0degC ~ 125degC
Voltage - Input (Max) 40V
Voltage - Output (Max) 37V
Supplier Device Package SOT-223-4
Current - Quiescent (Iq) 10 mA
Voltage - Output (Min/Fixed) 1.25V

Getting Started

To implement the LM317DCYR, select two external resistors (R1 and R2) to set the output voltage using the standard Vout = 1.25V * (1 + R2/R1) formula. Ensure adequate thermal relief on the SOT-223 tab and place a 0.1uF input capacitor and a 1uF output capacitor to improve transient response and stability.

Part of LM317 family » LM317

LM317 Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number PSRR Package Output I Current - Quiescent (Iq) Output V Stock
LM317DCYR (this part) 120Hz 4-261 1.5A 10 mA 1.25V 65,965
LM317LZ 120Hz 3-226 100mA 5 mA 1.2V 21,947
Also available as: LM317MDT-TR

Also Consider

LM317AT TITexas Instruments - Available in a TO-220 through-hole package for higher power dissipation and easier breadboarding.

Categories

Power Management > LDO Voltage Regulators